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More Bad News for Radiometric Dating


Here I want to concentrate on another source of error, namely, processes that take place within magma chambers. To me it has been a real eye opener to see all the processes that are taking place and their potential influence on radiometric dating. Radiometric dating is largely done on rock that has formed from solidified lava. Lava (properly called magma before it erupts) fills large underground chambers called magma chambers. Most people are not aware of the many processes that take place in lava before it erupts and as it solidifies, processes that can have a tremendous influence on daughter to parent ratios. Such processes can cause the daughter product to be enriched relative to the parent, which would make the rock look older, or cause the parent to be enriched relative to the daughter, which would make the rock look younger. This calls the whole radiometric dating scheme into serious question.

Geologists assert that older dates are found deeper down in the geologic column, which they take as evidence that radiometric dating is giving true ages, since it is apparent that rocks that are deeper must be older. But even if it is true that older radiometric dates are found lower down in the geologic column, which is open to question, this can potentially be explained by processes occurring in magma chambers which cause the lava erupting earlier to appear older than the lava erupting later. Lava erupting earlier would come from the top of the magma chamber, and lava erupting later would come from lower down. A number of processes could cause the parent substance to be depleted at the top of the magma chamber, or the daughter product to be enriched, both of which would cause the lava erupting earlier to appear very old according to radiometric dating, and lava erupting later to appear younger.


Mechanisms that can alter daughter-to-parent ratios
What happens when magma solidifies and melts and its implications for radiometric dating
The following quote from The Earth: An Introduction to Physical Geology by Tarbuck & Lutgens, pp. 55-57, (1987), gives us an idea of the tremendous complexity of the processes that occur when magma solidifies. The general idea is that many different minerals are formed, which differ from one another in composition, even though they come from the same magma.
The mineral makeup of an igneous rock is ultimately determined by the chemical composition of the magma from which it crystallized. Such a large variety of igneous rocks exists that it is logical to assume an equally large variety of magmas must also exist. However, geologists have found that various eruptive stages of the same volcano often extrude lavas exhibiting somewhat different mineral compositions, particularly if an extensive period of time separated the eruptions. Evidence of this type led them to look into the possibility that a single magma might produce rocks of varying mineral content.

A pioneering investigation into the crystallization of magma was carried out by N. L. Bowen in the first quarter of this century. Bowen discovered that as magma cools in the laboratory, certain minerals crystallize first. At successively lower temperature, other minerals begin to crystallize as shown in Figure 3.6. As the crystallization process continues, the composition of the melt (liquid portion of a magma, excluding any solid material continually changes. For example, at the stage when about 50 percent of the magma has solidified, the melt will be greatly depleted in iron, magnesium, and calcium, because these elements are found in the earliest formed minerals. But at the same time, it will be enriched in the elements contained in the later forming minerals, namely sodium and potassium. Further, the silicon content of the melt becomes enriched toward the latter stages of crystallization. Bowen also demonstrated that if a mineral remained in the melt after it had crystallized, it would react with the remaining melt and produce the next mineral in the sequence shown in Figure 3.6. For this reason, this arrangement of minerals became known as Bowen's reaction series. On the upper left branch of this reaction series, olivine, the first mineral to form, Ml] react with the remaining melt to become pyroxene. This reaction will continue until the last mineral in the series, biotite mica, is formed. This left branch is called a discontinuous reaction series because each mineral has a different crystalline structure. Recall that olivine is composed of a single tetrahedra and that the other minerals in this sequence are composed of single chains, double chains, and sheet structures, respectively. Ordinarily, these reactions are not complete so that various amounts of each of these minerals may exist at any given time.

The right branch of the reaction series is a continuum in which the earliest formed calcium-rich feldspar crystals react with the sodium ions contained in the melt to become progressively more sodium rich. Oftentimes the rate of cooling occurs rapidly enough to prohibit the complete transformation of calcium-rich feldspar into sodium-rich feldspar. In these instances, the feldspar crystals will have calcium-rich interiors surrounded by zones that are progressively richer in sodium. During the last stage of crystallization, after most of the magma has solidified, the remaining melt will form the minerals quartz, muscovite mica, and potassium feldspar. Although these minerals crystallize in the order shown, this sequence is not a true reaction series. Bowen demonstrated that minerals crystallize from magma in a systematic fashion. But how does Bowen's reaction series account for the great diversity of igneous rocks? It appears that at one or more stages in the crystallization process, a separation of the solid and liquid components of a magma frequently occurs. This can happen, for example, if the earlier formed minerals are heavier than the liquid portion and settle to the bottom of the magma chamber as shown in Figure 3.7A. This settling is thought to occur frequently with the dark silicates, such as olivine. When the remaining melt crystallizes, either in place or in a new location if it migrates out of the chamber, it will form a rock with a chemical composition much different from the original magma (Figure 3.7B). In many instances the melt which has migrated from the initial magma chamber will undergo further segregation. As crystallization progresses in the " new" magma, the solid particles may accumulate into rocklike masses surrounded by pockets of the still molten material. It is very likely that some of this melt will be squeezed from the mixture into the cracks which develop in the surrounding rock. This process will generate an igneous rock of yet another composition.

The process involving the segregation of minerals by differential crystallization an separation is called fractional crystallization. At any stage in the crystallization process the melt might be separated from the solid portion of the magma. Consequently, fractional crystallization can produce igneous rocks having a wide range of compositions. Bowen successfully demonstrated that through fractional crystallization one magma can generate several different igneous rocks. However, more recent work has indicated that this process cannot account for the relative quantities of the various rock types known to exist. Although more than one rock type can be generated from a single magma, apparently other mechanisms also exist to generate magmas of quite varied chemical compositions. We will examine some of these mechanisms at the end of the next chapter.

FIGURE 3.7

Separation of minerals by fractional crystallization. A. Illustration of how the earliest formed minerals can be separated from a magma by settling. B. The remaining melt could migrate to a number of different locations and, upon further crystallization, generate rocks having a composition much different from the parent magma.

So we see that many varieties of minerals are produced from the same magma by the different processes of crystallization, and these different minerals may have very different compositions. It is possible that the ratio of daughter to parent substances for radiometric dating could differ in the different minerals. Clearly, it is important to have a good understanding of these processes in order to evaluate the reliability of radiometric dating. Another quotation about fractionation follows:
Faure discusses fractional crystallization relating to U and Th in his book (p. 283) He says, "The abundances of U and Th in chondritic meteorites are 1 x 10^-2 and 4 x 10^-4 ppm, respectively. These values may be taken as an indication of the very low abundance of these elements in the mantle and crust of the Earth. In the course of partial melting and fractional crystallization of magma, U and Th are concentrated in the liquid phase and become incorporated into the more silica-rich products. For that reason, igneous rocks of granitic composition are strongly enriched in U and Th compared to rocks of basaltic or ultramafic composition. Progressive geochemical differentiation of the upper mantle of the Earth has resulted in the concentration of U and Th into the rocks of the continental crust compared to those of the upper mantle."

Faure does say that the Th/U and U/Pb ratios remain virtually constant in the different materials. The concentration of Pb is usually so much higher than U, that a 2- to 3-fold increase of U doesn't change the percent composition much ( e.g. 3.5ppm U/19.6ppm Pb in gneiss vs 1.6ppm U/18.7ppm Pb in granulite, and 4.8ppm U/23.0ppm Pb in granite shows some shifts in composition).

We see that there are at least two kinds of magma, and U and Th get carried along in silica rich magma rather than in basaltic magma. This represents major fractionation. Of course, any process that tends to concentrate or deplete uranium or thorium relative to lead would have an influence on the radiometric ages computed by uranium-lead or thorium-lead dating. Also, the fact that there are two kids of magma could mean that the various radiometric ages are obtained by mixing of these kinds of magma in different proportions, and do not represent true ages at all.
Finally, we have a third quotation from Elaine G. Kennedy in Geoscience Reports, Spring 1997, No. 22, p.8.:

Contamination and fractionation issues are frankly acknowledged by the geologic community.2 For example, if a magma chamber does not have homogeneously mixed isotopes, lighter daughter products could accumulate in the upper portion of the chamber. If this occurs, initial volcanic eruptions would have a preponderance of daughter products relative to the parent isotopes. Such a distribution would give the appearance of age. As the magma chamber is depleted in daughter products, subsequent lava flows and ash beds would have younger dates.

Such a scenario does not answer all of the questions or solve all of the problems that radiometric dating poses for those who believe the Genesis account of Creation and the Flood. It does suggest at least one aspect of the problem that could be researched more thoroughly.

2. G. Faure. 1986. Principles of Isotope Geology: John Wiley and Sons, Inc., NY, 589p.

It is interesting that contamination and fractionation issues are frankly acknowledged by the geologic community. But they may not be so familiar to the readers of talk.origins and other forums where creation and evolution are discussed.
So we have two kinds of processes taking place. There are those processes taking place when lava solidifies and various minerals crystallize out at different times. There are also processes taking place within a magma chamber that can cause differences in the composition of the magma from the top to the bottom of the chamber, since one might expect the temperature at the top to be cooler. Both kinds of processes can influence radiometric dates. In addition, the magma chamber would be expected to be cooler all around its borders, both at the top and the bottom as well as in the horizontal extremities, and these effects must also be taken into account.

For example, heavier substances will tend to sink to the bottom of a magma chamber. Also, substances with a higher melting point will tend to crystallize out at the top of a magma chamber and fall, since it will be cooler at the top. These substances will then fall to the lower portion of the magma chamber, where it is hotter, and remelt. This will make the composition of the magma different at the top and bottom of the chamber. This could influence radiometric dates. This mechanism was suggested by Jon Covey (and others). The solubility of various substances in the magma also could be a function of temperature, and have an influence on the composition of the magma at the top and bottom of the magma chamber. Finally, minerals that crystallize at the top of the chamber and fall may tend to incorporate other substances, and so these other substances will also tend to have a change in concentration from the top to the bottom of the magma chamber.

There are quite a number of mechanisms in operation in a magma chamber. I count at least three so far -- sorting by density, sorting by melting point, and sorting by how easily something is incorporated into minerals that form at the top of a magma chamber. Then you have to remember that sometimes one has repeated melting and solidification, introducing more complications. There is also a fourth mechanism -- differences in solubilities. How anyone can keep track of this all is a mystery to me, especially with the difficulties encountered in exploring magma chambers. These will be definite factors that will change relative concentrations of parent and daughter isotopes in some way, and call into question the reliability of radiometric dating. In fact, I think this is a very telling argument against radiometric dating.

Another possibility to keep in mind is that lead becomes gaseous at low temperatures, and would be gaseous in magma if it were not for the extreme pressures deep in the earth. It also becomes very mobile when hot. These processes could influence the distribution of lead in magma chambers.

Let me suggest how these processes could influence uranium-lead and thorium-lead dates:

The following is a quote from The Earth: An Introduction to Physical Geology by Tarbuck & Lutgens, pp. 55-57, (1987).

"For example, at the stage when about 50 percent of the magma has solidified, the melt will be greatly depleted in iron, magnesium, and calcium, because these elements are found in the earliest formed minerals. But at the same time, it will be enriched in the elements contained in the later forming minerals, namely sodium and potassium."

A geologist writes:

"Uranium and thorium ARE strongly fractionated during magmatic processes and tend to be concentrated in the silicic/felsic part of a magma hence granites and rhyolites tend to have a much higher average uranium and thorium concentration (3-5 ppm U) compared to basalts (less than 1 ppm U)."

From the above quotes and references, uranium is concentrated in granite, which is depleted in magnesium and iron. The magnesium and iron rich minerals come from the mantle (subducted oceanic plates), while granite comes from continental sediments (crustal rock). The mantle part solidifies first, and is rich in magnesium, iron, and calcium. The silicic/felsic part of a magma typically becomes granite and solidifies later, enriched in uranium, thorium, sodium, and potassium. So it is reasonable to expect that initially, the magma is rich in iron, magnesium, and calcium and poor in uranium, thorium, sodium, and potassium. Later on the magma is poor in iron, magnesium, and calcium and rich in uranium, thorium, sodium, and potassium. It doesn't say which class lead is in. But lead is a metal, and to me it looks more likely that lead would concentrate along with the iron. If this is so, the magma would initially be poor in thorium and uranium and rich in lead, and as it cooled it would become rich in thorium and uranium and poor in lead. Thus its radiometric age would tend to decrease rapidly with time, and lava emitted later would tend to look younger.

Another point is that of time. Suppose that the uranium does come to the top by whatever reason. Perhaps magma that is uranium rich tends to be lighter than other magma. Or maybe the uranium poor rocks crystallize out first and the remaining magma is enriched in uranium. Would this cause trouble for our explanation? Not necessarily. It depends how fast it happened. If it happened slowly with respect to the flood or whatever, then the uranium concentration could be rising with time, and this would tend to make the newer magma look younger since its U/Pb ratio would be higher.

Some information from the book Uranium Geochemistry, Mineralogy, Geology provided by Jon Covey gives us evidence that fractionation processes are making radiometric dates much, much too old. Geology contributing author Massimo Cortini cites a very interesting anomaly regarding the U 238 decay chain, which is U-238, U-234, Th-230, Ra-226, Rn-222, Po-218 Po-214, Po-210, Pb-210, Bi-210, Pb-206. The half life of U-238 is 4.47 x 10^9 years and that of Ra-226 is 1.6 x 10^3 years. Thus radium is decaying 3 million times as fast as U-238. At equilibrium, which should be attained in 500,000 years for this decay series, we should expect to have 3 million times as much U-238 as radium to equalize the amount of daughter produced. Cortini says geologists discovered that ten times more Ra-226 than the equilibrium value was present in rocks from Vesuvius. They found similar excess radium at Mount St. Helens, Vulcanello, and Lipari and other volcanic sites. The only place where radioactive equilibrium of the U-238 series exists in zero age lavas is in Hawiian rocks. Thus instead of having 1/(3 million) as much radium as uranium, which we should expect, there is ten times as much, or 1/(300,000) times as much radium as uranium.

We need to consider the implications of this for radiometric dating. How is this excess of radium being produced? This radium cannot be the result of decay of uranium, since there is far too much of it. Either it is the result of an unknown decay process, or it is the result of fractionation which is greatly increasing the concentration of radium or greatly decreasing the concentration of uranium. Thus only a small fraction of the radium present in the lava (at most 10 percent) is the result of decay of the uranium in the lava.

This is interesting because both radium and lead are daughter products of uranium. If similar fractionation processes are operating for lead, this would mean that only a small fraction of the lead is the result of decay from the parent uranium, implying that the U-Pb radiometric dates are much, much too old. Cortini, in an article appearing in the Journal of Volcanology and Geothermal Research also suggests this possibility. He says:

"The invalidity of the Th-230 dating method is a consequence of the open-system behaviour of U and Th. By analogy with the behaviour of Ra, Th and U it can be suggested that Pb, owing to its large mobility, was also fed to the magma by fluids. This can and must be tested. The open-system behaviour of Pb, if true, would have dramatic consequences...." J Vol Geotherm Res 14 (1982) 247-260.

On the other hand, even if such a process is not operating for lead, the extra radium will decay rapidly to lead, and so in either case we have much too much lead in the lava and radiometric dates that are much, much too ancient! So this is a clue that something is not right with U-238/Pb-206 radiometric dates. It is also a convincing proof that some kind of drastic fractionation is taking place, or else an unknown process is responsible. Since most lavas have excess radium today, it is reasonable to assume this has always been true, and that all U-238/Pb-206 radiometric dates are much, much too old. Cortini says high Ra-226/U-238 ratios are a common feature of primitive magmas, which magma-generating processes produce. He says this is inexplicable in a closed-system framework and certainly invalidates the Th-230 dating method. And it is also possible that something similar is happening in the U-235 decay chain, invalidating U-235 based radiometric dates as well.
In fact, U-235 and Th-232 both have isotopes of radium in their decay chains with half lives of a week or two, and 6.7 years, respectively. Any process that is concentrating one isotope of radium will probably concentrate the others as well and invalidate these dating methods, too. Radium 226 has a low melting point (973 degrees K) which may account for its concentration at the top of magma chambers.

What radiometric dating needs to do to show its reliability is to demonstrate that no such fractionation could take place. Can this be done? With so many unknowns I don't think so.


How Uranium and Thorium are preferentially incorporated in various minerals
I now give evidences that uranium and thorium are incorporated into some minerals more than others. This is not necessarily a problem for radiometric dating, because it can be taken into account. But as we saw above, processes that take place within magma chambers involving crystallization could result in a different concentration of uranium and thorium at the top of a magma chamber than at the bottom. This can happen because different minerals incorporate different amounts of uranium and thorium, and these different minerals also have different melting points and different densities. If minerals that crystallize at the top of a magma chamber and fall, tend to incorporate a lot of uranium, this will tend to deplete uranium at the top of the magma chamber, and make the magma there look older.
Concerning the distribution of parent and daughter isotopes in various substances, there are appreciable differences. Faure shows that in granite U is 4.8 ppm while Pb is 23 ppm, while in andesite U is 2.4 ppm and Pb is 5.8. Some process is causing the differences in the ratios of these magmatic rocks.

Depending on their oxidation state, according to Faure, uranium minerals can be very soluble in water while thorium compounds are, generally, very insoluble. These elements also show preferences for the minerals in which they are incorporated, so that they will tend to be "dissolved" in certain mineral "solutions" preferentially to one another. More U is found in carbonate rocks, while Th has a very strong preference for granites in comparison.

I saw a reference that uranium reacts strongly, and is never found pure in nature. So the question is what the melting points of its oxides or salts would be, I suppose. I also saw a statement that uranium is abundant in the crust, but never found in high concentrations. To me this indicates a high melting point for its minerals, as those with a low melting point might be expected to concentrate in the magma remaining after others crystallized out. (Such a high melting point would imply fractionation in the magma.) Thorium is close to uranium in the periodic table, so it may have similar properties, and similar remarks may apply to it.

It turns out that uranium in magma is typically found in the form of uranium dioxide, with a melting point of 2878 degrees centrigrade. (CRC Handbook of Chemistry and Physics 72 ed., 1992 (55th edition also)). This high melting point suggests that uranium would crystallize and fall to the bottom of magma chambers.

Geologists are aware of the problem of initial concentration of daughter elements, and attempt to take it into account. U-Pb dating attempts to get around the lack of information about initial daughter concentrations by the choice of minerals that are dated. For example, zircons are thought to accept little lead but much uranium. Thus geologists assume that the lead in zircons resulted from radioactive decay. But I don't know how they can be sure how much lead zircons accept, and even they admit that zircons accept some lead. Lead could easily reside in impurities and imperfections in the crystal structure. Also, John Woodmorappe's paper has some examples of anomalies involving zircons.

It is known that the crystal structure of zircons does not accept much lead. However, it is unrealistic to expect a pure crystal to form in nature. Perfect crystals are very rare. In reality, I would expect that crystal growth would be blocked locally by various things, possibly particles in the way. Then the surrounding crystal surface would continue to grow and close up the gap, incorporating a tiny amount of magma. I even read something about geologists trying to choose crystals without impurities (by visual examination) when doing radiometric dating. Thus we can assume that zircons would incorporate some lead in their impurities, potentially invalidating uranium-lead dates obtained from zircons.

Chemical fractionation, as we have seen, calls radiometric dates into question. But this cannot explain the distribution of lead isotopes. There are actually several isotopes of lead that are produced by different parent substances (uranium 238, uranium 235, and thorium). One would not expect there to be much difference in the concentration of lead isotopes due to fractionation, since isotopes have properties that are very similar. So one could argue that any variations in Pb ratios would have to result from radioactive decay. However, the composition of lead isotopes between magma chambers could still differ, and lead could be incorporated into lava as it traveled to the surface from surrounding materials. I also recall reading that geologists assume the initial Pb isotope ratios vary from place to place anyway. Later we will see that mixing of two kinds of magma, with different proportions of lead isotopes, could also lead to differences in concentrations.


Mechanism of uranium crystallization and falling through the magma
We now consider in more detail the process of fractionation that can cause uranium to be depleted at the top of magma chambers. Uranium and thorium have high melting points and as magma cools, these elements crystallize out of solution and fall to the magma chamber's depths and remelt. This process is known as fractional crystallization. What this does is deplete the upper parts of the chamber of uranium and thorium, leaving the radiogenic lead. As this material leaves, that which is first out will be high in lead and low in parent isotopes. This will date oldest. Magma escaping later will date younger because it is enriched in U and Th. There will be a concordance or agreement in dates obtained by these seemingly very different dating methods. This mechanism was suggested by Jon Covey.
Tarbuck and Lutgens carefully explain the process of fractional crystallization in The Earth: An Introduction to Physical Geology. They show clear drawings of crystallized minerals falling through the magma and explain that the crystallized minerals do indeed fall through the magma chamber. Further, most minerals of uranium and thorium are denser than other minerals, especially when those minerals are in the liquid phase. Crystalline solids tend to be denser than liquids from which they came. But the degree to which they are incorporated in other minerals with high melting points might have a greater influence, since the concentrations of uranium and thorium are so low.

Now another issue is simply the atomic weight of uranium and thorium, which is high. Any compound containing them is also likely to be heavy and sink to the bottom relative to others, even in a liquid form. If there is significant convection in the magma, this would be minimized, however.

At any rate, there will be some effects of this nature that will produce some kinds of changes in concentration of uranium and thorium relative to lead from the top to the bottom of a magma chamber. Some of the patterns that are produced may appear to give valid radiometric dates. Others may not. The latter may be explained away due to various mechanisms.

Let us consider processes that could cause uranium and thorium to be incorporated into minerals with a high melting point. I read that zircons absorb uranium, but not much lead. Thus they are used for U-Pb dating. But many minerals take in a lot of uranium. It is also known that uranium is highly reactive. To me this suggests that it is eager to give up its 2 outer electrons. This would tend to produce compounds with a high dipole moment, with a positive charge on uranium and a negative charge on the other elements. This would in turn tend to produce a high melting point, since the atoms would attract one another electrostatically. (I'm guessing a little bit here.) There are a number of uranium compounds with different melting points, and in general it seems that the ones with the highest melting points are more stable. I would suppose that in magma, due to reactions, most of the uranium would end up in the most stable compounds with the highest melting points. These would also tend to have high dipole moments.

Now, this would also help the uranium to be incorporated into other minerals. The electric charge distribution would create an attraction between the uranium compound and a crystallizing mineral, enabling uranium to be incorporated. But this would be less so for lead, which reacts less strongly, and probably is not incorporated so easily into minerals. So in the minerals crystallizing at the top of the magma, uranium would be taken in more than lead. These minerals would then fall to the bottom of the magma chamber and thus uranium at the top would be depleted. It doesn't matter if these minerals are relatively lighter than others. The point is that they are heavier than the magma.


Two kinds of magma and implications for radiometric dating
It turns out that magma has two sources, ocean plates and material from the continents (crustal rock). This fact has profound implications for radiometric dating.
Mantle material is very low in uranium and thorium, having only 0.004 ppm, while crustal rock has 1.4 ppm, according to Richard Arculus in a paper he presented at the Uranium Institute Mid-Term Meeting in Adelaide, 1996 (see http://www.uilondon.org for further information and the article). The source of magma for volcanic activity is subducted oceanic plates. Subduction means that these plates are pushed under the continents by motions of the earth's crust. While oceanic plates are basaltic (mafic) originating from the mid-oceanic ridges due to partial melting of mantle rock, the material that is magma is a combination of oceanic plate material and continental sediments. Subducted oceanic plates begin to melt when they reach depths of about 125 kilometers (See Tarbuck, The Earth, p. 102). In other words, mantle is not the direct source of magma.

Granite and rhyolite never arise from mantle even if granite has a magmatic origin because the upwelling melted mantle material produces basalts which are enriched in magnesium (Mg) and iron (Fe), which is why it is classified as mafic (MAgnesium + the F of Fe).

Further, Faure explains that uraninite (UO sub2) is a component of igneous rocks (Faure, p. 290), i.e., those rocks that form from cooling magma, the source of which is not mantle but subducted and melted oceanic plate and continental sediments eroded from all types of continental rocks. Uraninite is also known as pitchblende.

The following is taken from "WHAT HAPPENS WHEN ROCKS MELT?" by Elaine G. Kennedy.

According to plate tectonic theory, continental crust overrides oceanic crust when these plates collide because the continental crust is less dense than the ocean floor. As the ocean floor sinks, it encounters increasing pressures and temperatures within the crust. Ultimately, the pressures and temperatures are so high that the rocks in the subducted oceanic crust melt. Once the rocks melt, a plume of molten material begins to rise in the crust. As the plume rises it melts and incorporates other crustal rocks. This rising body of magma is an open system with respect to the surrounding crustal rocks.1 Convection currents stir the magma. Volatiles (e.g., water vapor and carbon dioxide) increase the pressure within the magma chamber and contribute to the mixing of the system.

It is possible that these physical processes have an impact on the determined radiometric age of the rock as it cools and crystallizes. Time is not a direct measurement. The actual data are the ratios of parent and daughter isotopes present in the sample. Time is one of the values that can be determined from the slope of the line representing the distribution of the isotopes. Isotope distributions are determined by the chemical and physical factors governing a given magma chamber.

Uranium is believed to be able to incorporate itself as a trace material in many other minerals of low density, and so be relatively highly concentrated in the crust. A lower mantle concentration of uranium is inferred because if the mantle contained the same uranium concentration as the crust, then the uranium's heat of radiactive decay would keep the crust molten.
A geologist writes, "Uranium and thorium ARE strongly fractionated during magmatic processes and tend to be concentrated in the silicic/felsic part of a magma hence granites and rhyolites tend to have a much higher average uranium and thorium concentration (3-5 ppm U) compared to basalts (less than 1 ppm U). Some granites in New Hampshire, Arizona, Washington State, Colorado, and Wyoming range from 10-30 ppm U. Rhyolites in Yellowstone N.P. average about 7 ppm U. Most genetic models for uranium deposits in sandstones in the U.S. require a granitic or silicic volcanic source rock to provide the uranium. Most of the uranium deposits in Wyoming are formed from uraniferous groundwaters derived from Precambrian granitic terranes. Uranium in the major uranium deposits in the San Juan basin of New Mexico is believed to have been derived from silicic volcanic ash from Jurassic island arcs at the edge of the continent. An excellent reference to hydrothermal uranium deposits and magmatic processes involving uranium is a book by Vladimir Ruzicka entitled `Hydrothermal Uranium Deposits'".

From the above sources, we see that another factor influencing radiometric dates is the proportion of the magma that comes from subducted oceanic plates and the proportion that comes from crustal rock. Initially, we would expect most of it to come from subducted oceanic plates, which are uranium and thorium poor and maybe lead rich. Later, more of the crustal rock would be incorporated by melting into the magma, and thus the magma would be richer in uranium and thorium and poorer in lead. So this factor would also make the age appear to become younger with time.

There are two kinds of magma, and the crustal material which is enriched in uranium also tends to be lighter. For our topic on radiometric dating and fractional crystallization, there is nothing that would prevent uranium and thorium ores from crystallizing within the upper, lighter portion of the magma chamber and descending to the lower boundaries of the sialic portion. The upper portion of the sialic magma would be cooler since its in contact with continental rock, and the high melting point of UO sub 2 (uranium dioxide, the common form in granite: mp = 2878 C) would assure that this mineral would crystallize as the magma body ascends into the cool lithosphere. The same kind of fractional crystallization would be true of non-granitic melts.

I think we can build a strong case for fictitious ages in magmatic rocks as a result of fractional cystallization and geochemical processes. As we have seen, we cannot ignore geochemical effects while we consider geophysical effects. Sialic (granitic) and mafic (basaltic) magma are separated from each other, with uranium and thorium chemically predestined to reside mainly in sialic magma and less in mafic rock.

Here is yet another mechanism that can cause trouble for radiometric dating: As lava rises through the crust, it will heat up surrounding rock. Lead has a low melting point, so it will melt early and enter the magma. This will cause an apparent large age. Uranium has a much higher melting point. It will enter later, probably due to melting of materials in which it is embedded. This will tend to lower the ages.


Mechanisms that can create isochrons giving meaningless ages:
Geologists attempt to estimate the initial concentration of daughter product by a clever device called an isochron. Let me make some general comments about isochrons.
The idea of isochrons is that one has a parent element, P, a daughter element, D, and another isotope, N, of the daughter that is not generated by decay. One would assume that initially, the concentration of N and D in different locations are proportional, since their chemical properties are very similar. Note that this assumption implies a thorough mixing and melting of the magma, which would also mix in the parent substances as well. Then we require some process to preferentially concentrate the parent substances in certain places. Radioactive decay would generate a concentration of D proportional to P. So after the passing of millions of years of assumed time, we would obtain an equation of the form

d = c1*p + c2*n
where p, d, and n are the concentrations of P, D, and N after some time period. The quantity c1*p represents the D generated by radioactive decay, and the c2*N representes the amount present originally. By taking enough measurements of the concentrations of P, D, and N, we can solve for c1 and c2, and from c1 we can determine the radiometric age of the sample. But we can only solve if the ratio p/n varies. Otherwise, the system is degenerate. Thus we need to have an uneven distribution of D relative to N at the start.

The ratios p/n and d/n have a linear relationship whose slope yields the age of the sample. If these ratios are observed to obey such a linear relationship in a series of rocks, then an age can be computed from them. The age will be the same as the age of a rock with d = c1*n, assuming that all of the daughter element D arose by radioactive decay from P. The bigger c1 is, the older the rock is. That is, the more daughter product relative to parent product, the greater the age. Thus we have the same general situation as with simiple parent-to-daughter computations, more daughter product implies an older age.

This is a very clever idea. However, there are some problems with it.

First, in order to have a meaningful isochron, it is necessary to have an unusual chain of events. Initially, one has to have a uniform ratio of lead isotopes in the magma. Usually the concentration of uranium and thorium varies in different places in rock. This will, over the assumed millions of years, produce uneven concentrations of lead isotopes. To even this out, one has to have a thorough mixing of the magma. Even this is problematical, unless the magma is very hot, and no external material enters. Now, after the magma is thoroughly mixed, the uranium and thorium will also be thoroughly mixed. If this condition remains, one gets an isochron in which all samples yield the same (p/n,d/n) values, and one gets just a single point, which does not yield an age. What has to happen next to get an isochron is that the uranium or thorium has to concentrate relative to the lead isotopes, more in some places than others. So this implies some kind of chemical fractionation. Then the system has to remain closed for a long time. This chemical fractionation will most likely arise by some minerals incorporating more or less uranium or thorium relative to lead.

Anyway, to me it seems unlikely that this chain of events would occur.

Another problem with isochrons is that they can occur by mixing and other processes that result in isochrons yielding meaningless ages. Sometimes, according to Faure, what seems to be an isochron is actually a mixing line, a leftover from differentiation in the magma. Fractionation followed by mixing can create isochrons giving too old ages, without any fractionation of daughter isotopes taking place. To get an isochron with a false age, all you need is (1) too much daughter element, due to some kind of fractionation and (2) mixing of this with something else that fractionated differently. Since fractionation and mixing are so common, we should expect to find isochrons often. How they correlate with the expected ages of their geologic period is an interesting question. There are at least some outstanding anomalies.

Faure states that chemical fractionation produces "fictitious isochrons whose slopes have no time significance." Faure explains how fictitious isochrons develop as a result of fractionation in lava flows. As an example, he uses Pliocene to Recent lava flows and from lava flows in historical times to illustrate the problem. He says, these flows should have slopes approaching zero(less than 1 million years), but they instead appear to be much older (773 million years). Steve Austin has found lava rocks on the Uinkeret Plateau at Grand Canyon with fictitious isochrons dating at 1.5 billion years, making them 0.5 to 1.0 billion years older than the deeply emplaced sediments. Faure explains that this situation actually represents a mixing line, the isotope ratios of Rb/Sr resulting from a mixing process, interpretable as evidence of long-term heterogeneity of the upper mantle (Faure, 145-147).

Suppose sample A has d = c1*p and a given concentration of N. Suppose sample B has no P or D but the same concentration of N as A. Then a mixing of A and B will have the same fixed concentration of N everywhere, but the amount of D will be proportional to the amount of P. This produces an isochron yielding the same age as sample A.

This is a reasonable scenario, since N is a non-radiogenic isotope (not produced by decay) such as lead 204, and it can be assumed to have similar concentrations in many magmas. Magma from the ocean floor has little U238 and little U235 and probably little lead byproducts lead 206 and lead 207. Magma from melted continental material probably has more of both U238 and U235 and lead 206 and lead 207. Thus we can get an isochron by mixing, that has the age of the younger-looking continental crust. The age will not even depend on how much crust is incorporated, as long as it is non-zero.

However, if the crust is enriched in lead or impoverished in uranium before the mixing, then the age of the isochron will be increased. If the reverse happens before mixing, the age of the isochron will be decreased. Any process that enriches or impoverishes part of the magma in lead or uranium before such a mixing will have a similar effect. So all of the scenarios given before can also yield spurious isochrons.

I hope that this discussion will dispel the idea that there is something magical about isochrons that prevents spurious dates from being obtained by enrichment or depletion of parent or daughter elements as one would expect by common sense reasoning. So all the mechanisms mentioned earlier are capable of producing isochrons with ages that are too old, or that decrease rapidly with time. The conclusion is the same, radiometric dating is in trouble.

I now describe this mixing in more detail. Suppose P(p) is the concentration of parent at a point p in a rock. The point p specifies x,y, and z co-ordinates. Let D(p) be the concentration of daughter at the point p. Let N(p) be the concentration of some non-radiogenic (not generated by radioactive decay) isotope of D at point p. For U-238 Pb-206 dating, P would be U-238 and D would be Pb-206 and N would be Pb-204.

Suppose this rock is obtained by mixing of two other rocks, A and B. Suppose that A has a (for the sake of argument, uniform) concentration of P1 of parent, D1 of daughter, and N1 of non-radiogenic isotope of the daughter. Thus P1, D1, and N1 are numbers between 0 and 1 whose sum adds to less than 1. Suppose B has concentrations P2, D2, and N2. Let r(p) be the fraction of A at any given point p in the mixture. Thus if r(p) is 1/3, the mixture has 1/3 A and 2/3 B at point p. Then

P(p) = r(p)*P1 + (1-r(p))*P2
D(p) = r(p)*D1 + (1-r(p))*D2

N(p) = r(p)*N1 + (1-r(p))*N2

Now, to have an isochron we need to have constants c1 and c2 independent of p such that for all p,

D(p) = c1*P(p) + c2*N(p)
This can happen if P2 = 0 and N1 = N2 and D1 > D2. Then we have

P(p) = r(p)*P1
D(p) = r(p)*D1 + (1-r(p))*D2 = r(p)*(D1-D2) + D2

N(p) = r(p)*N1 + (1-r(p))*N2 = N1 = N2.

We can choose c1 = (D1-D2)/P1 and c2 = D2/N2 and the formula D(p) = c1*P(p) + c2*N(p) works out (if I didn't make any errors).

So this is a mixing that yields an isochron giving an age corresponding to a daughter to parent ratio of (D1-D2)/P1, which is less than the daughter to parent ratio of rock A, which is D1/P1. However, it is still positive, since D1 > D2, and it still increases as D1 increases and decreases as P1 increases. So the usual methods for augmenting and depleting parent and daughter substances still work to influence the age of this isochron. More daughter product means an older age, and less daughter product (relative to parent) means a younger age. And I think the assumptions P2 = 0 and N1 = N2 and D1 > D2 are reasonable, since the substance N, lead 204, is probably of nearly constant concentration in many magmas. This corresponds to the condition N1=N2. It's also reasonable to think that the crustal material from continents is enriched in both parent and daughter product relative to the ocean floor, corresponding to the condition D1 > D2, and we know that the ocean floor is very poor in parent material (uranium in this case). This corresponds to the condition P2 = 0.

In fact, more is true. Any isochron whatever with a positive age and a constant concentration of N can be constructed by such a mixing. It is only necessary to choose r(p) and P1, N1, and N2 so as to make P(p) and D(p) agree with the observed values, and there is enough freedom to do this.

Anyway, to sum up, there are many processes that can produce a rock or magma A having a spurious parent-to-daughter ratio. Then from mixing, one can produce an isochron having a spurious age. This shows that computed radiometric ages, even isochrons, do not have any necessary relation to true geologic ages.

Mixing can produce isochrons giving false ages. This can be detected _sometimes_. But anyway, let's suppose we only consider isochrons for which mixing cannot be detected. How do their ages agree with the assumed ages of their geologic periods? As far as I know, it's anyone's guess, but I'd appreciate more information on this. I believe that the same considerations apply to concordia and discordia, but am not as familiar with them.

It's interesting that isochrons depend on chemical fractionation for their validity. They assume that initially the magma was well mixed to assure an even concentration of lead isotopes, but that uranium or thorium were unevenly distributed initially. So this assumes at the start that chemical fractionation is operating. But these same chemical fractionation processes call radiometric dating into question.

The relative concentrations of lead isotopes are measured in the vicinity of a rock. The amount of radiogenic lead is measured by seeing how the lead in the rock differs in isotope composition from the lead around the rock. This is actually a good argument. But, is this test always done? How often is it done? And what does one mean by the vicinity of the rock? How big is a vicinity? One could say that some of the radiogenic lead has diffused into neighboring rocks, too. Some of the neighboring rocks may have uranium and thorium as well (although this can be factored in in an isochron-type manner). Furthermore, I believe that mixing can also invalidate this test, since it is essentially an isochron. Finally, if one only considers U-Pb and Th-Pb dates for which this test is done, and for which mixing cannot be detected. how do they correlate with other dates and with conventional ages?

The above two-source mixing scenario is limited, because it can only produce isochrons having a fixed concentration of N(p). To produce isochrons having a variable N(p), a mixing of three sources would suffice. This could produce an arbitrary isochron, so this mixing could not be detected.

Also, it seems unrealistic to say that a geologist would discard any isochron with a constant value of N(p), as it seems to be a very natural condition (at least for whole rock isochrons), and not necessarily to indicate mixing. And it's not clear to me in any case that just because an isochron gives evidence that it _could_ have been produced by a mixing of two sources, that it would always be discarded.

I now show that the mixing of three sources can produce an isochron that could not be detected by the mixing test. First let me note that there is a lot more going on than just mixing. There can also be fractionation that might treat the parent and daughter products identically, and thus preserve the isochron, while changing the concentrations so as to cause the mixing test to fail. It is not even necessary for the fractionation to treat parent and daughter equally, as long as it has the same preference for one over the other in all minerals examined; this will also preserve the isochron.

Now, suppose we have an arbitrary isochron with concentrations of parent, daughter, and non-radiogenic isotope of the daughter as P(p), D(p), and N(p) at point p. Then we have the relationship

D(p) = c1*P(p) + c2*N(p)
which guarantees that an isochron exists. Suppose that the rock is then diluted with another source which does not contain any of D, P, or N. Then these concentrations would be reduced by a factor of say r'(p) at point p, and so the new concentrations would be P(p)r'(p), D(p)r'(p), and N(p)r'(p) at point p. These still satisfy the isochron relationship at each point, since

D(p)r'(p) = c1*P(p)r'(p) + c2*N(p)r'(p)
Thus one again obtains an isochron, but the concentration of N(p) has been changed at each point.

Now, earlier I stated that an arbitrary isochron with a fixed concentration of N(p) could be obtained by mixing of two sources, both having a fixed concentration of N(p). With mixing from a third source as indicated above, we obtain an isochron with a variable concentration of N(p), and in fact an arbitrary isochron can be obtained in this manner.

So we see that it is actually not much harder to get an isochron yielding a given age than it is to get a single rock yielding a given age. This can happen by mixing scenarios as indicated above. Thus all of our scenarios for producing spurious parent-to-daughter ratios can be extended to yield spurious isochrons.

The condition that one of the sources have no P, D, or N is fairly natural, I think, because of the various fractionations that can produce very different kinds of magma, and because of crustal materials of various kinds melting and entering the magma. In fact, considering all of the processes going on in magma, it would seem that such mixing processes and pseudo-isochrons would be guaranteed to occur. Even if one of the sources has only tiny amounts of P, D, and N, it would still produce a reasonably good isochron as indicated above, and this isochron could not be detected by the mixing test.

I now give a more natural three-source mixing scenario that can produce an arbitrary isochron, which could not be detected by a mixing test. Suppose we have three sources with concentrations of parent, daughter, and non-radiogenic isotope of daughter of Pi, Di, Ni, respectively, for i = 1,2,3. Suppose

D2/N2 and D3/N3 are very close
P2 and P3 are very small
D1/N1 > D2/N2
P1 is large
This is plausible, since we generally assume the isotopes of lead (say) have a roughly constant ratio everywhere. For sample 1, with more parent, we expect more daughter, so D1/N1 > D2/N2. P2 and P3 are small, since some rocks will have little parent substance. Suppose also that N2 and N3 differ significantly.

Such mixings can produce arbitrary isochrons, so these cannot be detected by any mixing test.

Also, if P1 is reduced by fractionation prior to mixing, this will make the age larger. If P1 is increased, it will make the age smaller. If P1 is not changed, the age will at least have geological significance. But it could be measuring the apparent age of the ocean floor or crustal material rather than the time of the lava flow.

I believe that the above shows the 3 source mixing to be natural and likely.

We now show in more detail that we can get an arbitrary isochron by a mixing of three sources. Thus such mixings cannot be detected by a mixing test.

We want to create an arbitrary isochron with

D(p) = c1*P(p) + c2*N(p) (1)
Assume D1, P1, and N1 are the concentrations of daughter, parent, and non-radiogenic isotope of the daughter in source 1, with N1 = 0. Assume D2, P2, and N2 in source 2, with P2 = 0. Assume D3, P3, and N3 in source 3, all zero.
Suppose D1 = c1*P1, both chosen as large as possible.

Suppose D2 = c2*N2, both chosen as large as possible.

Thus D1 + P1 = 1, and D2 + N2 = 1.

Thus c1*P1 + P1 = 1, so P1 = 1/(1+c1) and D1 = c1/(1+c1). (2)

Also, c2*N2 + N2 = 1, so N2 = 1/(1+c2) and D2 = c2/(1+c2). (3)

This scenario is unrealistic, since the concentrations are large, but makes the math simpler. One can get this mixing to work with smaller concentrations, too.

To get the mixing, dilute source 1 by P(p)/P1 at point p, and dilute source 2 by N(p)/N2 at point p. All the rest of the mixing comes from source 3.

This produces a mixing with concentration of P at point p of (P(p)/P1) * P1 = P(p), and similarly for N(p) and D(p). Thus we produce the desired isochron.

Claim: P(p)/P1 + N(p)/N2 is at most 1, so this is a valid mixing.

Proof: P(p)/P1 = P(p)*(1+c1) by (2). N(p)/N2 = N(p)*(1+c2) by (3).

Their sum is P(p) + c1*P(p) + N(p) + c2*N(p), which equals P(p) + N(p) + D(p) by (1), which is less than or equal to one.

So this is a valid mixing, and we are done.

We can get more realistic mixings of three sources with the same result by choosing the sources to be linear combinations of sources 1, 2, and 3 above, with more natural concentrations of D, P, and N. For example, let m be the maximum value of D(p) + P(p) + N(p) for any p in the sample. Then we can choose

P1 = m/(1+c1) and D1 = c1*m/(1+c1)

N2 = m/(1+c2) and D2 = c2*m/(1+c2).

The two sources can then still mix to produce the original isochron, with the concentration of source 1 at a point p being P(p)/P1 and the concentration of source 2 at the point p being N(p)/N2. The rest of the mixing comes from source 3. This mixing is more realistic because P1, N1, D2, and N2 are not so large.

I did see in one reference the statement that some parent-to-daughter ratio yielded more accurate dates than isochrons. To me, this suggests the possibility that geologists themselves recognize the problems with isochrons, and are looking for a better method. The impression I have is that geologists are continually looking for new methods, hoping to find something that will avoid problems with existing methods. But then problems also arise with the new methods, and so the search goes on.

Furthermore, here is a brief excerpt from a recent article which also indicates that isochrons often have severe problems. If all of these isochrons indicated mixing, one would think that this would have been mentioned:

The geological literature is filled with references to Rb-Sr isochron ages that are questionable, and even impossible. Woodmorappe (1979, pp. 125-129) cites about 65 references to the problem. Faure (1977, pp. 97-105) devotes this chapter to seven possible causes for "fictitious" isochrons. Zheng (1989, pp. 15-16) also cites 42 references.

Zheng (pp. 2-3, 5) also discusses the frequent occurrence of a variable Sr-86 (another non-radioactive isotope of strontium) that is critical to the situation. He comes closest to recognizing the fact that the Sr-86 concentration is a third or confounding variable in the isochron simple linear regression. Austin (1994, 1992, 1988), Butler (1982), and Dodson (1982) also discuss the discordant and long ages given by the Rb/Sr isochron. Snelling (1994) discusses numerous false ages in the U-Pb system where isochrons are also used. However, the U-Th-Pb method uses a different procedure that I have not examined and for which I have no data. Many of the above authors attempt to explain these "fictitious" ages by resorting to the mixing of several sources of magma containing different amounts of Rb-87, Sr-87, and Sr-86 immediately before the formation hardens. Akridge (1982), Armstrong (1983), Arndts (1983), Brown (1986, 1994), Helmick and Baumann (1989) all discuss this factor in detail.

This is from "A SUFFICIENT REASON FOR FALSE RB-SR ISOCHRONS" by G. HERBERT GILL, Creation Research Society Quarterly, Volume 33, September 1996.
Anyway, if isochrons producing meaningless ages can be produced by mixing, and this mixing cannot be detected if three (or maybe even two, with fractionation) sources are involved, and if mixing frequently occurs, and if simple parent-to-daughter dating also has severe problems, as mentioned earlier, then I would conclude that the reliability of radiometric dating is open to serious question. The many acknowledged anomalies in radiometric dating only add weight to this argument. I would also mention that there are some parent-to-daughter ratios and some isochrons that yield ages in the thousands of years for the geologic column, as one would expect if it is in fact very young.

One might question why we do not have more isochrons with negative slopes if so many isochrons were caused by mixing. This depends on the nature of the samples that mix. It is not necessarily true that one will get the same number of negative as positive slopes. If I have a rock X with lots of uranium and lead daughter isotope, and rock Y with less of both (relative to non-radiogenic lead), then one will get an isochron with a positive slope. If rock X has lots of uranium and little daughter product, and rock Y has little uranium and lots of lead daughter product (relative to non-radiogenic lead), then one will get a negative slope. This last case may be very rare because of the relative concentrations of uranium and lead in crustal material and subducted oceanic plates. I note that there are _some_ isochrons with negative slopes.

Another interesting fact is that isochrons can be inherited from magma into minerals. Earlier, I indicated how crystals can have defects or imperfections in which small amounts of magma can be trapped. This can result in dates being inherited from magma into minerals. This can also result in isochrons being inherited in the same way. So the isochron can be measuring an older age than the time at which the magma solidified.

This can happen also if the magma is not thoroughly mixed when it erupts. If this happens, the isochron can be measuring an age older than the date of the eruption. This is how geologists explain away the old isochron at the top of the Grand Canyon.

From my reading, isochrons are generally not done, as they are expensive. Isochrons require more measurements than single parent-to-daughter ratios, so most dates are based on parent-to-daughter ratios. So all of the scenarios given apply to this large class of dates. Another thing to keep in mind is that it is not always possible to do an isochron. Often one does not get a straight line for the values. This is taken to imply re-melting after the initial solidification, or some other disturbing event. Anyway, this also reduces the number of data points obtained from isochrons.

Anyway, suppose we throw out all isochrons for which mixing seems to be a possibility. What is the distribution of the _remaining_ dates? Due to some published anomalies, I don't think we know that they have any clear relationship to the assumed dates.

It is also interesting that the points for isochrons are sometimes selected so as to obtain the isochron property, according to John Woodmorappe's paper.


Do the various methods correlate with one another?
We have been trying to give mechanisms that explain how the different dating methods can give dates that agree with one another, if the geologic column is young. However, it is not even clear that U/Pb and Th/Pb radiometric ages vary systematically with position in the geologic column, so the whole issue may be moot. But if there is a variation, such effects could help to explain it. It's not only a matter of incorporation in minerals either, as one sometimes does whole rock isochrons and I suppose parent-daughter ratios of whole rock, which would reflect the composition of the magma and not the incorporation into minerals.
We all seem to have this image in our mind of the various dating methods agreeing with each other and also with the accepted age of their geologic periods. So we are investing a lot of time and energy to explain how this marvelous agreement of the various methods can arise in a creationist framework.

The really funny thing to me is that it is very possible that we are trying to explain a phantom of our imagination. The real radiomatric dating methods are often very badly behaved, and often disagree with one another as well as with the assumed ages of their geological periods. It would really be nice if geologists would just do a double blind study sometime to find out what the distributions of the ages are. In practice, geologists carefully select what rocks they will date, and have many explanations for discordant dates, so it's not clear how such a study could be done, but it might be a good project for creationists. There is also evidence that many anomalies are never reported.

Concerning the geologic time scale, Brown writes:

"The construction of this time scale was based on about 380 radioisotope ages that were selected because of their agreement with the presumed fossil and geological sequences found in the rocks. Radioisotope ages that did not meet these requirements were rejected on the basis of presumed chemical and/or physical modifications that made the "ages" unreliable indicators of real time. About 85% of the selections were K-Ar date s, 8% rubidium-strontium dates, and 4% uranium-lead dates."

So we see that only a tiny proportion of these dates on which geologic time was based, were uranium-lead dates. Maybe only 15 in all. Why is this? It is possible that the reason is that uranium-lead dates so rarely agree with the correct dates. So there may not be anything to explain.

For example, it's not clear to me that we need to worry about isochrons or whether U238 and U235 dates etc. agree with each other. I'd like to know how often this happens, in any case, especially on the geologic column of Cambrian and above. People should read John Woodmorappe's articles on radiometric dating to see some of the anomalies.

One might say that if there were problems, then geologists wouldn't use these methods. I think we need something more solid than that.

John W. did have an example of a correlation study for K-Ar and Rb-Sr dating in precambrian rocks. The correlation was not very good. I assume he would have mentioned if any others had been done. Maybe since then?

What we really need is the raw data on how these dates correlate, especially on the geologic column of Cambrian and above. We need to see the data to know if there is really any need to explain anything away. Many anomalies never get published, according to John Woodmorappe's references; other quotes indicate that the various methods typically disagree with each other.

There appears to be an increase in K/Ar ages with depth, but there are a number of explanations for that.

A friend related one example of serious anomalies in K/Ar dating that has been reported and that also indicates that there are serious problems.

A few years ago I took a course in the "Evolution of Desert Environments". We were standing on the Simi Volcanic flow, about 80 miles south of the south end of Death Valley. The instructor was a well known geologist and evolutionist from Cal. State Long Beach. He told us that the upper end of the flow was dated at 100,000 years, the middle of the flow was dated at 50,000 years, and the toe of the flow was dated at 20,000 years. He then noted that the whole flow probably occured and solidified (the surface at least) within weeks. He then said, based on his observation of the rates of evolution of desert environments he thought the flow was less than 10,000 years of age. He then said "radiometric dating is the cornerstone of modern historical geology and we get this kind of variation?" Clearly he was not happy with the published dates on the Simi flow.

He was also not happy with the published dates on the flows in the Nevada Atomic Bomb Test site where one of the volcanic flows showed a reversal of isotope ratios and gave a value of 20,000 years in the future! These data were, in fact, published in Science magazine in about November of 1988. Please note, these were not MY ideas but the statements of a convinced, tenured, evolutionary geologist who apparently really wanted to beleive in the credibility of radiometric dating. I am just reporting what HE said!

Thus, there apparently ARE some problems in that kind of radiometric dating.

General unreliability of radiometric dating
The main point at issue is fractionation and its relationship to U/Pb and Th/Pb dating. Jon Covey cited some references about this, and it will take a lot of work to understand what is going on from a creationist viewpoint. But this is another factor that could be causing trouble for radiometric dating. If there is a proof that this could not be so, then I have missed it. I would not want to use a scale that might be right and might be wrong. This looks like the situation with U/Pb and Th/Pb dating so far. Another issue is selective reporting, and also an uncertainty as to how often U/Pb and Th/Pb dates agree with the expected ages of their geologic periods. And I'm curious to see how discordia relate to the possibility of fractionation -- I did look into them at one time. But this point is sufficiently complicated that I can't see the implications right away. In general, when an area is so complicated that I can just barely understand it, then there may be problems with the area that are more complicated still. But my inclination is to think that the same kinds of mixing processes that produce isochrons can also produce discordia.
Furthermore, if there are special circumstances that invalidate the method, then this raises questions about the method in general. It's been an eye opener to me to see all the processes that lead to segregation of different minerals in the magma. We have gold appearing pure at times, silver pure at times, etc., and no one says this is due to radiometric decay. The geological processes at work have a tremendous ability to separate different kinds of elements and minerals. And yet we expect that uranium-lead ratios are determined by radiometeric decay alone (or at least sometimes)!

There are so many complicated phenomena to consider like this that it calls the whole radiometric dating scheme into question.

We haven't even considered the fact that uranium is highly water soluble and lead is not, which could make the dates too old, too. Another factor to consider.

We now have so many things that can make radiometric dating go wrong, and isochrons don't remedy the situation at all, that I think the weight of evidence of radiometric dating is nullified.

I really feel ``bullish'' about the creationist model now. Evolution has always been in trouble. I now have a good explanation for where the flood water came from and where it went, based on water trapped inside the crust (however the planet formed or was created). And now radiometric dating has had its foundation removed from under it. I suspect that a number of geologists now realize the implications of what they know about the lead and uranium content of subducted oceanic plate versus crustal material and the mechanics of magma solidification. What it means is that radiometric dates have no necessary relation to true ages! (For this I'm mainly concerned with the geologic column of Cambrian and above.) At least, there are so many variables to consider that the relationship between radiometric ages and true ages is too complicated to disentangle at present, isochrons or no isochrons.

We have seen many ways in which radiometric dates can be affected by what is going on in the magma. I think this is really the weak spot of radiometric dating. It takes a long time to get to the bottom of things, and I think we have finally hit it.

Still, the creationist task is not finished by proposing all of these mechanisms for invalidating radiometric dating. We can explain many dates away, but a question creationists need to face is which is the best explanation of the data. Can we find evidence that shows that an explanation of radiometric dates in terms of a young geologic column is more plausible than an explanation in terms of an old geologic column? I'm not speaking of evidences based on erosion or the lack of it, or other kinds of evidence, but rather on evidences relating to the radiometric dates and the concenrations of isotopes themselves.

More science problems for "bird evolution".!

Bird Evolution Story Crash-Lands
BY BRIAN THOMAS, M.S. * | MONDAY, NOVEMBER 06, 2017

A new discovery forced a rewrite of bird evolution. Chinese fossil discoveries ballooned the number of birds found among dinosaur-containing rocks. Until now, the oldest Chinese fossil birds, found in Lower Cretaceous deposits, had unique anatomies that seemed better suited for climbing or occasional gliding than for powered flight like most modern birds.1 However, Upper Cretaceous deposits have long revealed modern-looking bird anatomies. The supposed time difference between Lower and Upper layers permitted around 40 million years for modern bird anatomy to evolve. But it only takes one good fact to shoot a bad story out of the sky.


This new find, the Lower Cretaceous Enantiornithine bird fossil named Pterygornis dapingfangensis, had fully fused arm bones that formed the same rigid type of wings that today’s birds use for powered flight. It also had fused pelvic bones like modern birds. Steve Brusatte of the University of Edinburgh reviewed the report and told the BBC, “These are fundamental features of the modern bird blueprint, and are integral to giving birds the strength and rigidity needed to fly.”2

They may have been rare, but this newfound fossil proves that fully formed flyers lived and died among those swamp plants and animals entombed in Lower Cretaceous sediments. Will evolution’s defenders continue to assert that these supposedly oldest birds—with their unique anatomies—evolved into the Upper Cretaceous (and modern bird) anatomy now that we know the modern bird anatomical setup was there all along?

This find fulfills a creation-based prediction. Back in 2009, Creation researcher Mike Oard summarized several fossil discoveries that expanded evolutionary time frames for key transitions, similar to the supposed transition to modern bird anatomy. After summarizing evolutionary rewrites of the first instances of internal fertilization inferred from fossils and human art inferred from archaeology, Oard wrote, “The trend should continue, which would more and more support creation and go against evolution. It is consistent with the original creation of each kind but with a certain inbuilt variety, just as stated in Genesis 1.”3

Oard found more fossils the following year. He summarized over a dozen examples in the Journal of Creation that expand the time ranges for supposed evolutionary innovations.4 Evolutionists claimed that Tiktaalik is an evolutionary transition between fish and amphibians, but the discovery of fully formed amphibian trackways in layers deposited before Tiktaalik debunk this iconic fossil. Another article listed seven more fossil discoveries that stretch evolutionary time beyond credibility.5 Now, this surprisingly early occurrence of modern flying bird anatomy joins the long list.


Mike Oard was right. The trend continues with this modern bird anatomy found so far out of its evolutionary place. Each rewrite reveals the weakness of speculative evolutionary stories and highlights how well Genesis creation and the Flood fit the fossil record. If God created every basic bird kind in the beginning, then we shouldn’t be surprised when they appear fully formed among various other fossils.

References

Thomas, B. 2017. Actual Feathers on Mystery Fossil Indicate ‘Bird.’ Acts & Facts. 46 (5): 15.
Briggs, H. New evidence on how birds took to the air. BBC News. Posted on bbc.com October 10, 2017, accessed October 10, 2017.
Oard, M. J. 2009. Evolutionary fossil-time ranges continue to expand. Journal of Creation. 23 (3): 14-15.
Oard, M. J. 2010. Further expansion of evolutionary fossil time ranges. Journal of Creation. 24 (3): 5-7.
Oard, M. J. 2014. Fossil time ranges continue to be increased. Journal of Creation. 28 (3): 3-4.

Do you all remember when....

When Obama took office- the dems all cried that we should have greater respect for our president and that their children and wives should be untouched?

How quickly they forget what they consider to be proper manners and ways to behave!!!!!

Best of 2017: Sixth Extinction


BY BRIAN THOMAS, M.S. * | TUESDAY, JANUARY 02, 2018

Geologists reassessed the abundance of fossils in Earth’s uppermost rock layers this year, and they believe they found a remarkable sixth global extinction event.1 Their discovery has two significant implications.

When a variety of fossilized life forms found in one rock layer no longer occur in rock layers above, evolutionary scientists call that change in fossil type an extinction event. This assumes that eons separate the layers. And it assumes the creatures were evolving.

For decades, fossil experts recognized only five major extinctions. However, more extensive and accurate fossil counts from around the world, recorded in an online database, revealed creature cut-offs in upper, Cenozoic layers that researchers now interpret as a sixth worldwide mass die-off.

What should this mean to the scientific community at large? It implies that sometimes even the basics of a discipline, like the long-held five extinctions of paleontology, fall short.

The Flood’s liquid violence accounts for sudden animal and plant burial, and its worldwide extent as specified in Scripture explains the worldwide extent of the supposed extinctions. Tweet: The Flood’s liquid violence accounts for sudden animal and plant burial, and its worldwide extent as specified in Scripture explains the worldwide extent of the supposed extinctions.


This revelation also bears significance for Flood geology. Instead of representing extinction events separated by millions of years, Flood geologists interpret all the places where fossil types change rather abruptly as water-borne phases of Noah’s Flood year. The Flood’s liquid violence accounts for sudden animal and plant burial, and its worldwide extent as specified in Scripture explains the worldwide extent of the supposed extinctions. Also, the Flood’s relatively recent occurrence explains why so many of those buried bones still retain original organics inside the long-buried creatures.2

This new wide angle fossil analysis suggests that Cenozoic rocks may contain fossils from the Flood, too.

There weren’t five separate extinctions, or even this sixth one in Earth’s upper rock layers. Just one Flood accounts for all these mass die-offs, in huge, rapid, muddy sequences, as befits the Bible’s brief but precise description.3

Just one Flood accounts for all these mass die-offs, in huge, rapid, muddy sequences, as befits the Bible’s brief but precise description. Tweet: Just one Flood accounts for all these mass die-offs, in huge, rapid, muddy sequences, as befits the Bible’s brief but precise description.



Whether interpreting rocks from a secular or biblical perspective, new (and more accurate) data can and should reshape old ideas.

References

Pimiento, C. et al. 2017. The Pliocene marine megafauna extinction and its impact on functional diversity. Nature Ecology & Evolution. 1: 1100-1106.
Thomas, B. 2017. Best of 2017: Fleshy Fossils. Creation Science Update. Posted on ICR.org December 28, 2017.
Genesis 7:22: “All in whose nostrils was the breath of the spirit of life, all that was on the dry land, died.”

Epigenetic Study Produces 'Backwards' Human-Ape Tree


BY JEFFREY P. TOMKINS, PH.D. * | FRIDAY, AUGUST 16, 2013

* Dr. Tomkins is Research Associate at the Institute for Creation Research and received his Ph.D. in Genetics from Clemson University

A recently published study in the epigenetic modification of DNA regions similar among humans and three different apes not only provided a completely mixed up picture of evolution, but one that was entirely backwards.1

Epigenetic modifications are chemical tags that are added along chromosomes in specific patterns that control how genes are expressed. At present, 12 different types of gene regulating modifications (i.e., chemical tagging) to histone proteins that package the DNA molecule are well-documented in the human genome.2 In addition to the modification of histones, the DNA molecule itself can be tagged by methyl groups on the cytosine nucleotide bases. Thus, the combinatorial epigenetic code is exceedingly complex, but key to understanding how the genome works.

While the DNA code is closely similar in all cells throughout the human body, the epigenetic code and its patterns vary depending on cell and tissue type.2 Because these epigenetic patterns control how genes are expressed in the cell, evolutionists have been interested in comparing the patterns between humans and apes to check for commonalities and dissimilarities. Interestingly, a comparative epigenetic study just published by evolutionary scientists completely contradicts the standard, inferred evolutionary tree for human-ape evolution.

In this study, researchers examined the DNA methylation patterns in the blood cells of humans, chimpanzees, gorillas, and orangutans.1 They focused on the areas of chromosomes 21 and 22 that are highly similar among all four human and ape genomes. The regions between the chromosomes that were too dissimilar (>98.8 percent identical) were not compared. Another recent study has shown that overall, chimp chromosomes 21 and 22 are on average 76.2 and 77.9 percent similar, respectively, in their actual DNA sequence compared to human.3 Thus, there are areas on these chromosomes that are very similar and other regions that are not. Comparative epigenetics, like many other types of evolutionary DNA studies, can only be done on the areas between chromosomes that are highly similar.

In the study, 16 different regions were identified that exhibited strong DNA methylation pattern differences between humans and chimps. These regions were then chosen for further comparison with gorillas and orangutans. The regions were also highly different between humans and the other apes, but not in the levels and patterns one might anticipate based on evolutionary predictions.

When the researchers used the DNA methylation data from the 16 different regions to form an evolutionary tree, it was completely backwards compared to the commonly believed order of evolution for apes that supposedly led up to humans. (See Figure below.) Orangutans, who supposedly are the least evolved among apes compared to humans, actually had more DNA methylation patterns similar to humans than chimps or gorillas. And if that was not enough, gorillas were the next closest in similarity to humans with chimps falling out last! According to evolutionary predictions, chimps should have been most similar to humans, then gorillas, and lastly orangutans.





Major differences between human and chimp epigenetic profiles have been noted before.4 But these study results are particularly interesting because they utterly defy all predictions in the evolutionary paradigm—literally turning it on its head and showing that it is a fallible model of human origins.

These results continue to verify the biblical account of creation wherein all forms of life—including humans, chimps, gorillas, and orangutans—were each created after their kind, uniquely and independently.

References

Fukuda, et al. 2013. Regional DNA methylation differences between humans and chimpanzees are associated with genetic changes, transcriptional divergence and disease genes. Journal of Human Genetics. 58 (7): 446–454.
The ENCODE Project Consortium. 2012. An integrated encyclopedia of DNA elements in the human genome. Nature. 489 (7414): 57-74.
Tomkins, J. 2013. Comprehensive Analysis of Chimpanzee and Human Chromosomes Reveals Average DNA Similarity of 70%. Answers Research Journal. 6 (1): 63–69.
Tomkins, J. 2013. Epigenetics Proves Humans and Chimps Are Different. Acts & Facts. 42 (1): 11-12.

More Fluctuations Found in Isotopic Clocks


BY BRIAN THOMAS, M.S. * | FRIDAY, AUGUST 17, 2012

Age-dating a rock using its radioactive isotopes only works by assuming that the rate at which that "clock" ticks was constant in the past and essentially identical to that in the present. Not long ago, scientists discovered excess helium in crystals1 and "orphaned" polonium radiohalos,2 both of which imply that the decay rates of isotopes commonly used to date earth rocks were dramatically accelerated in the past. Even today, researchers are finding small but significant changes in isotope decay rates, and these add credibility to the idea that isotopic processes were once very different from today's processes.

One standard isotopic clock system uses decaying uranium isotopes. Uranium spontaneously and slowly decays to lead (Pb on the Periodic Table of Elements). Two different uranium isotopes, 235U and 238U, decay into lead at different rates. Geologists assume that the ratio between these is constant and known, giving a convenient shortcut to uranium dating, which only requires that the two uranium amounts be measured.

Of course, this shortcut age-dating method assumes that 238U and 235U have decayed at today's rates throughout the past. It also assumes that the relative amounts of the two have been constant. Physics Today editor Johanna Miller recently wrote, "Standard Pb-Pb dating protocol uses a 238U/235U ratio of 137.88 with zero uncertainty. But several recent studies have cast doubt on that number."3

Miller cited one experiment that found that the uranium ratio (the heavier 238U to lighter weight 235U) is not constant. The study authors wrote, "Our observations have a direct impact on the U-series and U-Th-Pb chronometers," meaning that dates "determined" by uranium decay will need revision.4

Yet another study reported natural variation in the uranium ratio. These authors suggested that natural processes separate the isotopes from one another and skew the ratio, thereby skewing the ages gained by the assumption that the ratio was constant. These authors wrote, "The discovery that 238U/235U varies in nature also has implications for the precision and accuracy of U-Pb dating. The total observed range in U isotope compositions would produce variations in 207Pb/206Pb ages of young U-bearing minerals of up to 3 Ma , and up to 2 Ma for minerals that are 3 billion years old."5

Two to three million years are not a huge part of three billion. So, adjusting already-published dates to reflect these new and larger error margins will not displace billion-year-old age assignments. However, if today's comparatively tame natural processes affect isotope ratios, then ancient and much more violent processes could have affected those ratios and rates much more, just as the helium in crystals and orphaned radiohalos imply.

Another isotope system used for dating, though more rarely than uranium, is that which occurs when a radioactive samarium isotope decays to the element neodymium. A 2012 Science report re-measured samarium's decay rate, finding that it occurs only about 66 percent as fast as "the currently used value" for age dating.6 This is a huge discrepancy! It means that all published samarium-dated rock ages need to be re-evaluated.

In addition, Purdue University just applied for a patent on a solar flare warning system that relies on ways in which the earth-sun relationship somehow alters nuclear decay rates. Purdue News reports that "Advance warning could allow satellite and power grid operators to take steps to minimize impact and astronauts to shield themselves from potentially lethal radiation emitted during solar storms."7 Their invention would rely on detecting changes in the rate of manganese 54 decaying to chromium 54. Researchers observed the decay rate changes occurring about a day prior to solar flares.

Even carbon dating is in hot water. Scientists typically use this method to age-date carbon-containing objects thought to be only tens of thousands of years old. The relevant radioactive carbon isotope (14C) decays so fast that it should no longer exist in earth materials that are a million or more years old.8 Recently, researchers measured elevated levels of 14C in correlated tree rings and attributed the spike to an unidentified "massive cosmic event."9 If natural processes did alter carbon isotope ratios, then why trust dates that assume the ratios were never altered?

Science shows that isotopic clocks are not all trustworthy.10 The isotope ratios and rates upon which they depend are variable, even on today's comparatively calm earth surface. During the tumultuous Flood, when immeasurable quantities of mantle material were ejected onto earth's surface and water potentially contaminated everything, isotopic clocks ticked much, much faster.11

References

Humphreys, D.R. 2005. Young Helium Diffusion Age of Zircons Supports Accelerated Nuclear Decay. In Radioisotopes and the Age of the Earth: Results of a Young-Earth Creationist Research Initiative, Vol. 2. Vardiman, L. et al., eds. El Cajon, CA: Institute for Creation Research and Chino Valley, AZ: Creation Research Society.
Gentry, R.V. 1974. Radiohalos in a Radiochronological and Cosmolocial Perspective. Science. 184 (4132): 62-66.
Miller, J. 2012. Time to reset isotopic clocks? Physics Today. 65 (6): 20-21.
Stirling, C.H. et al. 2007. Low-temperature isotopic fractionation of uranium. Earth and Planetary Science Letters. 264 (1): 208-225.
Weyer, S. et al. 2008. Natural fractionation of 238U/235U. Geochimica et Cosmochimica Acta. 72 (2): 345-359.
Kinoshita, N. et al. 2012. A Shorter 146Sm Half-Life Measured and Implications for 146Sm-142Nd Chronology in the Solar System. Science. 335 (6076): 1614-1617.
Venere, E. New system could predict solar flares, give advance warning. Purdue News. Posted on purdue.edu, August 13, 2012.
Despite this, 90 instances of C-14 in supposedly million-year-old earth materials were reviewed and 10 more were presented in Baumgardner, J.R. et al. 2003. Measurable 14C in Fossilized Organic Materials: Confirming the Young Earth Creation-Flood Model. In Proceedings of the Fifth International Conference on Creationism. R.L. Ivey, ed. Pittsburgh, PA: Creation Science Fellowship, Inc., 127-142.
Lovett, R. A. Mysterious radiation burst recorded in tree rings. Nature news. Posted on nature.com June 3, 2012, accessed August 10, 2012.
Austin, S.A. 2005. Do Radioisotope Clocks Need Repair? Testing the Assumptions of Isochron Dating Using K-Ar, Rb-Sr, Sm-Nd, and Pb-Pb Isotopes. In Radioisotopes and the Age of the Earth: Results of a Young-Earth Creationist Research Initiative, Vol. 2.Vardiman, L.et al., eds. El Cajon, CA: Institute for Creation Research and Chino Valley, AZ: Creation Research Society.
When heated to plasma, bare nuclei of rhenium radioisotopes decay a billion times faster than normal. See Bosch, F. et al. 1996. Observation of Bound-State β- Decay of Fully Ionized 187Re: 187Re- 187Os Cosmochronometry. Physical Review Letters. 77 (26): 5190-5193.

Cherry-Picked Age for Key Evolutionary Fossil


BY BRIAN THOMAS, M.S. * | THURSDAY, JUNE 08, 2017

Homo naledi, the latest failed candidate for a missing link in human evolution, was deposited in the Rising Star cave system in South Africa. New fossil dating attempts reveal troubling difficulties with science’s attempt at answering historical questions.

The answer to naledi’s timing carries some big implications. If the naledi fossils receive a date of three or so million years, then they could remain in the running for a possible missing link between ancient apes and modern humans. But researchers gave the remains a much more recent age, unseating naledi from any evolutionary hopes. How did they determine an age for the remains or the flowstones discovered around them? After all, it’s not like time is a substance that science can directly probe.

Paul Dirks from Australia’s James Cook University led the study, published in the online technical journal eLife.1 Dirks told LSU’s Media Center, “The dating of naledi was extremely challenging. Eventually, six independent dating methods allowed us to constrain the age of this population of Homo naledi to a period known as the late Middle Pleistocene.”2

Why six methods? If scientists really trust any single method, shouldn’t that one suffice? The need to compare so many different methods on various samples is just the first of many difficulties with scientific attempts to assign ancient dates to objects.

Results from five of those six methods provide enough information to understand the challenge this team faced in assigning an evolutionary-friendly age to these potentially key fossils. They applied radiocarbon (C-14), Electron-Spin Resonance (ESR), uranium-thorium decay (U-Th), and Optically-Stimulated Luminescence (OSL) in a central age statistical model (CAM), and OSL in a minimal age model (MAM) to bones, teeth, and cave flowstones that surrounded the fossils.

Dating methods should reveal their reliability by independently giving very similar ages for the same sample and its surroundings. But these six results landed all over the place, leaving an 800,000 year gap between the youngest and oldest dates.

U-Th on the flowstone FS1b showed an age of about 290,000 uranium years, but OSL (CAM) results ranged from 546,000 to 560,000 years. OSL (MAM) on flowstone FS1a showed 353,000 years, but OSL (CAM) gave approximately 849,000!1 Will the real flowstone age please stand up?

ESR results from one tooth ranged from 87,000 to 104,000 years, but the U-Th method on the same sample showed only 43,500 to 46,100 years. Similarly, ESR from another tooth yielded 230,000 to 284,000, whereas U-Th results for the same sample ranged 66,200 to 146,800 years. Last, C-14 results for associated bones ranged from 33,000 to about 35,500 carbon years.

How did Dirks’ team determine that the H. naledi bones were deposited between 236,000 to 335,000 years from this wide-ranging age collection?

Actually, discordant age-dates like these typify attempts to use natural processes like decaying radioactive elements or erosion as clocks. Very often, researchers can select from a range of options.3 And when they do, they commonly explain away those results they choose to reject.4 That’s not science; it’s cherry picking. It’s more like blind guesswork with evolutionary time driving date selection—they look at all the data and essentially select the ones that fit what they are looking for. This Homo naledi paper was no exception.

The naledi dating team chose the older tooth results, from ESR, and the U-Th ages from certain flowstones. They did not even explain why they rejected the U-Th result from three different Homo naledi teeth, which ranged from 43,500 to 146,000 years.

The team also rejected all the data taken directly from the actual bones they were trying to date. At least they offered some reasoning when they cited contamination from calcite precipitation as affecting the C-14 results. But what direct observation of contamination led them to this speculation? They gave none.

Without a truly objective way to select from their options, a strong possibility emerges—perhaps none come anywhere close to the fossil’s actual age.

In the end, it looks like these researchers rejected all the younger ages in favor of the oldest results. But the new age determination still lands nowhere near the three million years that Homo naledi needs to satisfy the evolutionary model. But at least an age of 236,000 to 335,000 years doesn’t sound too embarrassing for evolution—they’re only off by a factor of ten.5

References

Dirks, P.H.G.M. et al. 2017. The age of Homo naledi and associated sediments in the Rising Star Cave, South Africa. eLife. 6:e24231.
New Research Shows Early Ancestor May Have Coincided with Modern Humans. LSU Media Center. Posted on lsu.edu May 9, 2017, accessed May 26, 2017.
Woodmorappe, J. 1979. Radiometric Geochronology Reappraised. Creation Research Society Quarterly. 16 (2): 102-129.
Woodmorappe, J. 1999. The Mythology of Modern Dating Methods. Santee, CA: Institute for Creation Research.
Anatomically modern human remains already occur in Middle Pleistocene sediments, which in a biblical timeline were deposited during the post-Flood Ice Age, showing that naledi did not predate, and thus did not evolve into, modern man.

Are Evolution and Adaptation the Same?


BY JEFFREY P. TOMKINS, PH.D. * | MONDAY, APRIL 30, 2018

Due to the bombardment of evolutionary propaganda, most people think the terms evolution and adaptation basically represent the same thing. But nothing could be further from the truth. When one has a proper understanding of how creatures adapt and the incredible complexity of the mechanisms that enable them to do so, logic points to an all-wise Creator as adaptability’s cause.1,2 The scientific reality of the engineered complexity of adaptation is actually contradictory to the man-made myth of step-by-step gradual evolution over time.

The scientific reality of the engineered complexity of adaptation is actually contradictory to the man-made myth of step-by-step gradual evolution over time.

Adaptability is a fundamental feature of all living things on Earth. The problem is that evolutionists find it difficult to explain how intricate adaptive mechanisms could have emerged. A plant or animal cannot adapt unless it is already adaptable. As the saying goes, in their quest to explain the survival of the fittest, evolutionists have no viable explanation for the arrival of the fittest. Living organisms appear to be innately adaptable, thus the complexity and importance of adaptability are actually a key argument in debunking evolution.

Evolutionists believe adaptable traits arose through the progressive accumulation of random genetic mutations that somehow provided an advantage to living things facing specific environmental challenges. But not only are nearly all mutations either harmful or at best neutral, it’s impossible to achieve a functioning system of many orchestrated components one step at a time. All-or-nothing systems cannot evolve bit by bit. For virtually any complex system to work, every component has to be in place all at once!

Mechanisms of adaptation are made up of complex integrated components, including environmental sensors, signaling pathways, feedback and feed-forward loops, and information control systems in the creature’s DNA. By applying basic engineering principles to these living systems, the conclusion is obvious that they were intelligently designed by God.3

Another feature of adaptability that often gets confused with evolution is the genetic variability built into different kinds of creatures.4 For example, because of human breeding efforts based on the created genetic variability built into the canine kind, various dog breeds have been produced that look radically different from each other. But the fact remains they are all dogs and haven’t been changed into a fundamentally different creature like a cat. Even the Galapagos finches that Charles Darwin and others have studied could interbreed with each other, and they produced nothing but finches. Evolutionists like to extrapolate the observed variability within kinds as evidence for single cells evolving into people, but built-in mechanisms of genetic variability are an important part of adaptable design, too.

The facts of science clearly point to the wonderful engineering of an all-powerful Creator. Tweet: The facts of science clearly point to the wonderful engineering of an all-powerful Creator.

Evolution and adaptation are not the same. The complex internal mechanisms of adaptation combined with built-in genetic variability allow creatures to fill niches, diversify, and make homes across many different environments. The facts of science clearly point to the wonderful engineering of an all-powerful Creator, not the failed myth that nature somehow created itself through chance random processes.

References

Guliuzza, R. J. 2017. Engineered Adaptability: Engineering Principles Point to God’s Workmanship. Acts & Facts. 46 (6): 16-19.
Guliuzza, R. J. 2017. Engineered Adaptability: Arriving at a Design-Based Framework for Adaptability. Acts & Facts. 46 (8): 17-19.
Guliuzza, R. J. 2017. Engineered Adaptability: Engineering Principles Should Guide Biological Research. Acts & Facts. 46 (7): 17-19.
Tomkins, J. P. 2012. Mechanisms of Adaptation in Biology: Genetic Diversity. Acts & Facts. 41 (5): 8.

Homo naledi Bones Not Ritually Buried

BY TIM CLAREY, PH.D. * | THURSDAY, MAY 17, 2018

Since Lee Berger and his team announced their discovery of Homo naledi,1 they have been claiming that the bones found in the Dinaledi Chamber, South Africa, were deliberately disposed by living Homo naledi.2 While some objected to this interpretation,3-5 Berger’s team stuck with it and continued to promulgate the human-like behavior associated with purposeful burial.6

Homo naledi was an ape—evidence from all sides points to this. Tweet: Homo naledi was an ape—evidence from all sides points to this.


A new study published in PNAS strikes another blow against the deliberate disposal interpretation.7 Charles Egeland at the University of North Carolina at Greensboro and his colleagues from across the globe used machine-learning technology to reassess the Homo naledi discovery site and another cave site in Spain called Sima de los Huesos.

The authors explained their methods:

Here we employ a machine-learning approach that compares hominin skeletal part representation in the SH and DC assemblages to 14 modern and prehistoric accumulations of modern human, archaic human, australopith, and nonhuman primate skeletal remains.7

In other words, the scientists “taught” their computer program to recognize patterns by studying known sites of hominin accumulations. Then, the scientists turned their computer program on the Dinaledi Chamber (DC) and the Sima de los Huesos (SH) site, two deep-cave locations containing multiple hominin remains.

The results were consistent and noteworthy. They reported,

In all of the models except for the neural network (NN) , the most likely classification of the SH and DC is in the group that includes the modern cave baboons and scavenged modern human corpses.7

Egeland and his colleagues added, “As to the DC assemblage, skeletal part data suggest that, similar to the situation at the SH, hominin corpses did not arrive in the chamber as complete skeletons and/or experienced some postdepositional disturbance.”7

Finally, the scientists acknowledged “that the results presented here do not refute outright a hominin origin for the SH and DC assemblages, but we do contend that the data also support partially or completely nonanthropogenic formational histories.”7

Nevertheless, the recurrent clustering of the DC assemblage with the disturbed and carnivore-consumed samples and, in particular, the naturally accumulated bone sample of cave baboons, is intriguing.7

These conclusions match the available bone studies done recently by O’Micks that suggest Homo naledi was nothing more than an ape, similar to the australopith Lucy.8-10 And these results fit the interpretation by Clarey that the bones of Homo naledi were most likely washed in during Ice Age flooding of the Rising Star Cave system, which includes the famous Dinaledi Chamber.5

Apes, like Homo naledi, were merely one of the animal kinds created along with humans on Day 6 of Creation Week. Tweet: Apes, like Homo naledi, were merely one of the animal kinds created along with humans on Day 6 of Creation Week.


Homo naledi was an ape—evidence from all sides points to this. And the bones in the Dinaledi Chamber and other chambers in the cave system represent assemblages of apes caught in the wrong place at the wrong time. Only humans were created in the image of God. Apes, like Homo naledi, were merely one of the animal kinds created along with humans on Day 6 of Creation Week.


References

Berger, L. R. et al. 2015. Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa. eLife. 4: e09560: 1-35. DOI: 10.7554/eLife.09560.
Dirks, P. H. G. M. et al. 2015. Geological and taphonomic context for the new hominin species Homo naledi from the Dinaledi Chamber, South Africa. eLife. 4: e09561:1-37. DOI: 10.7554/eLife.09561.
Val, A. 2016. Deliberate body disposal by hominins in the Dinaledi Chamber, Cradle of Humankind, South Africa? Journal of Human Evolution. 96: 145-148.
Thackeray, J. F. 2016. The possibility of lichen growth on bones of Homo naledi: were they exposed to light? South African Journal of Science. 112 (7/8): 1-5.
Clarey, T. L. 2017. Disposal of Homo naledi in a possible deathtrap or mass mortality scenario. Journal of Creation. 31(2): 61-70.
Dirks, P. H. G. M. et al. 2016. Comment on “Deliberate body disposal by hominins in the Dinaledi Chamber, Cradle of Humankind, South Africa?” Journal of Human Evolution. 96: 145-153.
Egeland, C. P. et al. 2018. Hominin skeletal part abundances and claims of deliberate disposal of corpses in the Middle Pleistocene. PNAS. 115 (18): 4601-4606. DOI.org/10.1073/pnas.1718678115.
O'Micks, J. 2016. Homo naledi Probably Not Part of the Human Holobaramin Based on Baraminic Re-Analysis Including Postcranial Evidence. Answers Research Journal. 9: 263-272.
O'Micks, J. 2017. Further Evidence That Homo naledi Is Not a Member of the Human Holobaramin Based on Measurements of Vertebrae and Ribs. Answers Research Journal. 10: 103-113.
O'Micks, J. 2017. Likely Discontinuity Between Humans and Non-Human Hominins Based on Endocranial Volume and Body Mass with a Special Focus on Homo naledi—A Short Analysis. Answers Research Journal. 10: 241-243.


So upon further research the evidence points to baboons scavenging human remains and dragging them into their cave- thus the reason we have simian and human bones!

a response to rampartb.

Sorry for the delay and making a different thread. If you are like me if I don't get a response in a few days I remove a thread.

As for homologous features in embryos: Remember this just because something appears similar or even near identical means little. Most of the time the homologous feature is widely genetically different. So similar appearance means nothing.

You said (I paraphrase) given enough time anything can happen.

Well let us look at the big picture of evolutionary hypotheses and the facts they declare. They are not in any specific order and I will keep them to just velociraptor to bird.

1. Evolution is declared to have occured due to random mutations adding greater complexity and new information to a genome and thus over eons of time various kingdom, phyla, order. family, genera and species formed.

2. Natural Selection acted upon the "good" mutations that supposedly gave the mutated creature an advantage over its predecessors in that ecological niche and thus allowed it to flourish until the next "positive" mutation, etc.etc.

So let us look at the real world of going from a velociraptor (reptile dinosaur) to an avian . All these things had to have happened via mutation and give the "intermediary" an advantage in its ecological niche.

1. The biggest is scale to feather! This in and of itself is no small feat! Scales are used by cold blooded animals in that they allow the reptile to absorb heat from teh surface.

Feathers are on warm blooded animals and are used to keep heat from escaping to quickly (insulation)

2. Scales are surface fixed plates while feathers grow sub dermal or under the skin!

A feather:
?1522293688

So evolution would need to shed an externally attached plate, form a follicle and evolve the varied parts of the feather.

While it is doing that- what happens to the metabolism? If it is still cold blooded- it would die, if it turns warm blooded before the feathers full form- it dies.

3. Next you have to evolve from a mouth to a beak! Lose the skin- lose the teeth (archy excepted) and develop keratin to cover the beak instead of flesh.

4. You have to atrophy the lower limbs to accommodate more hopping than speed running. and increase the forelimbs to be able to develop wings for flight!

5. The raptor also needs to evolve an "oil" gland at the base of the tail. all birds "preen" and this preening involves drawing oil from the gland to clean and lubricate the feathers. If this isn't evolved and functioning when the raptor to bird has its feathers- the feathers will rot!

6. You have to rewrite instincts so that it will preen. this also involves changing its neck muscles so it can reach all its body with its beak (mouth won't work) so it can clean and lube its feathers.

7. Its skeletal structure has to change to streamline it for flight.

8. Its lungs have to change for though birds have lungs like all animals- it breathes differently than land animals.
Bird lungs could not work on land animals and land animal lungs would not work for birds in flight.

9. You also have to dump the tail for tail feathers (archy excepted)

10. The flesh has to change as reptile flesh is genetically different from bird flesh.

11. Have to rewrite instincts to get the intermediaries to fly instead of run.

Finally. Of all the few remaining feathered dinos. not debunked by paleontologists and ornithologists, all of the remaining feathered dinos appear in the geologic record--AFTER true birds already appeared by millions of years. They therefore cannot be intermediaries!

Lastly- Mutations are known to be over 99.9% slightly to very harmful to the host. There has yet to be demonstrated a true "positive" mutation that added greater complexity or new information to a genome.

Very few mutations actually make it into the genome to where it rewrites the DNA so the mutation can reproduce in the species- it has to overwhelm several layers of defense within the cell to actually be able to stay !

If one wishes to argue in very fast evolution- then we get to punctuated equilibria which is almost completely discredited now- or a variant of Goldschmidts hopeful monster theory ( a reptile lays an egg and a bird hatches.)

We know empirically this cannot happen- that is too much mutation at once and that has been shown to be 100% fatal to every known species.

On paper to one taught to believe in evolution- it all seems so simple, but when you map it out and look at what really has to happen in the real world- it becomes an impossibility.


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