Radiometric dating failures. Radiometric dating

radiometric dating failures

Radiometric Dating Failures Third, many dating methods that don't involve radioisotopes—such as helium diffusion, erosion, magnetic field decay, and original tissue fossils—conflict with radioisotope ages by showing much younger apparent ages. These observations give us confidence that radiometric dating is not trustworthy. When we date rock of known age we test the claims and we see obvious failures. Since the magma has old radiometric dates, Anomalies of radiometric dating. Radiometric Dating Failures. Coffee Bagel Dating App! They also radiometric dating failures pointed out that for the anomalies to be accounted for by excess marriage not dating recap ep 12 argon, unreasonably high partial pressures of Ar during crystallization would have to be required. Third, many dating methods that don't involve radioisotopes—such as helium diffusion, erosion, magnetic field decay, and original tissue fossils—conflict with radioisotope ages by showing much younger apparent ages. These observations give us confidence that radiometric dating is not trustworthy. When we date rock of known age we test the claims and we see obvious failures. Since the magma has old radiometric dates, Anomalies of radiometric dating.


Radiometric Dating Does Work!

If they contained a hundred times more excess argon, their K-Ar ages would be a hundred times greater, I suppose. Radiometric same dating of fractional crystallization would be true of non-granitic melts. We can get more realistic mixings of three sources with the same result by choosing the sources to be linear combinations of sources 1, failures, and 3 above, with more natural concentrations of D, P, and N.

Click on photo for high resolution We know when this dome formed. Radiometric Dating Does Work! Radiometric dating of rocks and minerals using naturally occurring, long-lived radioactive isotopes is troublesome for young-earth creationists because the techniques have provided overwhelming evidence of the antiquity of . 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. A similar problem can occur if the excess argon 40 dissolved within lava or magma is not able to escape, due to rapid cooling or subsequent deposits of sediment or other lava on top.

One can also hypothesize that leaching occurred. See also the articles on this website on the ages of the geologic periods, radiometric dating (Radiometric dating), radiocarbon dating (Radiocarbon dating), time machines (Time machine) and the "uniformitarian" assumption (Uniformitarian). As with other radiometric ‘dating’ methods, the U-Pb and Pb-Pb isochron methods have been questioned in the open literature.

As with other radiometric ‘dating’ methods, the . Carbon dating is based on the assumption that the amount of C14 in the atmosphere has always been the same. But there is more carbon in the atmosphere now than there was 4 thousand years ago. (1) Since carbon dating measures the amount of carbon still in a fossil, then the date given is not accurate.

Radiometric Dating Does Work! Radiometric dating of rocks and minerals using naturally occurring, long-lived radioactive isotopes is troublesome for young-earth creationists because the techniques have provided overwhelming evidence of the antiquity of .

Radiometric Dating

Some of these samples were again crushed drill core, but the majority were crushed percussion drill chips. When their isotopic data were plotted on a U-Pb isochron diagram, six of the nine samples plotted close to the reference Ma isochron, while the other three were widely scattered see Figure In unrelated investigations, Dickson et al.

The technique did in fact work, Pb isotopic traces of the deeply buried No. This mineralisation, 40 m below the surface, is blind to other detection techniques. However, most of the soil samples consisted of detritus eroded from the Middle Proterozoic Kombolgie sandstone, so because the samples from near the mineralisation gave a radiogenic Pb signature Dickson et al.

Snelling 24 has already highlighted a telling omission by Hills and Richards. The standard used to correct the data in Table 6 was the Mt Isa Pb standard with an isotopic composition: Similarly, Cunningham et al.

That Ra mobility at depth in the primary ore zone is currently more significant than U migration has been confirmed by Dickson and Snelling, 15 which of course results ultimately in the redistribution of Pb, the end-member of the whole U decay chain. The Rn gas is known to migrate along fractures and rise through the ground over considerable distances to form a halo in the air above, while Rn is also transported in ground waters.

Thus it is to be expected that the pattern of oxidation of uraninites and dispersion of U should reflect the present-day circulation of ground waters 7 and that present-day ground waters should be carrying U and He. However, both Hills 12 and Snelling 13 have recognised that U and Pb also have migrated several times and on a considerable scale in the primary ore zone, with the latest redistribution having produced supergene uraninites, often with colloform banding, found as fracture and cavity infillings see Figure 16 again , and between quartz and gangue grain boundaries.

The unit cell dimensions of these uraninites, plus this textural evidence, supports the conclusion that these uraninites have precipitated after dissolution of earlier formed uraninite and transportation in low-temperature ground waters.

The weathered whole-rock samples all of course come from Koongarra itself, and consist of secondary ore samples from the weathered schist zone, plus weathered schist samples that contain U dispersed down-slope by ground waters moving through the weathered rock.

For this mixing explanation to be feasible there should be some other evidence of mobilisation of Pb in the area. This near-surface zone is inundated for approximately six months of the year as a result of the high monsoonal rainfall in this tropical area. This means that the top of the weathered schist zone is regularly fluctuating between wet and dry conditions, so that any trace elements such as Pb leached from the weathered ore and transported by ground water in the weathered schist zone would also be dispersed vertically up into the thin surficial sand cover on top of the weathered schist - the sandy soils that were sampled by Dickson et al.

However, not all of Dickson et al. Remember, the schists are supposed to be the product of regional metamorphism at Ma, while the Kombolgie sandstone is regarded as having been deposited around Ma.

Perhaps this difference is a reflection of the extent of mixing in each type of sample at their respective levels in the weathering profile. Nevertheless, what is astounding is that Dickson et al. But since that latter result has no apparent geological meaning, because it also cannot be correlated with any known geological event, nothing then is certain at all from any of these U-Th-Pb isotopic studies of the Koongarra ores, rocks and surrounding soils.

There is clearly a real sequence of rock units that comprise the total geological record, from the so-called Archaean to the Recent, the formation of which needs to be understood and coherently modelled within the biblical framework of a recent Creation and global Flood. Much progress towards this goal has been, and is being, made within the relatively small creationist geological community. The concerns raised by Zheng 1 regarding U-Pb isochrons are warranted.

Dr Andrew Snelling is a geologist with a B. He has worked in the mining industry and is still a consultant geologist in the field and in research projects, but now also works full-time with the Creation Science Foundation where he contributes to Creation Ex Nihilo magazine and edits the Creation Ex Nihilo Technical Journal. He resides in Brisbane, Australia. Get the latest answers emailed to you or sign up for our free print newsletter. Please follow the instructions we emailed you in order to finish subscribing.

Answers in Genesis is an apologetics ministry , dedicated to helping Christians defend their faith and proclaim the gospel of Jesus Christ. Snelling on April 1, Regional geology map showing the location of the Koongarra uranium deposit. Local geology map showing the location of the Koongarra No.

Because of surficial cover the geological units and outline of the mineralisation are projected to the surface from the base of weathering. Simplified cross section through the No. Paragenesis diagram showing the stages of formation and development of the minerals comprising the Koongarra uranium deposit.

Remobilisation and redeposition of uraninite white mineral. Photomicrograph shows uraninite veins left and right partially destroyed by dissolution of uranium which has been redeposited as scattered veinlets and shapeless masses of a new generation of uraninite middle. Uraninite light grey has been dissolved and redeposited as thin veinlets and shapeless masses within a chlorite dark grey matrix which is also replacing the main uraninite grain. Two generations of uraninite grains lighter grey , and more oxidised supergene veins and patches darker grey.

The small scattered white grains are galena. Two generations of uraninite grains white, left of photomicrograph and later thin supergene encrustations mid grey around quartz grains dark grey. The very bright mineral right is galena which has similarly dissolved and redeposited. Remobilised uraninite light grey deposited as scattered grains with a chlorite dark grey matrix.

A remobilised galena vein white-grey cuts across the uraninite-chlorite association. An enlarged view of uraninite dark grey sub-grains within a larger vein.

Galena light grey veinlets which both cross-cut and separate the uraninite sub-grains. The Pb in the galena is supposed to have migrated from the uraninite where it was supposedly produced by radioactive decay. Compositional traverse across a uraninite grain similar to those in Figure In the following article, some of the most common misunderstandings regarding radiocarbon dating are addressed, and corrective, up-to-date scientific creationist thought is provided where appropriate.

The presence of measurable radiocarbon in fossil wood supposedly tens and hundreds of millions of years old has been well-documented. Skip to main content. What About Radioisotope Clocks? But ICR scientists have carefully examined their claims and found flaws and holes The presence of carbon C in specimens that are supposedly millions of years old is a serious problem for believers in an old earth.

A straightforward reading of the Bible describes a 6,year-old Does radioisotope dating prove that the earth is millions of years old? We offered four reasons why radioisotope dating Russell Humphreys reported that helium diffusion from zircons in borehole GT-2 at Fenton Since such isotopes are thought to decay at consistent rates over time, the assumption Three geologists have reported what they called the first "successful" direct dating of dinosaur bone.

Will this new radioisotope dating or radiodating technique solve the problems that plagued older A trio of geologists has published what they called the first successful direct dating of dinosaur bone. They used a new laser technique to measure radioisotopes in the bone, yielding an age of millions Radioactive Isotope Dating Is Fallible.

Radioactive Decay Rates Not Stable. They helped underpin belief in vast ages and Radiocarbon in 'Ancient' Fossil Wood. A Tale of Two Hourglasses. In your kitchen you start a three-minute egg timer and a minute hourglass simultaneously and then leave. You return a short while later to find the hourglass fully discharged but not the egg timer!

Confirmation of Rapid Metamorphism of Rocks. Where thick sequences of sedimentary rock layers have been deposited in large basins, the deepest layers at the bottoms of the sequences may subsequently have become folded by earth movements when subjected The most primitive type of meteorites are called chondrites, because they contain little spheres of olivine crystals known as chondrules.

Because of their importance, meteorites have been extensively dated radiometrically; the vast majority appear to be 4. Some meteorites, because of their mineralogy, can be dated by more than one radiometric dating technique, which provides scientists with a powerful check of the validity of the results. The results from three meteorites are shown in Table 1. Many more, plus a discussion of the different types of meteorites and their origins, can be found in Dalrymple There are 3 important things to know about the ages in Table 1.

The first is that each meteorite was dated by more than one laboratory — Allende by 2 laboratories, Guarena by 2 laboratories, and St Severin by four laboratories. This pretty much eliminates any significant laboratory biases or any major analytical mistakes. The second thing is that some of the results have been repeated using the same technique, which is another check against analytical errors.

The third is that all three meteorites were dated by more than one method — two methods each for Allende and Guarena, and four methods for St Severin. This is extremely powerful verification of the validity of both the theory and practice of radiometric dating. In the case of St Severin, for example, we have 4 different natural clocks actually 5, for the Pb-Pb method involves 2 different radioactive uranium isotopes , each running at a different rate and each using elements that respond to chemical and physical conditions in much different ways.

And yet, they all give the same result to within a few percent. Is this a remarkable coincidence? Scientists have concluded that it is not; it is instead a consequence of the fact that radiometric dating actually works and works quite well. Creationists who wants to dispute the conclusion that primitive meteorites, and therefore the solar system, are about 4. One of the most exciting and important scientific findings in decades was the discovery that a large asteroid, about 10 kilometers diameter, struck the earth at the end of the Cretaceous Period.

The collision threw many tons of debris into the atmosphere and possibly led to the extinction of the dinosaurs and many other life forms. The fallout from this enormous impact, including shocked quartz and high concentrations of the element iridium, has been found in sedimentary rocks at more than locations worldwide at the precise stratigraphic location of the Cretaceous-Tertiary K-T boundary Alvarez and Asaro ; Alvarez We now know that the impact site is located on the Yucatan Peninsula.

Measuring the age of this impact event independently of the stratigraphic evidence is an obvious test for radiometric methods, and a number of scientists in laboratories around the world set to work.

In addition to shocked quartz grains and high concentrations of iridium, the K-T impact produced tektites, which are small glass spherules that form from rock that is instantaneously melted by a large impact. The K-T tektites were ejected into the atmosphere and deposited some distance away. Tektites are easily recognizable and form in no other way, so the discovery of a sedimentary bed the Beloc Formation in Haiti that contained tektites and that, from fossil evidence, coincided with the K-T boundary provided an obvious candidate for dating.

Scientists from the US Geological Survey were the first to obtain radiometric ages for the tektites and laboratories in Berkeley, Stanford, Canada, and France soon followed suit. The results from all of the laboratories were remarkably consistent with the measured ages ranging only from Similar tektites were also found in Mexico, and the Berkeley lab found that they were the same age as the Haiti tektites. The K-T boundary is recorded in numerous sedimentary beds around the world.

Numerous thin beds of volcanic ash occur within these coals just centimeters above the K-T boundary, and some of these ash beds contain minerals that can be dated radiometrically. Since both the ash beds and the tektites occur either at or very near the K-T boundary, as determined by diagnostic fossils, the tektites and the ash beds should be very nearly the same age, and they are Table 2.

There are several important things to note about these results. First, the Cretaceous and Tertiary periods were defined by geologists in the early s. The boundary between these periods the K-T boundary is marked by an abrupt change in fossils found in sedimentary rocks worldwide.

Its exact location in the stratigraphic column at any locality has nothing to do with radiometric dating — it is located by careful study of the fossils and the rocks that contain them, and nothing more.

Furthermore, the dating was done in 6 different laboratories and the materials were collected from 5 different locations in the Western Hemisphere. And yet the results are the same within analytical error. In the early afternoon of August 24, 79 CE, Mt Vesuvius erupted violently, sending hot ash flows speeding down its flanks. These flows buried and destroyed Pompeii and other nearby Roman cities. We know the exact day of this eruption because Pliny the Younger carefully recorded the event.

They separated sanidine crystals from a sample of one of the ash flows. Incremental heating experiments on 12 samples of sanidine yielded 46 data points that resulted in an isochron age of 94 years. The actual age of the flow in was years. Is this just a coincidence? No — it is the result of extremely careful analyses using a technique that works.

Radioactive “Dating” Failure Radiometric dating failures

About the Author s: This will retain dating isochron property, but will make the isochron look too old. 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 failures in the earth. This radiometric interesting because both radium and lead are daughter products of uranium. This technique requires assumptions about lead and uranium loss, and seems to give good evidence of a reliable date relative to decay constantsespecially when there is agreement with other methods such as isochrons on the same system. Carbon Dating...100% accurate right?!

So it must be possible for that excess argon to failures in, even though the crystal is supposed failures exclude it. It may also be that lava is produced by melting the bottom of continents and successively different layers are melted with time, or there could be a radiometric for lighter isotopes to come to the dating of magma chambers, making the lava there appear older. It is, therefore, not surprising that many misconceptions about what radiocarbon can dating cannot do and what it has or has not shown are prevalent among creationists and evolutionists - lay people as well as scientists not directly involved in this field.

I will comment more on this below, but a few comments now are appropriate. The fact that not all of the radiometric is retained would account for smaller amounts of argon near the surface, as I will explain below. This is called the biostratigraphic limit of the flow.

It could decrease them, if they were regarded as flukes.


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 dating 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 online dating maroc 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 radiometric 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 dating 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 radiometric the magma chamber, and lava erupting later would come from lower down. A dating of processes could cause the parent substance to be depleted failures the top radiometric 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: 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 dating stages of the same volcano often extrude lavas exhibiting somewhat different mineral compositions, particularly if an extensive period of time separated the eruptions.

Failures of this type dating them to look into the possibility that a single magma might produce rocks of varying mineral failures. A pioneering investigation into the crystallization of magma was carried out by N.

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. Radiometric the failures process continues, dating 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 dating depleted in iron, magnesium, dating 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. For this reason, this arrangement of minerals became known as Bowen's reaction series.

On the upper left branch dating this reaction series, olivine, the first mineral to form, Ml] react with the remaining melt to become pyroxene. This reaction will continue dating the failures mineral in the series, dating 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 radiometric 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 failures 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 dating feldspar. Although these minerals crystallize radiometric 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 radiometric 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. 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 failures the chamber, failures will form radiometric rock with a chemical composition much different from the original magma Figure 3. In many instances the melt which has migrated from dating initial magma chamber will undergo further segregation. As crystallization progresses failures the " new" magma, the solid particles may accumulate into rocklike masses surrounded by pockets failures 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 failures 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 dating examine some failures these mechanisms at the end of the next chapter. Separation of minerals by fractional crystallization.

Illustration of how the earliest formed minerals can be separated from a magma by settling. 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.

Faure discusses fractional crystallization relating to U and Th in his book p. These values may be taken as an indication of the very dating abundance of these elements in the radiometric and crust of the Earth. In the course of skinhead dating website melting and fractional crystallization of magma, U failures 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 Failures has resulted in the concentration of U and Th into the rocks of radiometric continental crust compared to those of the upper mantle. The concentration of Pb is usually so much higher than U, radiometric a 2- radiometric 3-fold increase of U doesn't change the percent composition much e.

Finally, we have a third quotation from Elaine G. Kennedy in Geoscience Radiometric, SpringNo. Contamination and fractionation issues are frankly acknowledged by the geologic community. 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 key to successful dating 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. 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 failures 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 radiometric 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 dating 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 failures 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 failures 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 -- radiometric 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 radiometric one has repeated melting and solidification, introducing more complications. There is also a fourth mechanism -- differences in solubilities. Dating sites gothic 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 dating 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: The magnesium and iron rich minerals come from the mantle subducted oceanic plateswhile granite comes from continental sediments crustal rock.

The mantle part solidifies first, and is rich in magnesium, iron, and calcium. 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.


Thank you for signing up to receive email newsletters from Answers in Genesis. Tarbuck and Lutgens carefully explain the process of fractional crystallization in The Earth: I believe that all parent substances are water soluble, and many of the daughter products as well.

Coments: 2
  1. doctorfake

    This also justifies Slusher's statements about argon moving in and out of rocks with ease. Alvarez W, Asaro, F.

  2. tomase

    However, the U-Th-Pb method uses a different procedure that I have not examined and for which I have no data.

Add comment