K-ar age dating. How do we assess the published K

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K/Ar age dating of the ophiolitic Nicoya Complex of the Osa Peninsula, southern Costa Rica

k-ar age dating

I showed that the fact that the great majority of dates come from one method K-Ar and the fact that many igneous bodies have very wide biostratigraphic limits, where many dates are acceptable, makes the percentage of anomalies irrelevant to the question I am asking. To be exact, Bowen's Reaction Series was the one diagram that I was required to memorize when I took my first geology course in college. When volcanic material flows over the land, the naturally occurring Argon gas is driven off by the excess heat. So one obtains a series of minerals crystallizing out of the lava. I realize that geologists say the polystrate fossils trees extending through many layers fell into place later on, but these fossils are very common, and a logical corollary of catastrophic deposition. Bishop James Ussher, a 17th-century Irish cleric, for example, calculated that creation occurred in 4004 B. Samples with flat plateaus which should mean no added argon can give wrong dates.


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Potassium

k-ar age dating

It's also possible for other matter to be incorporated into lava as it rises, without being thoroughly melted, and this matter may inherit all of its old correlated radiometric dates. Mixing in such systems has been found , , but the Rb-Sr method is rarely used on these systems. And even for this one, the results were not very good. The moon is slowly sapping the earth's rotational energy. This simplified conceptual treatment does not give a fair picture of the detailed design and execution of age determinations for a wide variety of types of geological samples.

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K/Ar age dating of the ophiolitic Nicoya Complex of the Osa Peninsula, southern Costa Rica

k-ar age dating

Uranium decays to lead by a complex series of steps. Argon is released from lava as it cools, and probably filters up into the crust from the magma below, along with helium and other radioactive decay products. All its argon will either remain inside and give an old age to the flow, or will travel through surrounding rock, where it can be absorbed by other rocks. Still another evidence for problems with radiometric dating was given in a recent talk I attended by a man who had been an evolutionist and taken a course in radiometric dating. This would also make deeper rocks tend to have older radiometric ages. Some samples will not be fully reset, initially.

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(K/Ar) Potassium Argon Dating Techniques I

k-ar age dating

Geologists explain the Kaupelehu date by the lava being cooled rapidly in deep ocean water and not being able to get rid of its enclosed argon. The rates of exchange that would mess up the dates are very tiny. Note that if there are small pockets in crystals where both parent and daughter product can accumulate from the lava, then one can inherit correlated ages from the lava into minerals. During most of our interchange, I was not aware that it would be published on talk. This is probably the assumption that scientists make when they choose to present filtered data in a scientific paper. Behind the arc, openings are detected in Colombia. First, there must be no argon other than that of atmospheric composition trapped in the rock or mineral when it forms.

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Potassium

k-ar age dating

He does this as well for the forests of Joggins Petrified Trees of Nova Scotia. The 87Rb and 87Sr contents are normalized to the amount of 86Sr, which is not a radiogenic daughter product. They noted, 'The solubility of Ar in the minerals is surprisingly high'. I believe that bentonite occurs in a number of formations of different geologic periods, so this could be checked. If in fact such an answer were found, it would be quickly dismissed.

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How Old is the Earth: Radiometric Dating

k-ar age dating

There is no way to correct for this natural isotopic variation since there is no way to determine it. It is made of a very thick sequence of massive and pillowed tholeiitic flows with scarce sedimentary intercalations, where microfauna are Campanian- Maastrichtian, Upper Paleocene-Lower Eocene, Middle-Upper Eocene Di Marco, 1994. Is this a warranted assumption? Earth Planet Sci Lett 1969;6:47-55 has dated several lava flows which are known to have erupted in modern times. Unbeknownst to the scientists engaged in this controversy, however, geology was about to be profoundly affected by the same discoveries that revolutionized physics at the turn of the 20th century. Here is some relevant information that was e-mailed to me. Heating causes the crystal structure of the mineral or minerals to degrade, and, as the sample melts, trapped gases are released.

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Ar

k-ar age dating

It seems most likely that the uranium entered at the same time as the polonium. Instead, data from this Mount St. The oldest event dates back to the Santonian 78±2Ma ; a second well-defined event took place during the Paleocene, peaking at around 60. If you were to measure Ar40 concentration as function of depth, you would no doubt find more of it near the surface than at deeper points because it migrates more easily from deep in the earth than it does from the earth into the atmosphere. We also need to know that no parent or daughter has entered or left the system in the meantime. But, in practice, how do we assess the reliability and uncertainty of the published K-Ar age data? The problem with this approach is that it leaves ample room for the exercise of subjective judgment and evolutionary assumptions.

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Potassium

k-ar age dating

Helens dacite, many scientists have been able to isolate specific minerals from older volcanics and successfully date them. If this is so, then why do they say the method is accurate to 50,000 years? About 10 million years ago, the Panama-Costa Rica arc began to collide with northwestern South America, cutting off the deep-water circulation between the Pacific and the Caribbean. Geological Society of America Abstracts with Programs, 25:A-462. There must have been no incorporation of Ar40 into the mineral at the time of crystallization or a leak of Ar40 from the mineral following crystallization. It's also not uncommon for two methods to agree and for the date to be discarded anyway. Second, there may have been a lot more more argon in the magma in the past, and with each eruption, the amount decreased. The older method required splitting samples into two for separate potassium and argon measurements, while the newer method requires only one rock fragment or mineral grain and uses a single measurement of isotopes.

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K/Ar age dating of the ophiolitic Nicoya Complex of the Osa Peninsula, southern Costa Rica

k-ar age dating

These anomalies are reported in the scientific literature. Recent studies of convergent plate margins and the structural development of forearc terranes are summarized in a critical review of U. Thus one could pick the dates that fit one's expectations and create a very impressive list of dates with close agreement without there being more than a general correlation of most dates with one's expectations. It is easy to see how the huge ages are being obtained by the K40-Ar40 radiometric clock, since surface and near-surface samples will contain argon due to this diffusion effect. So, many people try to say something like: the weight of evidence proves evolution; or, all the data supports evolution. However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over 500 million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old. The last four mineral concentrates were prepared from the whole rock by heavy liquid and magnetic separation.


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