Radiometric dating

Bring fact-checked results to the top of your browser search. Importance of zircon in uranium-lead dating The mineral zircon adds three more fundamental advantages to uranium—lead dating. First, its crystal structure allows a small amount of tetravalent uranium to substitute for zirconium but excludes with great efficiency the incorporation of lead. It might be said that one begins with an empty box. Second, zircon, once formed, is highly resistant to change and has the highest blocking temperature ever observed. Finally, with few predictable exceptions, zircon grows or regrows only in liquid rock or in solid rock reheated to approach its melting point.

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Historical connections[ edit ] Technologies, including communications technologies, have a long history of shaping and being shaped by the gender of their users. Although technologies used to perform housework have an apparent historical connection to gender in many cultures, [1] a more ready connection to SNSs may be drawn with telephones as a communications technology readily and widely available in the home.

Telephone use has long had gendered connections ranging from the widespread assumption that women simply talk more than men, and the employment of women as telephone operators. In particular, young women have been closely associated with extensive and trivial use of the telephone for purely social purposes. There is historical and contemporary evidence that current fears about young girls’ online safety have historical antecedents such as telegraphs and telephones.

Further, in many cases those historical reactions resulted in restrictions of girls’ use of technology to protect them from predators, molesters, and other criminals threatening their innocence.

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More educated online daters are more likely to positively assort. Abstract To identify the factors that influence educational assortment in an online dating setting, we analyse , participant contacts by 41, members of the Australian online dating web site RSVP over a four-month period. Consistent with prior research, we find that more educated online daters are consistently likely to assort positively homogamy meaning that they are more likely to contact potential mates with the same level of education.

However, as the more educated cohort gets older they care less about homogamy while less educated daters become more interested in homogamy which leads to an increase in similarity towards caring for the same educational level. On the other hand, older and more educated online daters are less likely to contact those with lower educational levels compared to their own while women are more likely to contact a potential mate with higher educational levels relative to their own hypergamy.

Our interaction analysis also reveals fewer differences in educational hypergamy among older online participants but a greater likelihood of online daters contacting mates with lower levels of education among younger males and older females. Further research is therefore warranted on technology’s impact on human mating behaviour; in particular, the psychology employed by humans using the Internet to maximize their chances of matching their educational preferences in a mate.

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How radiometric dating works in general: Radioactive elements decay gradually into other elements. The original element is called the parent, and the result of the decay process is .

Radioactive decay[ edit ] Example of a radioactive decay chain from lead Pb to lead Pb. The final decay product, lead Pb , is stable and can no longer undergo spontaneous radioactive decay. All ordinary matter is made up of combinations of chemical elements , each with its own atomic number , indicating the number of protons in the atomic nucleus. Additionally, elements may exist in different isotopes , with each isotope of an element differing in the number of neutrons in the nucleus.

A particular isotope of a particular element is called a nuclide. Some nuclides are inherently unstable. That is, at some point in time, an atom of such a nuclide will undergo radioactive decay and spontaneously transform into a different nuclide. This transformation may be accomplished in a number of different ways, including alpha decay emission of alpha particles and beta decay electron emission, positron emission, or electron capture.

Another possibility is spontaneous fission into two or more nuclides. While the moment in time at which a particular nucleus decays is unpredictable, a collection of atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life , usually given in units of years when discussing dating techniques.

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Primary source references As a preface to this document, I want to point out that it is a shame that we have to continue to refute the same arguments that evolutionists keep bringing up over and over again in their attempts to argue against the fact of creation, which fact has been well established since the day the earth was created ex nihilo several thousand years ago.

It is also a shame that the masses have bought all this based on some circular reasoning about fossils, where fossils tend to be found buried, similarities between various life forms, the presence of certain decay products in rocks, and other inherently speculative arguments about the past, based on phenomena that exist in the present. If I hope to accomplish anything, it will be to simply encourage critical thinking.

One must get past the arguments ad populum that its popularity counts for something , ad hominem that if you attack the person making the argument, this counts for something , and especially ad baculum that there are people who have the clout to decree it as true , to ask the key questions and challenge the unsubstantiated assumptions and thinking of those who would hold to the evolution position.

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Lunar breccias, formed largely by the immense basin-forming impacts, are dominantly composed of highland lithologies because most mare basalts post-date basin formation and largely fill these impact basins. The ferroan anorthosite suite is the most common group in the highlands, and is inferred to represent plagioclase flotation cumulates of the lunar magma ocean, with interstitial mafic phases formed from trapped interstitial melt or rafted upwards with the more abundant plagioclase framework.

This reflects the extreme depletion of the bulk moon in alkalis Na, K as well as water and other volatile elements. Ferroan anorthosites have been dated using the internal isochron method at “circa” 4. These rocks represent later intrusions into the highlands crust ferroan anorthosite at round 4. An interesting aspect of this suite is that analysis of the trace element content of plagioclase and pyroxene require equilibrium with a KREEP -rich magma, despite the refractory major element contents.

The alkali suite is so-called because of its high alkali content—for moon rocks. The alkali suite consists of alkali anorthosites with relatively sodic plagioclase An , norites plagioclase-orthopyroxene , and gabbronorites plagioclase-clinopyroxene-orthopyroxene with similar plagioclase compositions and mafic minerals more iron-rich than the magnesian suite. The alkali suite spans an age range similar to the magnesian suite. Lunar granites are relatively rare rocks that include diorites , monzodiorites, and granophyres.

They consist of quartz, plagioclase, orthoclase or alkali feldspar, rare mafics pyroxene , and rare zircon. The alkali feldspar may have unusual compositions unlike any terrestrial feldspar, and they are often Ba-rich. These rocks apparently form by the extreme fractional crystallization of magnesian suite or alkali suite magmas, although liquid immiscibility may also play a role.

U-Pb date of zircons from these rocks and from lunar soils have ages of 4.

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View images by clicking on link or reduced image: Each image opens into a new window. These primitive, medium sized apes lived in rain forests between 18 and 22 million years ago. This species and others such as Dryopithecus existed before the hominid line diverged on the path to humans. This lineage ancestral gibbons is believed to have diverged from the great ape and human lineages between 17 and 25 Mya Avers,

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After a first selection to eliminate polluted samples, based on visual inspection, on proper mechanical tests and on a first glance at the resulting spectra, eleven samples of the original 14 have been used for Raman analysis and eight for FT-IR analysis. For the first time, the possibility to define a correlation among spectral properties and age of flax samples, by using calibration curves, has been proved.

In agreement with the kinetics theoretical model, the experimental relationships are of an exponential type, giving correlation coefficients higher than 0. The better results were obtained using FT-IR because Raman analysis needs to consider an additional variable due to the non negligible influence of fluorescence. Presently, the method allows to assign an uncertainty of centuries to the measured data, but future calibrations based on a greater number of samples though it is not easy to find ancient samples adequate for the test and coupled with ad hoc cleaning procedures could significantly improve its accuracy.

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Primary igneous rocks in the lunar highlands compose three distinct groups: Lunar breccias, formed largely by the immense basin-forming impacts, are dominantly composed of highland lithologies because most mare basalts post-date basin formation and largely fill these impact basins. The ferroan anorthosite suite is the most common group in the highlands, and is inferred to represent plagioclase flotation cumulates of the lunar magma ocean, with interstitial mafic phases formed from trapped interstitial melt or rafted upwards with the more abundant plagioclase framework.

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The Radiometric Dating Game Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium. On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years. We are told that these methods are accurate to a few percent, and that there are many different methods.

We are told that of all the radiometric dates that are measured, only a few percent are anomalous. This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points. Since there doesn’t seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate.

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 million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old. If these dates are correct, this calls the Biblical account of a recent creation of life into question.

After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found. I believe that there is a great need for this information to be made known, so I am making this article available in the hopes that it will enlighten others who are considering these questions.

Even the creationist accounts that I have read do not adequately treat these issues. At the start, let me clarify that my main concern is not the age of the earth, the moon, or the solar system, but rather the age of life, that is, how long has life existed on earth.

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