A Response to Scientific Creationism
Since the decay rate is also unsettled, values of these constants are chosen which bring potassium dates into as close correlation with uranium dates as possible. Just how much lead and were present at the beginning, nobody knows. Neutrinos are particles that are emitted during beta decay. This correction can be made very accurately and has no appreciable effect on the calculated age unless the atmospheric argon is a very large proportion of the total argon in the analysis. Because this type of decay involves a particle outside the nucleus, the decay rate may be affected by variations in the electron density near the nucleus of the atom.
Age estimates which are obviously wrong or contradictory are sometimes produced. Most radioactive decay involves the ejection of one or more sub-atomic particles from the nucleus. Most commonly, the event causes partial or total loss of the radiogenic daughter isotope, resulting in a reduced age. Others, primarily the stone meteorites called chondrites, seem to represent rocks essentially unchanged since condensation from the solar nebula. The U-Pb concordia-discordia method is one of the most powerful and reliable dating methods available.
How Do We Know the Earth Is Billion Years Old
The lowest ratios are taken to be the most ancient ores, formed at the beginning, billions of years ago and separated from further radiogenic enrichment. Thus the assumption of immense ages has not been proven. One of the principal tasks of the geochronologist is to select the type of material used for a dating analysis. It is especially resistant to heating and metamorphic events and thus is extremely useful in rocks with complex histories. It is, therefore, more correct to talk about formational intervals rather than discrete ages for the Solar System and the Earth.
By the mid- to late s, geologists, physicists, and chemists were searching for ways to quantify the age of the Earth. Many of these samples have not had so intense nor so complex histories as the oldest Earth rocks, and they commonly record events nearer or equal to the time of formation of the planets. If the Earth, the Moon, and meteorites were not genetically related and of the same age, there would be no reason for their Pb-isotopic compositions to lie along the same isochron. Fourth, if isochrons were the result of mixing, internet dating alias approximately half of them should have negative slopes.
The results were similarly bad. Unlike argon, which escapes easily and entirely from most molten rocks, strontium is present as a trace element in most minerals when they form. If these three age calculations agree, then the age represents the true age of the rock. It commonly substitutes for calcium in calcium minerals, text dating service such as the plagioclase feldspars.
The Mythology of Modern Dating Methods. The changing ratio of C to C indicates the length of time since the tree stopped absorbing carbon, i. Also, I think it is worth mentioning that while Martin mocks the hour glass analogy, he completely fails are providing any type of refutation of it. It should be obvious that the further one projects present rates, the more likely one is to be quite wrong.
Two cases where it appears that the half life is increasing with time are as follows. Lead, however, is a volatile element, and so lead loss is commonly a problem. The validity of the calculated date can be no stronger than the weakest link weakest assumption used in the calculation. In theory, it might be useful to archaeology, but not to geology or paleontology.
Lead, a minor isotope of common lead, has no radioactive parent and is believed to be primordial lead. The points represent analyses on glass, tridymite and quartz, pyroxene, total rock, and plagioclase. It is only useful for once-living things which still contain carbon, like flesh or bone or wood. In reality, its measured disequilibrium points to just such a world-altering event, why is dating not many years ago.
For radiometric dating the system, usually a rock or some specific mineral grains, need only be closed to the parent and daughter isotopes. Don't attack individuals, denominations, or other organizations. This is in response to Martin H. The K-Ar clock works primarily on igneous rocks, i.
How Old is the Earth Radiometric Dating
The Carbon age estimating method is, at best, only useful for estimating the age of things that are thousands of years old, not millions or billions. Certainly this is not produced by an influx from outer space. Because these types of radioactive decay occur spontaneously in the nucleus of an atom, the decay rates are essentially unaffected by physical or chemical conditions.
It has often been wrongly assumed that no outside factors altered the normal ratios in the material, adding or subtracting any of the elements involved. Age estimates on a given geological stratum by different radiometric methods are often quite different sometimes by hundreds of millions of years. Cook notes the apparent absence of thorium and Pb, and the presence of Pb.
There are two things wrong with this argument. Stone meteorites commonly contain small amounts of nickel-iron, nadi astrology and many iron meteorites include small amounts of silicate minerals. Researchers have also pointed out various reasons why small changes in decay rates in modern laboratory work would tend to be overlooked. Mineral composition and the sequence of mineral formation are governed by chemical laws and do not involve mixing.
The U-Pb concordia-discordia method circumvents the problem of lead loss in discordant systems and provides an internal check on reliability. The chemical properties of rubidium and strontium are so dissimilar that minerals which readily accept rubidium into their crystal structure tend to exclude strontium and vice versa. Hi Martin, The uncertainty of less than one percent that you quote relates to the laboratory precision.
Sometimes these decay schemes are used individually to determine an age e. If the requirements of the method have been violated, the data clearly show it. It disintegrates at a measured rate into calcium and argon. Moreover, many of the oldest dated rocks intrude still older but undatable rocks. But he and other anti-creationists like to pretend otherwise, in order to deceive the naive.
We know the Earth is old. But how do we know its age
- This estimate was deduced from the ratios of different lead isotopes found in meteorites, Moon rocks, and Earth rocks.
- It is chemically similar to potassium and tends to substitute for that element in minerals in which potassium is a major constituent, such as potassium feldspar and the micas muscovite and biotite.
- Rb and Sr are quite different elements and are incorporated into the various minerals in varying proportions according to the composition and structure of the minerals.
- Stone meteorites are composed primarily of the silicate minerals olivine and pyroxene, whereas iron meteorites consist primarily of nickel-iron alloy.
The reader can easily satisfy himself on this point by reading the report by Steiger and Jaeger and the references cited therein. As the reader can easily see, the Rb-Sr isochron method is elegantly self-checking. There has been in recent years the horrible realization that radio-decay rates are not as constant as previously thought, nor are they immune to environmental influences. Once the tree dies, it ceases to take in new carbon, and any C present begins to decay. Any amounts chosen must be based on assumption.
- How dating methods work tract.
- Ah, the inspiring is the hourglass analogy.
- Scientific measurements of decay rates have only been conducted since the time of the Curies in the early s.
- He reasons that the Pb could not have come from the decay of Th because thorium is absent, and could not be common lead because Pb, which is present in all common lead, is absent.
- These authors studied dikes of basalt that intruded Precambrian crystalline basement rocks and Mesozoic sedimentary rocks in western Liberia.
All those scientists could very well be wrong simply because they started with an assumption that is faulty. This limit is shown in Fig. Therefore, if the extrapolation shown in Fig. What are some of the assumptions made by most Evolutionists in using these systems? It is so helpful to see the arguments pedalled as truth receive such accurate rebuttals.
Assumptions and More Assumptions
Theoretically, Creationism remains workable within a wide range of age estimates. Carbon normally occurs as Carbon, but radioactive Carbon may sometimes be formed in the outer atmosphere as Nitrogen undergoes cosmic ray bombardment. Radiometric dating is based on the decay of long-lived radioactive isotopes that occur naturally in rocks and minerals. They observed that every rock formation, no matter how ancient, appeared to be formed from still older rocks.
How Old is the Earth Scientific Age of the Earth
He claims that these examples cast serious doubt on the validity of radiometric dating. It might be argued that although radiometric dating has a few problems, the large body of concordant data using different isotopes shows that the dates are of the right order. These changes are irrelevant to radiometric dating methods.