The reason scientists normalize with another stable isotope of the same element as the daughter is because most chemical or physical processes that occurs normally in nature does not differentiate between different isotopes of the same element when the difference in mass is as small as it is between isotopes of the same element that is used in radiometric dating.
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 the earth and life.
Contrast with these inaccurate dating methods,Scientific facts, such as the almost total lack of moon dust, lunar.
The heat of the impact melted some of the feldspar crystals in the granitic rocks of the impact zone, thereby resetting their internal radiometric clocks.
, using rigorous methods have established a process to eliminate this problem by calibrating radiocarbon dating results to items of a known age.
You know something use kevins words as a sort of journal review to explain why you can be sure that the radiometric dating assumptions applied to measure parent isotope a and compare to daughter isotope b to get the age of a rock can be trusted.
Only substances with much longer half-lives are used for dating the age of the earth, such as radioactive forms of rb (rb-87), which has a half-life of 48 billion years.
These claims generally land in three different categories: (1) radiometric dating assumes that initialClocks in the rocksthe following radioactive decay processes have proven particularly useful in radioactive dating for geologic processes: lead isochrons are also an important radioactive dating process.
Some of the decays which are useful for dating, with their half-lives and decay constants are: parent isotope(radioactive)daughter isotope(stable)half-life(gy)decay constant(10-11yr-1)40k40ar*1.
Not only that, they have to show the flaws in those dating studies that provide independent corroborative evidence that radiometric methods work.
Problems with radiometric dating of rocks
Creationist approach of focusing on examples where radiometric dating yields incorrect results is a curious one for two reasons.
In order to accomplish their goal of discrediting radiometric dating, however, creationists are faced with the daunting task of showing that apreponderanceof radiometric ages are wrong that the methods are untrustworthymostof the time.
Clocks in the rocksindexbeta decay concepts hyperphysics***** nuclear r navego backpotassium-argon method potassium-argon dating has the advantage that the argon is an inert gas that does not react chemically and would not be expected to be included in the solidification of a rock, so any found inside a rock is very likely the result of radioactive decay of potassium.
Furthermore, the dating was done in 6 different laboratories and the materials were collected from 5 different locations in the western hemisphere.
These claims generally land in three different categories: (1) radiometric dating assumes that initial conditions (concentrations of mother and daughter nuclei) are known, (2) radiometric dating assumes that rocks are closed systems and (3) radiometric dating assumes that decay rates are constant.
In the rocksindex hyperphysics***** nuclear r navego backmoon rock dating the ages of rocks returned to earth from the apollo missions range from 3.
The fact of the matter is youre claiming radio-dating methods are useful for dating, were both proving here that they arent.
Are many different kinds of radiometric dating and not all conclusions we will reach can be extrapolated to all methods used.
How could all of this be so if the40ar/39ar dating technique did not work?
Second, the radiometric age measurements, 187 of them, were made on 3 different minerals and on glass by 3 distinctly different dating methods (k-ar and40ar/39ar are technical variations that use the same parent-daughter decay scheme), each involving different elements with different half-lives.
Problems with radioactive dating methods
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.
All the dating methods are provably inaccurate, unless you just take one reading and assume that its right because it fits your expectation.
You are attempting carbon dating on dino bones or natural diamonds, the you have no idea what is going on.
Why is there significant amounts of c14 in dino bones that we can measure within dating error bounds?
Also, different radiometric dating techniques independently converges with each other and with other dating techniques such as dendrochronology, layers in sediment, growth rings on corals, rhythmic layering of ice in glaciers, magnetostratigraphy, fission tracks and many other methods.
Hyperphysics***** nuclear r navego backmeteorite dating "meteorites, which many consider to be remnants of a disrupted planet that oriaginally formed at about the same time as the earth, have provided uranium-lead and rubidium-strontium ages of about 4.
(and unlike what is claimed by the creationists), scientists have known about a variety of methods that create carbon-14 and how those methods have varied over time.
Just looking at this list, i can see that none of these are actually assumptions used by radioactive dating methods and/or they are known issues and compensated for.
Usually determinations of age are repeated to avoid laboratory errors, are obtained on more than one rock unit or more than one mineral from a rock unit in order to provide a cross-check, or are evaluated using other geologic information that can be used to test and corroborate the radiometric ages.
While this is technically true, there are several mini-industries dedicated developing methods and techniques to make sure that there is no contamination and check to see if the rocks where disturbed between forming and being tested by scientists.
Problems with radiometric dating methods
Two extensive studies done more than 25 years ago involved analyzing the isotopic composition of argon in such flows to determine if the source of the argon was atmospheric, as must be assumed in k-ar dating (dalrymple 1969, 26 flows; krummenacher 1970, 19 flows).
Not only that, different radioactive isotopes decay differently and it is enormously improbable that a postulated difference in decay rates would affect all of them in the same way, yet as we have seen, different radiometric dating methods converge on the same date (within margins of error).
Lets see what the missing universe museum thinks are the assumptions of radioactive dating methods.
Scientists have concluded that it is not; it is instead a consequence of the fact that radiometric dating actually works and works quite well.
Dating of meteoritesmoon rocksmodeling the age of the earthradionuclides sorted by half-livesindexreferencesdalrymple hyperphysics***** nuclear r navego backuranium-lead datingages determined by radioactive decay are always subject to assumptions about original concentrations of the isotopes.
Few verified examples of incorrect radiometric ages are simply insufficient to prove that radiometric dating is invalid.
You had 100% pure parent element when you began a dating process, then radioactive dating would be extremely reliable since the radioactive half-life of a given isotope is quite independent of any natural forces save direct collision-type interactions with the nucleus.
, you see, there are 3 known methods for diamonds to have c14 and thats why certain samples are inappropriate for use as dating samples.
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.
In fact, just considering that model, we can ice layers, coral growth, tree rings, stratigraphy, and several other methods all of which show earth must be older than the 10,000 years of the yec model.
Problems with radiometric dating techniques
Youre going to argue that contamination somehow caused a replenishment of diamond c14, then you cant possibly believe that any radiometric dating method is reliable if something as robust as c14 decay in something as impermeable as diamond cant ever be trusted to date something, how can you honestly assert that rocks have not been subject to isotope contamination in the same manner?
So where are the experiments that show that u-pb, k-ar, rb-sr, u-th, ar-ar, i-xe, la-ba, pb-pb, lu-hf, re-os, u-pb-he, u-u arent subject to the assumptions of initial conditions (or mixing conditions for isochron dating), no contamination and an unchanging decay rate?
Tomorrow where we explore the concept of isochron dating and how it neatly destroys most of the rest of these issues.
Other creationists have focused on instances in which radiometric dating seems to yield incorrect results.
Method and problems with uranium and thorium dating,We will frequently refer to both under the category of uranium dating.
Scientists who use radiometric dating typically use every means at their disposal to check, recheck, and verify their results, and the more important the results the more they are apt to be checked and rechecked by others.
Other dating techniques, like k-ar (potassium-argon and its more recent variant40ar/39ar), rb-sr (rubidium-strontium), sm-nd (samarium-neodynium), lu-hf (lutetium-hafnium), and u-pb (uranium-lead and its variant pb-pb), have all stood the test of time.
The above principle, we could arrive with weird and illogical conclusion below that would place the reliability of radiometric dating method into question:If anyone of atoms, lets say, atom a, has been selected from a parent isotope, lets say, lutetium, to test the radioactive decay, this atom would surely have 50% of its atomic nucleus to be activated in radioactive decay in accordance to the 50% remaining rule as mentioned above.
Results of the manson impact/pierre shale dating study (izett and others 1998) are shown in figure 1.
Some so-called creation scientists have attempted to show that radiometric dating does not work on theoretical grounds (for example, arndts and overn 1981; gill 1996) but such attempts invariably have fatal flaws (see dalrymple 1984; york and dalrymple 2000).
Billion years old, by far the oldest ever found on the earth" this dating was done on grains of zircon, a mineral so stable that it can retain its identity through volcanic activity, weathering, and sedimentation.
According to your belief in dating methods that should mean you accept that the dated acrocanthosaurus is 24,750 (+/- 280) years old and the allosaurus is 31,360 (+/- 160) years old.
The 40ar/39ar technique, which is now used instead of k-ar methods for most studies, has the capability of automatically detecting, and in many instances correcting for, the presence of excess40ar, should it be present.
The ease to locate carbon-14 that would respond to decay currently has put the reliability of radiometric dating method into question.
For example, for carbon-14, it would take 5730 years for the 50% of the initial remaining to turn up to lose its capability in radioactive decay in order to have 50% of what has remained after the initial remaining to activate radioactive dating.
As a result, it is nearly impossible to be completely fooled by a good set of radiometric age data collected as part of a well-designed experiment.
Reliability of percentage remaining (50% of the remaining rule) that has been used by scientists for the relative half-lives elapsed in responding to radiometric dating method is in question.
Again, thats not a wild guess but a convergent figure based on several different radiometric dating methods, study of meteorites and samples from the moon.
Didnt mention how c14 can still be present in diamond, and if it somehow magically can through contamination somehow, how you can trust any dating at all due to contamination?
And the fact that even isochron dating gives consistently unexpected results even for samples taken from the same rock, and especially for lava flows of known age.
?With respect to isochron dating, samples from the western canyon basalt lava flows (some of the youngest) were analyzed.
In the rocksage of the moonindexreferencedalrymplech 5 hyperphysics***** nuclear r navego backage of the moon our best clues to the age of the moon are the radiometric dates of the oldest moon rocks, those from the lunar highlands.
A very important tool in radiometric dating is the so called isochron diagram and it holds the key to refuting the central creationist claims about radiometric dating.
A critical examination of stefan molyneuxs claims aboutantidepressantshow to critically read and evaluate a scientificpaper categories: debunking creationism, science explained, skepticismtags: assumptions, closed system, creationism, dating methods, decay rates, initial conditions, isochron.
It is these studies, and the many more like them documented in the scientific literature, that the creationists need to address before they can discredit radiometric dating.
, i notice that the papers conclusion, that older rocks have larger error ranges, is not at all surprising, nor is it a problem for science, radiometric dating, or evolution.
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.
Young earth creationists often claim that the speed of light, radiometric decay rates and the motions of the planets could have been different, but the magnitude of the difference would cause the earth to be vaporized, and no yec, not a single one, has provided an estimate of what those speeds and rates should have been, how they changed and why they are stable today.
Of the great things about many forms of radiometric dating is that they are self-checking.
Those of us who have developed and used dating techniques to solve scientific problems are well aware that the systems are not perfect; we ourselves have provided numerous examples of instances in which the techniques fail.