The real heart of the age-of-the-earth debate (if "debate" is the right word)
is always radiometric dating. There are lots of ways to guesstimate ages, and
geologists knew the earth was old a long time ago (and I might add that
they were mostly Christian creationist geologists). But they didn't know how
old. Radiometric dating actually allows the measurement of absolute ages,
and so it is deadly to the argument that the earth cannot be more than 10,000
years old.
Radiometric methods measure the time elapsed since the particular radiometric
clock was reset. Radiocarbon dating, which is probably best known in the general
public, works only on things that were once alive and are now dead. It measures
the time elapsed since death, but is limited in scale to no more than about
50,000 years ago. Other methods, such as Uranium/Lead, Potassium/Argon,
Argon/Argon and others, are able to measure much longer time periods, and are
not restricted to things that were once alive. Generally applied to igneous
rocks (those of volcanic origin), they measure the time since the molten rock
solidified. If that happens to be longer than 10,000 years, then the idea of a
young-Earth is called into question. If that happens to be billions of years,
then the young-Earth is in big trouble.
As of January, 1999, The oldest rocks found on earth are 4.031 ± 0.003
billion years old (meaning it has been that long since the molten rocks
solidified and thus reset their internal clocks). This is reported in the paper
Priscoan (4.00-4.03 Ga) orthogneisses from northwestern Canada by Samuel A. Bowring &
Ian S. Williams; Contributions
to Mineralogy and Petrology 134(1): 3-16, January 1999. The previous record
was 3.96 billion years, set in 1989.
The putative age of the Earth, about 4,500,000,000 years is based on the
radiometrically measured age of meteorites, and is also about 500,000,000 years
older than the oldest rocks. But regardless of the accuracy of this age for the
earth, the existence of rocks circa 4,000,000,000 years old puts the squeeze on
a 10,000 year old Earth.
So the natural response from a young-Earth perspective is to claim that
radiometric dating is inaccurate or untrustworthy. Unfortunately, while the
young-Earthers are long on criticism, they are short on support. It's easy to
assert that radiometric methods don't work, but it's quite another thing
to prove it. This the young-Earth creationist regularly fails to do.
I am not going to try to write a web-treatise on radiometric dating myself,
simply because much better qualified writers have already done a much better job
than I could. This is a list of resources, some on the web, some not, which can
be consulted by anyone interested in learning more about how radiometric dating
is done, or in responding to arguments criticising radiometric dating. My
purpose is to show, through these resources that young-Earth creationist
criticisms of radiometric dating are inadequate at best. So long as radiometric
dating stands as scientifically valid, then the assertion of a young-Earth is
falsified by direct observation. The argument from radiometriic dating is the
strongest scientific argument that can be brought to bear on this issue, in my
opinion.
There may be some sense of repetition, as there are a number of one-page,
introductory type entries. But I put them all in anyway, figuring some readers
would understand one more easily than the other.
A Creation Perspective is
the title of Dr. Plaisted's creation page. It is an extensive collection of
pro-creationist material that extends well beyond radiometric dating. So far
as I know all of the material was written by Dr. Plaisted. One of those
articles, "The
Radiometric Dating Game", which also appears in the True Origins Archive,
was the focus of Dr. Henke's Criticism. Part
1 is a critique posted by Dr. Henke on the talk.origins newsgroup in early
December 1998. Part
2 and Part
3 constitute the text of a discussion between Henke & Plaisted, that
followed the posting of Henke's original critique; they date from late
December 1998. Part 2 was provided by Henke; it is Plaisted's response to the
critique with Henke's posted comments. Part 3 was provided by Plaisted, and
are his remarks in further response to Henke.
A Reply to Dr.
Henke and Others is a new page by David Plaisted, in direct response to
Henke's criticism's posted here, and in response to this Radiometric Dating
Resource List as well. Look for this page to change, or for new responses to
appear, as Dr. Plaisted continues his own research.
John
Woodmorappe is a pseudonymous pro young Earth creationist, and allegedly a
scientist. He is the author of several books and papers; one of those papers,
Radiometric Dating Reappraised is the target of Schimmrich's original
critique. Woodmorappe responded to that critique, hence Schimmrich's
additional response.
Since Woodmorappe is a popular source for pro young-Earth creationists,
this detailed discussion of his work by a qualified Christian geologist is a
good reference source. If the links above don't work, try Schimmrich's collection of
Christian Essays, where they can also be found.
Woodmorappe's
Collection of Bad Dates By David Matson Part of Dave
Matson's " How
Good Are Those Young Earth Arguments", an extensive collection of material
in response to young-Earth creationist Kent Hovind. "Carbon-14 and
Radiometric dating" is a collection of six articles in response to
Hovind's "Several Faulty Assumptions are used in Radiometric Dating".
"Woodmorappe's Collection of Bad Dates" is a critique of John
Woodmorappe's collection of about 350 allegedly "anomalous" bad radiometric
dates, which Woodmorappe intends as evidence that radiometric dating does not
work.
Dave Matson is a mathematician and editor of his own Oak Hill Free Press.
Responding to Creationists - Part
2 Responses to general creationst arguments
Radiometric Dating
and the Geological Time Scale - Circular Reasoning or Reliable Tools By
Andrew
MacRae MacRae received his PhD in Geology from the University of Calgary in 1996. This is a
well illustrated article that brings together stratigraphy, relative time
scales, and the absolute chronometry provided by radiometric dating. It is a
common assertion from young-Earthers that dating techniques are circular; that
fossils are dated according to their strata and that the strata are dated
according to their fossils. The assertion is flatly false.
Age of the
Earth by Robert Williams This is a general response to several
young-Earth arguments. The majority of material is on radiometric dating,
although some other faulty young-Earth age arguments are addressed as well.
Data, results, and faulty methodologies are all addressed. Of particular
interest is some tabulated data from Dalrymple's Age of the Earth (see
below). These data well illustrate the internal consistencies of radiometric
dating methods. A well written article worth reading.
Fresh Lava
Dated As 22 Million Years Old By Computer Scientist Don Lindsay A common
creationist argument is that radiometric dating must be unreliable, because
fresh Hawaiian lava was dated to be millions of years old. But this is an
urban legend, as Lindsay points out.
Were Adam & Eve
Toast? By Geophysicist Joe
Meert A common creationist argument is that radiometric dating must be
unreliable, because decay rates are variable, and were higher in the past. In
the reliability section below, there is a discussion of how rates might be
made to vary. But here Joe Meert explains the consequences we would expect
today, if in fact decay rates were variable in the past. The consequent very
high rate of energy release brings to mind the title question, Were Adam
& Eve Toast?
Consistent
Radiometric Dates By Joe
Meert, Associate Professor, Department of Geography, Geology and
Anthropology, at Indiana State
University. Meert shows where different radiometric methods return
concordant dates for a given sample or region. If radiometric dating really
does not work, one would not expect different methods to return concordant
ages. One more example of consistency, that leads to confidence that
radiometric dating is valid both in principle & in practice.
The
Formation of the Hawaiian Islands Hosted by The Hawaii Center for
Volcanology. The page inculdes a chart of radiometric ages of the
volcanoes in the Hawaiian chain. But the plot of age versus distance from Kilauea is
significant. It shows a clear linear slope, a strong, direct correlation
between the tectonic motion of the Pacific Plate over the Hawaiian
hotspot, and the age of the Hawaiian Island chain. Once more, a clear
correlation between radiometric dates, and independent date indicators.
Are
Radioactive Dating Methods Consistent with Each Other? By Computer
Scientist Don
Lindsay Two more items that address the question of reliability. In
these two short items, Lindsay shows that absolute radiometric dates are
consistent with relative geological dates, and that the various radiometric
methods are consistent with each other.
Breakthrough Made in
Dating of the Geological Record By F.J. Hilgen et al. From EOS 78(28): 285,288-289 (July 15,
1997), a weekly newspaper of geophysics from the American Geophysical Union. The
"breakthrough" documented in this report is an intercomparison between
sedimentary, radiometric and astrochronological
dates. This evidence of strong agreement between disparate dating methods is
another example of the consistency between radiometric dating and nature, and
another demonstration of reliability.
Comparing
Luminescence Dating and Radiometric Dating By Tim Thompson I wrote
this originally as a discussion board post, and decided to add it to this
collection. The Hilgen et al. paper above shows a convincing comparison
between radiometric dating and astronomical dating. Here, I reference a paper
that is a good example of concordance between radiometric dating and
luminescence dating, a technique that takes advantage of electrons
trapped in crystal lattice defects. The continued concordance between
radiometric and other dating schemes just makes things bleaker and bleaker for
the concept of a "young" Earth.
How to
Change Nuclear Decay Rates By Bill Johnson, updated by Scott
Chase. It is a common creationist ploy to argue that radioactive decay
rates either are, or can be, variable; since radiometric dating always assumes
a constant decay rate, it is therefore unreliable. But in this item from the
usenet physics
FAQ, we see how and why decay rates can and do vary. We also see that the
variable decay rate argument is a dead argument. Not only does the variability
not apply at all to most radiometric isotopes, but even in those cases where
it does apply, the affect is at the less than one percent level, under
conditions that are unrealistically extreme for any practical application to
radiometric dating.
Introductory General Articles on Radiometric
Dating
An Essay on
radiometric Dating By Jonathan Woolf An essay
on the basic principles. Woolf describes himself as an enthusiastic
amateur. But if you are looking for radiometric dating for dummies,
or some such explanation, aimed at the general reader, this may be the one
that does it for you.
Radiometric
Dating By Dr. Pamela J.W. Gore Hosted by Georgia Geoscience
Online and Georgia Perimeter
College; Dr. Gore is on the faculty of Georgia Perimeter College. This is
a brief tutorial introduction to the basic principles of radiometric dating,
designed for community college students of geology.
Geologic
Time By Dr.
Ethan L. Grossman A brief outline of the fundamental principles,
including radiometric dating. These are course notes for Dr. Grossman's
Geology 101 course, Department of Geology & Geophysics, Texas A&M
University.
Advanced General Articles on Radiometric
Dating These items presume some advanced understanding of physics
& mathematics
Isochron
Dating By Chris
Stassen The article is well illustrated and well written. There is an
introduction to the generic problem of radiometric dating, but this article
concentrates on one well established method called the "isochron method".
Isochron dating is a robust application of the radiometric principles which
has the advantage of being insensitive to the initial concentration of
daughter product. This is really an intermediate level article, designed for
general readers, but it is not something to read lightly.
Chris Stassen describes himself as a "computer hack with the bizarre hobby
of studying isotope geology". He is the owner of Stassen.Com.
Isotope
Geochemistry Lecture Notes Extensive graduate course lecture notes
downloadable in PDF format. Introduction to radioactive decay and
nucleosynthesis. Extensive notes on dating systems, radiogenic & stable
isotope geochemistry. Includes applications to palaeoclimatology. The entire
set of notes for 37 lectures will give you a 273 page book on isotope
geochemistry, free.
Radiocarbon Web Established
jointly by the radiocarbon laboratories at the University of Waikato in New Zealand, and
Oxford University in England, the
Radiocarbon Web is a storehouse of information on radiocarbon dating. Here you
will find a complete description of the basic principles, the applied
techniques, and how dates are corrected for the known variations in
atmospheric carbon abundances (the use of tree ring calibration is important).
Radiocarbon The homepage for
the technical journal Radiocarbon. Includes 14C Information
and Links to various radiocarbon laboratories, and downloadable software.
The project description is in English and in considerable detail. This is a
good example for those who want to see a detailed account of how it is all
really done. Includes 14C dating general principles &
methodology, absolute calibration, mass spectrometry, and archaeological
methods such as sample selection and preperation.
Carbon
Dating By Computer Scientist Don Lindsay A brief
introduction to carbon dating for general readers.
Other Resources Indirectly related to
radiometric dating
Webelements -
periodic table of the elements Webelements, hosted by the University
of Sheffield, England, is the most complete online periodic table I know of.
Complete physical, chemical, thermodynamic, and even historic information on
elements and isotopes. Not as much nuclear specific information as the table
of nuclides listed below, but lots of additional stuff.
These all mirror the same functionality, but the Korean interface is
actually a tad easier to use. This is where you look up things like decay
modes, half life, decay energy, and so forth. It's easier to work your way
through an entire decay chain using these tables, but if you want lots of info
on one element, the Webelements page is
better.
Books You remember - what we used to read
before computers
I have included here only such books as I know of, or are recommended. Some I
am aware of I have left off because they are out of print and I don't know much
about them. There are no "young-Earth" books here, because of course there are
no young-Earth radiometric dating methods established (no big surprise there).
Books included are both advanced and general, but all bear either directly or
indirectly on the radiometric dating problem. For each book, the title is linked
to an Amazon.Com entry if there is one (so
far we are batting 100%). Authors are linked to their own homepages, or the
functional equivalent, wherever I could find one.
The
Age of the Earth By G. Brent
Dalrymple Dalrymple earned his PhD in Geology from the University of California, Berkeley in
1963. A long time veteran of the U.S.
Geological Survey, he is now Dean of the College of Oceanic and Atmospheric
Sciences at Oregan State University. He
is a well recognized authority in the field of radiometric dating. His book,
published by the Stanford University Press
in 1991, is the only book I know of which deals directly and in detail with
the age of the Earth. It is written for non-technical readers, but it is not
lacking in content. 474 Pages long, the book covers all aspects of dating the
Earth, talks about the radiometric methods, and talks about the history of
attempts to determine the age of the Earth, including Biblical chronologies.
This book is a must-read for anyone interested in knowing how we know the age
of the Earth. It presents perhaps the strongest case against the idea of a
10,000 year old Earth.
Principles
of Isotope Geology By Gunter Faure Faure was
and still is a Professor in the Department of Geological
Sciences at Ohio State University; he
earned his PhD at M.I.T. in 1961. This book
is not for general audiences, it is a technical book aimed at students of
physics and geophysics. The book goes beyond an explication of the basic
principles, and delves into the applications of radiometric dating. An
excellent & detailed reference on the geology & physics of radiometric
dating, but Dickin's book (see below) is now in fair competition for the top
spot.
Radiogenic
Isotope Geology By Alan P.
Dickin Dickin is a professor in the School of Geography and
Geology at Mc Master University in
Hamilton, Ontario, Canada. The link goes to the 1997 reprint; the original
appeared in 1995. Dickin's home page includes a listing of the
appendix to the 1997 reprint which includes corrections and updates
applied from the 1995 edition (this is worth reading even if you don't buy the
book). Like Faure's book, this is a physicists text, not intended for general
audiences. Detailed explications of dating methods, as well as isotope
geochemistry. Includes fission track dating, which was not covered in my 1977
edition of Faure.
Radioactive
and Stable Isotope Geology By Hans-Gunter Attendorn & R.N.C
Bowen Amazon.com says it was published by Chapman & Hall, but they were
bought out by Kluwer. This is the 1997 second edition of
the 1988 "Isotopes in the Earth Sciences". Besides radiometric dating
methods and isotope geochemistry, this book also deals with isotopic analysis
and climate.
Nuclear
Methods of Dating By Etienne Roth et al., editors Graham
& Trotman, July 1990 Review - Booknews, Inc., May 1, 1990 Describes
all the methods of dating terrestrial events using direct or indirect
measurements of natural nuclear disintegrations. The work doesn't treat the
matter of isotopic geochemistry in general, but rather concentrates on a more
complete and practical guide to dating methods. The first chapter collates
general data and principles common to all methods. The following chapters
present the possibilities and limitations of the different dating methods,
along with the relevant analytical techniques and the preferred range of
application. Includes two glossaries, isotope tables, a scale of geological
times, and a chapter on radioactivity. Annotation copyright Book News, Inc.
Portland, Or.
