From: allenroy (allenroy@peoplepc.com)
Date: Wed Jan 08 2003 - 12:47:01 EST
Its been a little slow on the ASAnet so I thought I'd throw this out. :)
I have 3 points to make.
1: There is a distinction to be understood between computing apparent
ages according to certain assumptions from scientific quantification of
an assortment of isotopes in rock, and the acceptance of those dates as
valid for the rock involved. (Actually, the process of measuring
isotopes has evolved to the level of technology rather than scientific
experiment. Very few today conduct scientific experiments to measure
isotopes, rather, rock samples are submitted to labs who have the
technology to process the rock to measure contained isotopes.) I don't
know of any Creationary scientist who quarrels over the methodology,
accuracy and precision with which isotopes are measured and ages
computed. Most have, however, focused on the validity of assumptions of
radiometric dating. I would like to make another point.
I live not far from Grand Canyon, and in fact, I conduct Creationary
Cataclysmic tours there for those interested in hearing the latest
models concerning Noah's Flood. (see
http://www.tagnet.org/anotherviewpoint ) As most every one knows,
radiometric dating is done primarily on igneous rock. Within Grand
Canyon are several outcrops of volcanic rock, two of which I'd like to
talk about -- familiar to many who know of Grand Canyon. They are the
Cardenas Basalts of the Grand Canyon Supergroup at the bottom of Grand
Canyon and the Uinkaret plateau lava flows. These outcrops are of
interest because the Cardenas Basalts represent some of the oldest rocks
in Grand Canyon, existing below all the horizontal layers which make
Grand Canyon so famous. On the other hand, the Uinkaret Plateau lava
flows extruded on top of the plateaus above the canyon, some of which
also flowed down inside Grand Canyon. Everyone agrees that the Uinkaret
lava flows must be younger than the formation of Grand Canyon (less than
1 million years) and that Grand Canyon must be younger than the Cardenas
basalts. Ergo, the Uinkaret lava must be younger than the Cardenas basalts.
I think that most everyone also knows that when Rb/Sr radioisotope
measurements were made of these rocks, contrary to what was expected,
the Uinkaret lava flows actually measure and compute to be OLDER (~1.3
Billion years old) than the Cardenas Basalts (~1.0 Billion years old).
This is a conundrum to any geologist -- Creationist or Evolutionist. All
arguments about assumptions and justifications aside, it still remains a
fact that EVERYONE discards and rejects the Rb/Sr data for the Uinkaret
lava flows. Although the methodology and technological processes were
faithfully and precisely followed on rock samples from both sources, the
dating for the Uinkaret is rejected while dates for the Cardenas are
accepted.
This comes to my point. Just because the process of radiometric dating
is done with great precision and great care, that does not automatically
mean that the results are going to be accepted as valid. In the many
geological papers that I've read where radiometric samples have been
processed, there is usually a "discussion" about whether to accept or
reject the ages so acquired. That choice comes about through factors
other than the accuracy of the radiometric process. In the case of the
Uinkaret/Cardenas igneous rock, non-scientifically acquired data
actually takes precedence over the scientifically (technologically?)
acquired radiometric data. It is strictly observation and logic (not
scientific experiment) that shows that the Uinkaret must be younger than
the Cardenas. This fact outweighs the scientific data acquired through
the radiometric dating process.
So, Point 1 is: The acceptance or rejection of radiometrically acquired
ages for rock depends upon factors other than the science/technology of
radiometric dating. (The Uinkaret/Cardenas system is symptomatic of the
entire radiometric dating scheme).
2: The second point concerns scientific objectivity. We are given the
impression that: 1. radiometric dating is science; 2. science is
objective; therefore 3. dating of rock units using radiometric
methodology is objective science. However, as we have just seen, the
objectivity of radiometric dating is only applicable through the
methodology of sampling, processing and computing a radiometric age.
After that point, a radiometric age may be countermanded by other
important information and data. The point I want to make now is that at
the very moment that a radiometric age is rejected (or even accepted)
based on other data, the radiometric dating method immediately becomes
subject to that other information. Thus, no matter how precise the
radiometric process has been, the results are still handled
subjectively. In the case of the Uinkaret, the computed ages are
rejected because it is impossible for them to be correct. In the case of
the Cardenas, the computed ages are accepted because they agree with
what is expected.
So, Point 2 is: The dating process of rock units is subjective even when
radiometric dates are available. The radiometric dates may be accepted
or rejected depending upon other information.
3: I'll just state this point right off the bat;
Point 3 is:
1. If any rock unit is believed to be young, then any old
radiometric age is rejected, not as inaccurate, but as irrelevant.
OR,
2. A rock unit must first be thought to be of a certain age before
such an age will be applied to it.
OR,
3. A rock unit must first be thought to be old before an old age is
applied to it.
The truth of the first statement is borne out by the lava flows of the
Uinkaret. Everybody, but everybody, but EVERYBODY believes that the
Uinkaret basalts must be young, therefore the 1.3 Billion year
radiometric computed age is not inaccurate, but completely irrelevant.
The truth of the second statement is borne out by the K-Ar computed age
of the Uinkaret basalts ranging from 10,000 years to 117 million years.
Everyone knows that the Uinkaret basalts must be younger than the age of
Grand Canyon (less than 5 million years) so the age of the Uinkaret
appears relatively confirmed by the K-Ar radiometric computed ages.
The truth of the third statement is borne out by the acceptance of the
computed old ages from Rb-Sr (~1 Billion years) and K-Ar (~800 Million
years) for the Cardenas basalts which had to be in place long before the
phanerozoic rocks were deposited through which, even later, Grand Canyon
was carved. Very few have ever doubted the computed ages applied to the
Cardenas, nor even considered looking for younger dates.
Summary:
1. The acceptance or rejection of radiometrically acquired ages for
rock depends upon factors other than the science/technology of
radiometric dating.
2. The dating process of rock units is subjective even when
radiometric dates are available.
3. If any rock unit is believed to be young, then any old
radiometric age is rejected, not as inaccurate, but as irrelevant.
So where does this bring us?
I, as a Creationary Cataclysmist, consider that all igneous rock units
found within the phanerozoic (the geologic record of sedimentary rock
units containing fossil and thus must be post sin) are probably mostly
emplaced during or after the flood cataclysm. Therefore, based on
chronological evidence in the Bible, the Phanerozoic and included
igneous formations are approximately 4000 years old. Since I believe
that these igneous rocks must be very young, then all radiometrically
acquired and computed old ages are not inaccurate, but completely
irrelevant.
Within the Biblically based paradigm of Creationary Cataclysmism, old
radiometrically computed ages for igneous rock contained within the
phanerozoic record have no meaning or reality. (please note, I am not
here discussing the age of the Universe nor of a pre-creation week
planetoid that likely existed in a void state.) All such computed old
ages can be safely ignored as totally irrelevant and they have no
bearing at all in preparing flood models.
References:
Uinkaret Lava age
K/Ar date sources
0.01 million years
S. J. Reynolds, et. al. "Compilation of Radiometric Age Determinations
in Arizona," Arizona Bureau of Geology and Mineral Technology Bulletin,
197 (1986):1-258
117 million years
P.E. Damon and others, "Correlation and Chronology of the Ore Deposits
and Volcanic Rocks," U.W. Atomic Energy Commission Annual Report, No.
C00-689-76, (1967), 82 pg.
1.2 million years
E.D. McKee, Hamblin and Damon, "K-Ar Age of Lava Dam in Grand Canyon,"
GSA Bulletin, 79 (Jan. 1968):133-136.
3.67, 2.63, 3.60 million years
Renolds, et. al., op-cit. p 14, 16
Rb/Sr date sources
1.27-1.36 billion years
Austin, S. A. "Are Grand Canyon Rocks One Billion Years Old?" Grand
Canyon: Monument to Catastrophe. 1994, p. 125
Pb/Pb date sources
2.6 billion years
Renolds, et. al., op-cit.
Cardenas Basalt ages.
K/Ar date sources
853 my
Ford, Breed and Mitchell, "Name and Age of the Upp-er Precambrian
Basalts in Eastern Grand Canyon." GSA Bulletin, 83 (Jan. 1972), 223-226
820, 800, 791, 843 my
McKee and Noble, "Age of the Cardenas Lavas, Grand Canyon, AZ" GSA
bulletin, 83 (Jan, 1976):1180-1190
&
Elson and McKee, "Age and Correlation of the Late Proterozoic Grand
Canyon Disturbance, Northern Arizona" GSA Bulletin, 93 (Aug. 1982)m 681-699
Rb/Sr date sources
0.98 to 1.09 billion years
McKee and Noble, "Age of the Cardenas Lavas, Grand Canyon, AZ" GSA
bulletin, 83 (Jan, 1976):1180-1190
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