RE: [asa] radiometric question

Would you use a truck scale to measure your own weight? It helps to have an
idea of the scale for any measuring to be effective. Other methods can be
used to get that idea, superposition, dendrochronolgy, etc.

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  -----Original Message-----
  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu]On
Behalf Of Dehler, Bernie
  Sent: Wednesday, November 05, 2008 10:38 AM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question

  Thanks for the link- just read it.

  That seems to me like they know the date they are looking for, and then
try various techniques to see how possible it is to get close to it. The
key is to know the answer to start with. If some techniques and measuring
processes were way off- they discard them and learn from the exercise. This
is so different from starting with a rock of unknown age and origin and
trying to date it. It looks to me like there may be a problem with
scientists overstating their competency, which then gives the YEC’s an
opening to exploit.

  ,,,Bernie

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  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of George Cooper
  Sent: Tuesday, November 04, 2008 2:59 PM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question
  Yes, and that seems to be the case.  My Google science effort found this:
  http://ysgeo.yonsei.ac.kr/abstractII/A0421601018.html
  This paper, apparently, demonstrates the U-Th/He system is accurate in the
few thousand years age range.
  Coope
  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of Dehler, Bernie
  Sent: Tuesday, November 04, 2008 4:01 PM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question
  “The NAiG site mentions that the testing lab used by ICR is no longer
doing K-Ar and, apparently, were clear that the tests were only accurate if
the samples were not younger than 2 million years.”
  Yes- but if you come across a volcanoe, how do you know if it is 300 or
300 million years old?  If under 6,000 years old, then the test is no good,
according to the link.  I’m thinking there are other radiometric tests to
use, but the article didn’t seem to mention that.  What would be nice to see
is if they said  “We took a sample from Mt. St. Helens and used a variety of
tests and could determine the age correctly.  The K-Ar test was
out-of-bounds as we expected.”
  …Bernie
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  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of George Cooper
  Sent: Tuesday, November 04, 2008 12:42 PM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question
  Hi Bernie,
  The site, keep in mind, is on the opposite end of the theological
spectrum, which is one reason I thought it might be of interest since it
digs a little deeper into the possible role of the ICR players.   They do a
fair job of pointing out why there is error in assuming that K-Ar (1.26
billion year half-life) would work at all with the Mt. St. Helen’s samples,
but you’ll have to do better than me to get an accurate view of this.
Admittedly, the test does appear to be a common one for igneous rock tests,
which is obviously important for volcanic sampling.
  The NAiG site mentions that the testing lab used by ICR is no longer doing
K-Ar and, apparently, were clear that the tests were only accurate if the
samples were not younger than 2 million years.   K-Ar is for dating the
oldest things, not the youngest.
  I’m just no qualified to give a fair answer to your question, but others
here can, I’m confident.
  Coope
  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of Dehler, Bernie
  Sent: Tuesday, November 04, 2008 2:03 PM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question
  Hi Coope- that was an interesting link.  I read something in that link
that wasn’t clear to me, though.  I could see a YEC saying that we weren’t
there when many volcanoes erupted, so let’s pretend we didn’t know when Mt.
St. Helens erupted and see what the radiometric results reveal.  Your link
said this:
  Without properly referencing Bartelt et al.'s report, Swenson comments on
one of the many criticisms of Austin's 'research':
  'One critic said that Dr Austin should not have sent young samples to the
dating laboratory because it potentially puts "large error-bars on the
data." By this reasoning, the method could not be used on any rocks, since,
if we did not see the rocks form, how would we know whether they are young?'
   This is the old YEC 'only eyewitnesses can provide accurate histories'
scam.  Obviously, Swenson, like many YECs, fails to realize that scientists
can successfully unravel past events without witnessing them.  Forensic
scientists frequently send criminals to prison without eyewitness testimony.
To be exact, the recent hideous actions of the Washington DC area (USA)
sniper(s) illustrate how unreliable eyewitnesses can be and how important
forensic science is in solving crimes and stopping killers.
  I don’t think the answer was very good… or the analogy of forensic
science.  For example, I guess if Mt. St. Helens had erupted 300 years ago-
before our written history, we would get back very wrong old dates, correct?
So in this case, we only know it is incorrect because we actually know when
Mt. St. Helens erupted?
  In another post response Dr. Campbell said:
  “For example I know exactly what living mollusks would be very likely to
give very old shells and modern bodies or vice versa with 14C.  If a land
snail lives on old limestone rocks, it's going to get a significant amount
of the carbonate for the shell from the rock, and it will be old relative to
the body.  Mollusks that feed on chemosynthetic bacteria that use old
hydrocarbons as an energy source are going to have old carbon in their
bodies, but form the shell from reasonably modern carbonate in seawater.“
  If you are trying to date the shells from animals that lived a few hundred
or thousand years ago, how would you know their environment?  There’s no way
to know what they fed on way back then, correct?
  …Bernie
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  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of George Cooper
  Sent: Tuesday, November 04, 2008 10:27 AM
  To: asa@calvin.edu
  Subject: RE: [asa] radiometric question
  Bernie,
  You might enjoy this site regarding the K-Ar testing of Mt. St. Helens.
  http://www.noanswersingenesis.org.au/mt_st_helens_dacite_kh.htm
  Coope
  From: asa-owner@lists.calvin.edu [mailto:asa-owner@lists.calvin.edu] On
Behalf Of Dehler, Bernie
  Sent: Tuesday, November 04, 2008 11:36 AM
  To: asa@calvin.edu
  Subject: [asa] radiometric question
  I went to talk origins to learn about radiometric dating, and was happy to
see it referred to this ASA article:
  “Radiometric Dating  -  A Christian Perspective“
  http://www.asa3.org/ASA/resources/Wiens.html
  I have a question.  It says:
  14. A young-Earth research group reported that they sent a rock erupted in
1980 from Mount Saint Helens volcano to a dating lab and got back a
potassium-argon age of several million years. This shows we should not trust
radiometric dating.
  There are indeed ways to "trick" radiometric dating if a single dating
method is improperly used on a sample. Anyone can move the hands on a clock
and get the wrong time. Likewise, people actively looking for incorrect
radiometric dates can in fact get them. Geologists have known for over forty
years that the potassium-argon method cannot be used on rocks only twenty to
thirty years old. Publicizing this incorrect age as a completely new finding
was inappropriate. The reasons are discussed in the Potassium-Argon Dating
section above. Be assured that multiple dating methods used together on
igneous rocks are almost always correct unless the sample is too difficult
to date due to factors such as metamorphism or a large fraction of
xenoliths.
  Let me ask a clarifying question.  Suppose a YEC takes a rock from Mt. St.
Helen’s and asks for a date due to radiometric dating.  I assume various
dating methods will be used… will they get the correct recent date?  I didn’
t see a clear, blunt, answer.
  …Bernie
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