Philip Dei
Sat, Jul-05-03, 18:22
Article originally posted by Mikey Brass in PaleoAnthro.
July 2, 2003, 10:11AM ROCK OF AGES Method developed at A&M
challenges claims over cave paintings By ERIC BERGER Copyright
2003 Houston Chronicle Science Writer
" Brazilian scientists recently used this method for
setting the age of several Pedra Furada paintings at
between 27,000 and 44,000 years old, backing Guidon's claim
of a very old site.
To add validity to the findings, however, the Guidon team sent
material to Marvin Rowe, a professor of archaeological
chemistry at Texas A&M University, who has developed a novel
method of dating cave art called plasma extraction.
Rowe's method is unique because he can extract traces of
carbon within the non-living pigments, giving scientists a
potentially powerful new tool to date cave painting.
In his lab, Rowe tested 12 mostly reddish paint samples and
found ages ranging from 1,230 to 3,730 years ago, hardly
eyebrow-raising dates for human habitation in South America.
"I was so disappointed myself because it would really have
been a fantastic result," Rowe said.
Guidon did not accept the results, Rowe said.
Guidon was at the research site and unavailable for comment.
But the physics professor who performed the dating for Guidon,
Shigueo Watanabe of the University of São Paulo, said he
stands by the older dates. In an e-mail, Watanabe said he is
flying this week to Pedra Furada to obtain a new sample of the
calcium found in another area to date it.
He points out that there has been little independent
verification of Rowe's technique.
Human occupation at Pedra Furada 30,000 years ago, let alone
50,000, would shatter scientific theories of the peopling of
the Americas. "
July 2, 2003, 10:11AM ROCK OF AGES Method developed at A&M
challenges claims over cave paintings By ERIC BERGER Copyright
2003 Houston Chronicle Science Writer
" Brazilian scientists recently used this method for
setting the age of several Pedra Furada paintings at
between 27,000 and 44,000 years old, backing Guidon's claim
of a very old site.
To add validity to the findings, however, the Guidon team sent
material to Marvin Rowe, a professor of archaeological
chemistry at Texas A&M University, who has developed a novel
method of dating cave art called plasma extraction.
Rowe's method is unique because he can extract traces of
carbon within the non-living pigments, giving scientists a
potentially powerful new tool to date cave painting.
In his lab, Rowe tested 12 mostly reddish paint samples and
found ages ranging from 1,230 to 3,730 years ago, hardly
eyebrow-raising dates for human habitation in South America.
"I was so disappointed myself because it would really have
been a fantastic result," Rowe said.
Guidon did not accept the results, Rowe said.
Guidon was at the research site and unavailable for comment.
But the physics professor who performed the dating for Guidon,
Shigueo Watanabe of the University of São Paulo, said he
stands by the older dates. In an e-mail, Watanabe said he is
flying this week to Pedra Furada to obtain a new sample of the
calcium found in another area to date it.
He points out that there has been little independent
verification of Rowe's technique.
Human occupation at Pedra Furada 30,000 years ago, let alone
50,000, would shatter scientific theories of the peopling of
the Americas. "