| Earth science (27) |  |
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"Ten years from now, this is going to be like radiocarbon dating, Â says Fisher, referring to a standard technique now used by all archaeologists to date finds."
In their new study Uno and his team tested the radiocarbon dating technique on the tusks of two elephants that died in 2006 and 2008 as well as elephant and hippo teeth monkey hair and oryx horn.
and Uno are also using the radiocarbon dating technique to investigate the growth rate of animals. Now that we can determine growth rates in teeth we can use them as a tape recorder of sorts Uno said.
Wasser envisioned the carbon-14 dating technique being useful in a variety of ways. For example if used in combination with other methods that use DNA to determine the geographical origin of an ivory sample the carbon-14 dating technique could help investigators determine how recently hotspots for elephant poaching have been active.
Also if the ivory in a large seizure included samples of multiple ages it might suggest that the ivory was obtained from government stockpiles
Abdalati is currently director of the Earth science and Observation Center at the University of Colorado at Boulder.
since the late Jurassic when it was about 2500 ppm vs today's 400 ppm.
and millions of years. just 10000 years ago we were in the Pleistocene. A climate era of 10x the natural variance of the Holocene (think global temperature changes of 1. 5 C per decade rather than per century.
If you look back 2 to 3 million years you find a heightened period of CO2
This is less helpful in dating on more geological time scales but the various radiometric dating techniques used on those scales have other means of control
For this reason radiocarbon dating only works for organisms that obtain their carbon from air via carbon dioxide.
my guess as to the reason why is that carbon-14 dating is quite expensive and the purpose of the record is actually to help calibrate radiocarbon dating
so they didn't need to have annual resolution). Over the past 3000 years there have been 3 sharp spikes in carbon-14 levels over a short period of time.
Also@monkeybuttons while it's true that carbon-14 dating isn't perfectly precise this study was based on tree rings
and then build a calibration curve to make radiocarbon dating more accurate. Before 12000 years that record consists of data from marine sediments.
and Cheirolepidiaceae--a now-extinct family of conifers known only from the Mesozoic. This tells us that 150 million years ago the ancient forests of western North america consisted of members of these three families.
United states 517-432-4412 rosejo@msu. edulinking advances in genomics research mathematics and earth sciences as well as novel engineering technologies is imperative
And as such the Athropocene the age of humans is proposed the term for our current geological time scale,
marking the end of the Holocene about 200 years ago. If technological innovation brought humans to a population of 7 billion can it also make the future planet livable?
are worried we enough about saving human civilization to make this time scale, the Anthropocene, more than a mere speck in the geologic time scale?
the Holocene, may have come to a close, and we humans where the â Å anthro â Â part of the name comes from may be largely responsible for the shift.
The Holocene got its start when the last ice age ended and we shifted from a glacial ice covering much of the northern hemisphere,
which was the end of the Pleistocene. The Holocene may have ended when James Watt invented his steam engine.
And we started pumping out CO2 by burning coal. So in addition to the climate change we have raised greenhouse gasses in the atmosphere by about 100 parts per million (ppm)
That is a huge change compared to only a third of the Earth surface was covered by ice at the end of the Pleistocene and the shift into the Holocene,
We are putting carbon that was locked away during the Cretaceous period 300 million years ago, back into the atmosphere as CO2.
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