A useful, but simple, bulk indicator of the circulation is the time since water has last been at the surface, commonly known as the “age” of seawater. The observed radiocarbon activity is well-suited for determining the age, because radiocarbon is not produced in the ocean, the radioactive decay rate is known, and its half-life is in the right range. General circulation models have also been used to estimate ocean age, but while the concentration of radiocarbon produced by the models is consistent with the observational studies, the inferred ages are not.
http://www.people.fas.harvard.edu/~phuybers/Doc/radiocarbon_draft.pdf
Hi,
a good starting point about the procedure and results about the age of waters in world oceans may be a paper published by Gebbie & Huybers in Journal of Physical Oceanography, vol. 42, 291-305 (2012):
http://www.whoi.edu/fileserver.do?id=117784&pt=2&p=119089
http://www.people.fas.harvard.edu/~phuybers/Doc/radiocarbon_draft.pdf
Kind regards,
Matjaž
i hope this helps
http://www.people.fas.harvard.edu/~phuybers/Doc/radiocarbon_draft.pdf
http://www.csun.edu/~vcgeo005/collins.pdf
http://www.ldeo.columbia.edu/~spk/Papers/KhatiwalaetalAgeDSR01.pdf
http://www.delmarlearning.com/companions/content/1418065978/student_resources/Oceans/ddoe_unit1.pdf
http://puddle.mit.edu/~cwunsch/papersonline/transientracer.pdf
Best regards
Vilemar Magalhães
Dear Kamal, It is very much necessary in studies like paleography of earth features.
What about aging of water they found under a mine in Canada? They claim it is a couple of billions of years old. How do they know that there has not been infiltration from above due to tectonic activities?
No detailed information I have on mind here. But it should be part of the age of earth itself. Does/can anyone know based on educated empirical calculations?!
Paleogeographic plate rotation procedures to provide paleogeographic context to fossil collection data when their age and modern - day latitude/longitude coordinates are entered . However, these paleogeographic rotations, which derive principally from PaleoMap, are essentially static and are not well documented. Developing an infrastructure that can make use of the most current information from the active paleogeographic community, possibly using a web service - based architecture, would provide a significant service to the paleobiological community, as well as many others who require up - to - date and well documented paleogeographic context for
their data and model results/calibrations.
http://workspace.earthcube.org/sites/default/files/files/document-repository/Gurnis%20-%20Paleogeographic%20_%20Plate%20Tectonics%20Reconstructions-%20Critical%20Components%20linking%20the%20evolution%20of%20the%20solid,%20fluid%20and%20living%20Earths.pdf
A useful, but simple, bulk indicator of the circulation is the time since water has last been at the surface, commonly known as the “age” of seawater. The observed radiocarbon activity is well-suited for determining the age, because radiocarbon is not produced in the ocean, the radioactive decay rate is known, and its half-life is in the right range. General circulation models have also been used to estimate ocean age, but while the concentration of radiocarbon produced by the models is consistent with the observational studies, the inferred ages are not.
http://www.people.fas.harvard.edu/~phuybers/Doc/radiocarbon_draft.pdf
Thus, there is obviously an unverified supposition/assumption for the relationship between radiocarbon change and age given that the techniques and their verifications are rather recent and the phenomena to be investigated extremely old? When different geological layers are compared using tracers, does it reflect relative variation in age estimates or absolute values in the estimates of geological age?
Age of the oceans may be matched with the age of the land. I don't know technically.
Radioactivity will provide the answer especially carbon-14 dating technique. The half life time is known for this carbon isotope, so by collecting a species containing this element from the ocean's trough, the scientists can compare the mass of the present C-14 to the deduced mass of the parent C-14 & then calculate the age of the ocean. The literature gives estimates but if scientists repeat their experiments by collecting more samples (and there is no serious interest in that), then a more precise value could be obtained.
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