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Full-Text Articles in Physical Sciences and Mathematics
Discovery Of A Nanodiamond-Rich Layer In The Greenland Ice Sheet, Andrei V. Kurbatov, Paul Andrew Mayewski, Jorgen P. Steffensen, Allen West, Douglas J. Kennett, James P. Kennett, Ted E. Bunch, Mike Handley, Douglas S. Introne, Shane S. Que Hee, Christopher Mercer, Marilee Sellers, Feng Shen, Sharon B. Sneed, James C. Weaver, James H. Wittke, Thomas W. Stafford, John J. Donovan, Sujing Xie, Joshua J. Razink, Adrienne Stich, Charles R. Kinzie, Wendy S. Wolbach
Discovery Of A Nanodiamond-Rich Layer In The Greenland Ice Sheet, Andrei V. Kurbatov, Paul Andrew Mayewski, Jorgen P. Steffensen, Allen West, Douglas J. Kennett, James P. Kennett, Ted E. Bunch, Mike Handley, Douglas S. Introne, Shane S. Que Hee, Christopher Mercer, Marilee Sellers, Feng Shen, Sharon B. Sneed, James C. Weaver, James H. Wittke, Thomas W. Stafford, John J. Donovan, Sujing Xie, Joshua J. Razink, Adrienne Stich, Charles R. Kinzie, Wendy S. Wolbach
Earth Science Faculty Scholarship
We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5!106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or …
The Most Extensive Holocene Advance In The Stauning Alper, East Greenland, Occurred In The Little Ice Age, Brenda L. Hall, Carlo Baroni, George H. Denton
The Most Extensive Holocene Advance In The Stauning Alper, East Greenland, Occurred In The Little Ice Age, Brenda L. Hall, Carlo Baroni, George H. Denton
Earth Science Faculty Scholarship
We present glacial geologic and chronologic data concerning the Holocene ice extent in the Stauning Alper of East Greenland. The retreat of ice from the late-glacial position back into the mountains was accomplished by at least 11 000 cal years B.P. The only recorded advance after this time occurred during the past few centuries (the Little Ice Age). Therefore, we postulate that the Little Ice Age event represents the maximum Holocene ice extent in this part of East Greenland.
Boron-Bearing Kornerupine From Fiskenaesset, West Greenland: A Reexamination Of Specimens From The Type Locality, Edward S. Grew, Richard K. Herd, Nicholas Marquez
Boron-Bearing Kornerupine From Fiskenaesset, West Greenland: A Reexamination Of Specimens From The Type Locality, Edward S. Grew, Richard K. Herd, Nicholas Marquez
Earth Science Faculty Scholarship
In 1884, Lorenzen proposed the formula MgAI2SiO6 for his new mineral kornerupine from Fiskenæsset and did not suspect it to contain boron. Lacroix and de Gramont (1919) reported boron in Fiskenæsset kornerupine, while Herd (1973) found none. New analyses (ion microprobe mass analyser and spectrophotometric) of kornerupine in three specimens from the type locality, including the specimens analysed by Lorenzen and Herd, indicate the presence of boron in all three, in amounts ranging from 0.50 to 1.44 wt.% B203, e.g. (Li0.04 Na0.01 Ca0.01) (Mg3.49 Mn0.01 Fe0.17 …