Several uranium anomalies, with concentrations of U₃0₈ that
average below 0.003 percent and reach maximums of 0.069 percent,
are associated with black, fossiliferous, pyritic parts of the Ordovician
Ledbetter Slate in northern Stevens County, Washington. The most
uraniferous parts of the slate occur in small (average of 5 by 30...
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Spirit pluton, Stevens County, Washington
AN ABSTRACT OF THE THESIS OF
Terry Edward Mitchell for the
Much uncertainty exists about the state of the oceanic and atmospheric circulation in the tropical Pacific over the last glacial cycle. Studies have been hampered by the fact that sediment cores suitable for study were concentrated in the western and eastern parts of the tropical Pacific, with little information from...
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. Hovan3, Robert A.
Pockalny4, Mitchell Lyle5, Richard W. Murray6, A. Christina Ravelo7, Samantha C. Bova8
Much uncertainty exists about the state of the oceanic and atmospheric circulation in the tropical Pacific over the last glacial cycle. Studies have been hampered by the fact that sediment cores suitable for study were concentrated in the western and eastern parts of the tropical Pacific, with little information from...
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surface seawater
property gradients
Lynch‐Stieglitz, J., Polissar, P. J., Jacobel, A. W., Hovan, S. A
The Mitchell inlier in north-central Oregon contains the largest exposure of Cretaceous marine sedimentary rocks in this region. Nearly 9,000 ft of Albian-Cenamanian rocks are exposed along the flanks of the Mitchell anticline. The Cretaceous section rests unconformably overlain by Tertiary volcanic rocks. The Cretaceous rocks have previously been divided...
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AN ABS'i C OF TidE IS OF
Stephen W. Little for the
The origin of the late pre-industrial Holocene (LPIH) increase in atmospheric methane concentrations has been much debated. Hypotheses invoking changes in solely anthropogenic sources or solely natural sources have been proposed to explain the increase in concentrations. Here two high-resolution, high-precision ice core methane concentration records from Greenland and Antarctica...
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.
References and Notes:
1. P. Forster et al., in Climate Change 2007: The Physical Science Basis
Interpretation of ice core trace gas records depends on an accurate understanding of the
processes that smooth the atmospheric signal in the firn. Much work has been done to understand the
processes affecting air transport in the open pores of the firn, but a paucity of data from air trapped...
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trapping in
polar firn
Mitchell, L. E., Buizert, C., Brook, E. J., Breton, D. J., Fegyveresi, J
The origin of the late pre-industrial Holocene (LPIH) increase in atmospheric methane concentrations has been much debated. Hypotheses invoking changes in solely anthropogenic sources or solely natural sources have been proposed to explain the increase in concentrations. Here two high-resolution, high-precision ice core methane concentration records from Greenland and Antarctica...
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Anthropogenic Contribution to the
Atmospheric Methane Budget
Logan Mitchell,* Ed Brook, James E. Lee, Christo