Eleven small Mesozoic plutons crop out within a 76-squaremile
area of the southern Seven Devils Mountains in west-central
Idaho. The plutons are divided into a mafic suite, an older granitic
suite, and a younger granitic suite on the basis of age, lithology, and
degree of metamorphism.
The six plutons of...
Elliptical borehole enlargements or "breakouts" caused by systematic spalling of a
borehole wall due to regional maximum horizontal stresses were identified in 18 wells
drilled in the Coast Range and Willamette Valley of western Oregon. The breakouts
generally indicate a NNW to NNE orientation of maximum horizontal compression
(oH[subscript max])...
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. Additional
funding was provided by ARCO Oil and Gas Company and the Peter P. Johnsen
scholarship committee
Castle Rocks is 12 miles east of Mt. Jefferson, in the central
Cascades of Oregon. The area contains volcanic rocks ranging from
mid-Miocene to Holocene in age. These rocks record alternating
periods of tholeiitic and calc-alkaline volcanism.
The oldest rocks in the area range from basaltic andesite lava
flows to...
Declining abundance of Chinook Salmon Oncorhynchus tshawytscha across the Pacific Northwest is an issue of
great concern ecologically, culturally, and economically. Growth during the first summer is vitally important for
juvenile Chinook Salmon, as it influences not only life history decisions (to smolt or not to smolt) but also subsequent...
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(Dunham et al. 2002; Peter-
son et al. 2004). Finally, juvenile salmon of hatchery origin are
an
The identification and mapping of surface cover types
within Crater Lake National Park, Oregon, has been effectively
completed through the utilization of LANDSAT digital
data and NASA U-2 color infrared aerial photography. Classification
of LANDSAT data for surface cover type identification
and mapping was accomplished through use of the
Interactive...
Ocean acidification is a global, long-term problem whose ultimate solution requires carbon dioxide reduction at a scope and
scale that will take decades to accomplish successfully. Until that is achieved, feasible and locally relevant adaptation and
mitigation measures are needed. To help to prioritize societal responses to ocean acidification, we...
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Rittschof8, Carolyn Doherty8,
Peter E. T. Edwards15,16 and Rosimeiry Portela17
Ocean acidification is a
Formation of cirrus clouds depends on the availability of ice nuclei to begin condensation of atmospheric water vapor. Although it is known that only a small fraction of atmospheric aerosols are efficient ice nuclei, the critical ingredients that make those aerosols so effective have not been established. We have determined...
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Academic,
Dordrecht, ed. 2, 1997), pp. 309–354.
5. T. Koop, B. P. Luo, A. Tsias, T. Peter, Water