Silicic volcanism in the central Oregon Cascade range has decreased in both the size and frequency of eruptions from its initiation at ~40 Ma to present. The reasons for this reduction in silicic volcanism are poorly constrained. Studies of the petrogenesis of these magmas have the potential for addressing this...
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High Cascade Silicic Volcanism: Analysis of the Lower Bridge and McKenzie Canyon Tuff
by Daniel W
Silicic volcanism in the central Oregon Cascade range has decreased in both the size and frequency of eruptions from its initiation at ~40 Ma to present. The reasons for this reduction in silicic volcanism are poorly constrained. Studies of the petrogenesis of these magmas have the potential for addressing this...
Full Text:
Cascade Silicic Volcanism: Analysis of the McKenzie Canyon and
Lower Bridge Tuff
Abstract
Volcanic and sedimentary deposits of the Mount Jefferson area (MJA) record a fourmillion-year
history of arc-related volcanism related to the subduction of the Juan de Fuca plate
beneath North America. 171 mapped stratigraphic units over an area of 150 km² reveal four
periods of volcanic activity resulting in diverse composition...
Volcanic and sedimentary deposits of the Mount Jefferson area (MJA) record a fourmillion-year
history of arc-related volcanism related to the subduction of the Juan de Fuca plate
beneath North America. 171 mapped stratigraphic units over an area of 150 km² reveal four
periods of volcanic activity resulting in diverse composition...
It is obvious to anyone who reads about or buys anything in the United States that we have a productivity problem. Losing our share of world markets, runaway inflation, high interest and unemployment rates are just a few of the symptoms. At Boise Cascade, we are very concerned about our...
Published May 1993. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral arc hosts a series of small plutons that are locally associated with porphyry (Cu-Mo) and epithermal (Au) ore deposits. Three...
The volcanic (~45-10 Ma) and plutonic rocks (~37-12 Ma) comprising the Western Cascades extend from northernmost California to southern British Columbia and are ancestral to modern arc magmatism. The ancestral arc hosts a series of small plutons that are locally associated with porphyry (Cu-Mo) and epithermal (Au) ore deposits. Three...
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evidence
that
Western
Cascade
magmas
were
strongly
oxidized
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NNO
+1
The Forest Elevation Snow Transect (ForEST) project is a paired site elevational snow study. It is designed to measure how snow accumulates and ablates under different forest structures across an elevation range. The ForEST project has been ongoing since the winter of 2011-2012 within the McKenzie River Basin of the...