The volcanic rocks of the Harney Basin comprise a bimodal
assemblage of rhyolites (SiO₂ greater than 72%) and basalts (SiO₂
less than 52%). Tholeiitic basalts account for 15 rocks analyzed and
alkalic basalts for three. Most basalts contain phenocrysts of olivine
and plagioclase. Pyroxene phenocrysts were not found. Rhyolite
flows...
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Plateau
The area of study is at the eastern extension of the Cascades-
High Lava Plateau physiographic
The Ventura basin is an elongate sedimentary trough extending from the San Gabriel fault west into the Santa
Barbara Channel. West of Ventura it contains over 4 km of severely deformed Pliocene and Pleistocene clastic
strata. The north-dipping Red Mountain reverse fault system, which forms the northern boundary of the...
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western extension of the Ventura Avenue anticline.
Both anticlines formed approximately 200,000 years ago
Twelve earthquakes off the Oregon and Northern California
coasts were used in this research to study whether faulting associated
with these quakes was of the San Andreas type as observed in
California. The first motions of the incident P and S waves recorded
at various seismic stations in the Pacific...
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Oregon and Northern California which appear to be along a
seaward extension of the San Andreas fault
Oregon’s High Lava Plains Province (HLP) has strongly bimodal basalt and rhyolitic volcanism. The Province caps the northern margin of the Basin and Range Province and serves as a transitional region between westward extension of the Basin and Range Province and unextended crust to the north . The High Lava...
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transitional region between westward extension of the Basin
and Range Province and unextended crust to the
Floods and ensuing damage have always been a problem for man.
Initial reaction to the frequent destruction was to avoid siting
permanent domiciles on flood-prone lands. As a result of increasing
population and pressure for development, flood control structures
were built. Instead of reducing flood losses, however, flood control
projects...
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and H. 13827
Extension of Certain Laws Relating to
Housing, Banking, and Urban Develop-
ment
S.J
This study utilizes a multidisciplinary research approach integrating the sciences of archaeology, geology, pedology and paleoclimatology. Deeply stratified and radiocarbon dated sedimentary sequences spanning the last 10,000 yr B.P. are reported for the Cremer site (24SW264), south-central Montana. Previous investigations at the site revealed an archaeological assemblage with Early Plains...
Obtaining accurate estimates of animal abundance is made difficult by the fact that most
animal species are detected imperfectly. Early attempts at building likelihood models that
account for unknown detection probability impose a simplifying assumption unrealistic for
many populations, however: no births, deaths, migration or emigration can occur in the...
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an extension of the closed population models of MacKenzie et al. (2002) and Tyre et al.
(2003). It