The Whitewater River area is located directly east of Mt. Jefferson in the Cascades of central Oregon. Approximately 90 mi2 (230 km2) were mapped (scale 1/24,000) and four new K-Ar ages and 151 major element analyses were obtained in a study of the stratigraphic
and magmatic transition from the Miocene...
The Grant Range, in east-central Nevada, is a
north-east trending range bounded on the west by a
west-dipping normal fault system. Rocks within the range
record a complex polyphase Mesozoic ductile
compressional and Cenozoic brittle extensional
deformational history. The northwestern Grant Range
exposes deformed, regionally metamorphosed and
unmetamorphosed, Cambrian to...
The southeastern Cuyama Valley is located in the southern Coast
Ranges, west of Bakersfield, California. Subsurface geologic mapping
using data from 62 prospect wells was integrated with surface mapping
to determine the depositional and deformational history of this part
of the Neogene Cuyama basin.
The northwest-trending Russell fault system was...
Gravity and seismic data obtained by the geophysical group at
Oregon State University on the R/V YAQUINA during 1969, 1971, and
1973 plus other available data over the area just west of Nicaragua
and Costa Rica indicate the tectonic complexity of the region. Gravity
measurements show negative free-air anomalies over...
Early structural influences on the Cuyama basin include Oligocene extension followed by early Miocene wrench faulting. Evidence of wrench faulting is obscured by Pleistocene thrust faulting. Detailed surface and subsurface structural analysis was used to separately examine the effects of each structural regime.
The northwest-trending, right-lateral Russell fault was the...
Over 3,000 feet of nonmarine Late Cretaceous sedimentary rocks are exposed within the northern Fish Lake Plateau. The Cretaceous
strata are overlain by over 2,000 feet of Early Tertiary nonmarine sedimentary rocks and volcanics. Landslide deposits cover over one-half of the area. The Late Cretaceous Blackhawk Formation, the oldest formation...
Magnetic, gravity and bathymetry data were collected on an extended
cruise of the R/V Yaquina in 1969. The last set of data was obtained
from those track lines leaving the Panama Basin. The area
covered is mainly the Cocos plate (Molnar and Sykes, 1969). The data
is analyzed and compared...
Rocks south of the Main Mantle Thrust (MMT) in Swat,
Pakistan consist predominantly of Precambrian to Paleozoic
granitic gneisses and metasedimentary rocks that represent
the deformed and metamorphosed northern margin of the Indian
subcontinent. In the Karakar Pass area the rocks are divisible into three lithologic units: the Swat granite...
A free-air gravity anomaly map of the area between 10°-17°N and
90°-101°W shows distinctive positive and negative anomalies which
parallel the Tehuatepec Ridge. The positive anomaly approximately
overlies the topographic expression of the ridge. On the wide continental
shelf southeast of the Gulf of Tehuantepec a positive gravity
anomaly with...
The Salt Range and Potwar Plateau of northern Pakistan are part of
the thin-skinned, active thrust system related to the ongoing collision of
the Asian and Indian continental blocks. Platform rocks and orogenic
molasse of the Indo-Pakistani shield are deformed in south-verging thrusts
and folds, relative to a northward-converging basement....