Detailed geologic mapping in the Mormon Mountains and
new geophysical data provide significant insight into
contractional and extensional tectonics in southern Nevada,
southwest Utah, and northwest Arizona. The rocks in the
region were complexly deformed during two distinct tectonic
episodes. Numerous interrelated events occurred within each
episode. The first tectonic...
The North Muddy Mountains are located in southern
Nevada, about 65 km northeast of Las Vegas and near the
eastern boundary of the Basin and Range province. The
north-south-trending range block is bounded on the east and
west, respectively, by east- and west-dipping, high-angle
normal faults. Sevier age contractional and...
Surface and subsurface data are combined to determine the structure of the western half of the Simi fault system in the Las Posas and Camarillo Hills area. Cretaceous to Eocene sedimentary rocks, present only in the subsurface, are overlain by late Eocene to early Miocene nonmarine stata (Sespe Formation) and...
The northern Los Angeles basin is influenced by two structural styles: the west-trending compressional Transverse Ranges to the north, and the strike-slip Peninsular Ranges to the south. The interaction of these two structural styles has resulted in a complex fold fault belt at the northern margin of the Los Angeles...
Subsurface mapping was used to determine the structure andgeologic history of the South Cuyama dome and part of the Russellfault in the South Cuyama oil field area. Deformed Late Cretaceousand or early Tertiary marine strata are unconformably overlain bythe late Oligocene to early Miocene Vaqueros Formation (QuailCanyon Sandstone Member, Soda...
The Santa Barbara-Montecito and Goleta basins are structurally
continuous fault-controlled Pleistocene basins containing
up to 3000 feet (925 m) of marine Pleistocene Santa Barbara Formation
which were deposited on previously deformed Sisquoc and older
strata. Structures subcropping against the unconformity at the
base of the Santa Barbara Formation show that...
Himalayan collision produced frontal and lateral
ramps and associated Pliocene to Quaternary tectonic
geomorphic features in the foreland fold-thrust belt of
northwestern Pakistan. The transpressional right-lateral
Kalabagh tear fault zone displaced the emergent Surghar
Range frontal thrust from the western Salt Range by 16-19
km since 1.9-2.1 Ma: the age...
Active faults in the Kaikoura region include the Hope,
Kekerengu, and Fidget Faults, and the newly discovered
Jordan Thrust, Fyffe, and Kowhai Faults. Ages of faulted
alluvial terraces along the Hope Fault and the Jordan
Thrust were estimated using radiocarbon-calibrated
weathering-rind measurements on graywacke clasts. Within
the study area, the...
Nine west-northwest-trending faults on the continental margin of
Oregon and Washington, between 43° 05'N and 470 20'N latitude, have been
mapped using seismic reflection, sidescan sonar, submersibles, and swath
bathymetry. Five of these oblique faults are found on both the Juan de Fuca
and North American plates, and offset abyssal...
