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...
The goal of this study was to advance methods for assessment of forest road hydrologic
response and sediment yield at a catchment scale. This research looked at the effect of
soil depth estimation on the Distributive Hydrology Soil Vegetation Model (DHSVM),
assessed the uncertainty and accuracy of hydrologic modeling of...
New data are presented that provide evidence for the onset of extensional deformation in the Northwestern Basin and Range within 1 million years after the eruption of the Steens Basalt at 16.5 Ma. New geologic mapping (1:24,000), stratigraphic sections, and ⁴⁰Ar/³⁹Ar dating of the Crane Basin rocks provide a control...
The present bibliography is the third compilation by the Oregon Department of Geology and Mineral Industries (DOGAMI) of theses and dissertations containing information on the geology of the state. It follows and incorporates the Bibliography of Theses on Oregon Geology by H.G. Schlicker (DOGAMI Miscellaneous Paper 7, 1959) and the...
The thesis area is located in the southeastern corner of Harney County, Oregon. This portion of Oregon is situated in the northern part of the Basin and Range province, and is characterized by both mafic and silicic extrusives, and localized nonmarine sediments and
tuffs ranging in age from middle (?)...
Bedrock groundwater dynamics in headwater catchments are poorly understood and
poorly characterized. Direct hydrometric measurements have been limited due to the
logistical challenges associated with drilling through hard rock in steep, remote and
often roadless terrain. Here we develop and use an inexpensive, portable bedrock
drilling system to explore bedrock...
Our studies and those of our colleagues in Idaho indicate that the western Snake River Basin is a major geothermal province, similar in some ways to the Imperial Valley Geothermal Province. Deep drilling should encounter high temperature fluids in permeable rocks below 2 km and at shallower depths where permeability...
Wright's Point, a 250-foot-high, sinuous, flat-topped ridge, projects eastward into Harney Basin, Harney County, Oregon. This 6-mile-long feature ranges from 200 to 600 yards wide and merges with a broad mesa at its western end. The nearest topographic highs are Dog Mountain, 2 miles southwest, and foothills of the Blue...
(1) Field mapping and biostratigraphic data indicate that the Yamhill Formation overlies and is younger than the Tyee Formation; interfingering of the two formations is not indicated. (2) Stewart's correlation of the Yamhill Formation with the Sacchi Beach member of the Tyee was based on incomplete knowledge of the range...
The Oregon coast between Yaquina Head and Government Point owes its scenic grandeur to a unique wedding of ancient and recent marine environments. Visitors to Beverly Beach State Park, located in the southern part of this coastal strip, have a rare opportunity to wander along a shoreline that some 15...
When you drive through the Madras region on U.S. Highway 97, you see a gently rolling plain dotted with low hills and flat-topped buttes. Since the plain appears to extend westward uninterruptedly to the foothills of the Cascade Range, little would you imagine that between you and the mountains lurk...
Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic,...
This report summarizes results of geologic mapping in the South Umpqua Falls region of the Western Cascade Range in Douglas County, southwestern Oregon (plate 1). Rocks of the Western Cascades range in age from late Eocene to late Miocene and consist of deformed and partially altered flows, pyroclastic rocks, and...
The stacks off the southern Oregon coast have been studied very little because of difficulties of access (see, for example, Weissenborn and Snavely, 1968). Work described herein was helicopter-supported; skillful piloting by Earl Lady permitted landings on or close approaches to many stacks. To help delineate the structure, field work...
This field trip consists of two geologic tours. On Tour 1, the Tertiary sedimentary rocks exposed along the Yaquina River between Newport and Toledo, Oregon, will be examined. This tour will start at the mouth of Yaquina Bay where Miocene sedimentary rocks are exposed and will proceed generally eastward and...