Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Open-File Report”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
USGS1978

Water resources of No Name Valley, Colville Indian Reservation, Washington

No Name Creek valley is a trough cut in granitic bedrock in north-central Washington. A low topographic divide in the northern third of the valley separates it into the No Name Creek basin on the south and Omak Creek basin on the north. Omak Creek is the larger stream and enters the valley through a narrow gorge in the eastern granite wall. Partly filled with unconsolidated sand, gravel, and silt to depths as great as 163 feet, the valley contains a ground-water reservoir which supplies four irrigation wells and several domestic-supply wells. The ground-water reservoir also feeds springs which give rise to No Name Creek, and it contributes some water to Omak Creek to the north. Under conditions of the pre-1976 development the ground-water divide was naturally about 3,000 feet north of Omak Creek gorge, and about 580 acre-feet of leakage from Omak Creek recharges the No Name Creek ground-water reservoir. By 1977, ground-water withdrawal of 994 acre-feet per year in No Name Creek basin had caused the ground-water divide to shift to a position about 4,000 feet north of the topographic divide. This increased the drainage area contributing to the No Name Creek ground-water reservoir for about three months so that during a year of normal flow a total of about 600 acre-feet of leakage from Omak Creek can be captured. It is postulated that as much as 1,100 acre-feet per year can be pumped in the central part of the reservoir. This pumpage would cause the ground-water divide to shift farther north, resulting in the capture of additional recharge from Omak Creek; the total leakage would be about 700 acre-feet per year. (Woodard-USGS)

Open-File Report↗
USGS1978

Erosion, sediment discharge, and channel morphology in the Upper Chattahoochee River basin, Georgia

Average annual rates of sheet erosion and sediment discharge were computed for several watersheds in the Upper Chattahoochee River basin in Georgia. Erosion yields ranged from about 900 to 6,000 tons per year per square mile in nine watersheds and were greatest where land use is largely agricultural or transitional. Suspended sediment yields from the same watershed ranged from about 300 to 800 tons per year per square mile and were greatest from urban areas and least from mostly forested watersheds. The impact of suspended sediment on stream quality was evaluated for 14 watersheds. In general, 60 percent or more of the total annual discharge of trace metals and phosphorus was contributed by suspended sediment. Yields of trace metals and nutrients in suspension were consistently greater in urban watersheds. Turbidity in basin streams increased geometrically with increasing concentrations of suspended sediment. (Woodard-USGS)

Georgia↗
USGS1978

Ages of flow units in the far eastern lunar maria based on crater density

The distribution of major geologic units of uniform relative age exposed in the far eastern maria (i.e., Mare Marginis, Mare Smythii, and Mare Crisium) and Mare Humorum was compiled in map form on the basis of a crater density mapping technique. Correlation of crater densities and radiometric ages of Apollo landing sites provide estimates of the absolute age for the units. Results indicate that the far eastern maria were emplaced over a period of approximately 1.25 b.y., from about 3.75 b.y. to 2.5 b.y. before present. Extensive young mare units (~ 2.5 ± 0.5 b.y.) occur in all three large far eastern maria. Major old units (~ 3.65 ± 0.05 b.y.) occur in central Mare Crisium and eastern Mare Marginis. Correlation of the age data and remote sensing data suggests that: (1) both young and old units have relatively high Mg/A1 ratios and are relatively rich in Fe and Ti, whereas intermediate age units have lower Mg/Al ratios and less Fe and Ti. A similar relationship previously noted for other maria suggests that this applied throughout the lunar maria; (2) older units generally have higher remnant magnetism than younger units - a relationship also previously noted for other lunar maria and attributed to a steady decline of a primodial lunar magnetic field, and (3) all age units in the eastern maria have relatively low natural radioactivity or abundances of Th, K, and U compared to the western maria (particularly in the Mare Imbrium area). The presence of young lava flows in both the eastern and western maria suggests that the relative abundance of these radioactive elements has played only a minor role in controlling the duration and location of mare volcanism. The crater-density relative age data presented here correlate in a linear fashion with crater-morphology relative age data. A combination of these data provides a nearly complete map of the distribution of units of uniform relative age of the lunar maria and shows that, as previously suggested, the older units (> 3.5 b.y. old) are generally located along the basin edges and the younger units (< 3.5 b.y. old) are generally in the basin centers. However, this map also shows that the vents for the flows of the young units must be located on the edges of the basins. These observations support tectonic models of basin subsidence caused by isostatic adjustment to the weight of the lava and to subsurface evacuation and subsequent collapse as the lavas were erupted.

Open-File Report↗
USGS1978

Reconnaissance evaluation of water resources for hydraulic coal mining, Grand Hogback coal field: Garfield and Rio Blanco Counties, Colorado

Surface-water and ground-water data were compiled for the parts of the Colorado River and the White River basins in and adjacent to the Grand Hogback coal field. The data were evaluated to assess the quantity and quality of water resources available in the area for use in hydraulic coal mining. Based on discharge records, surface-water supplies of most streams should be adequate to meet the demands for hydraulic mining of 1 million tons of coal per year with a recycled water system. However, on some of the smaller streams in the area, some storage of water may be required for use during low-flow periods to meet minimum-flow requirements for downstream reaches. Other potential sources of water include Rifle Gap Reservoir, Harvey Gap Reservoir, and ground water from valley-fill deposits along major streams and rivers. The surface water and ground water should be of adequate quality for use in hydraulic mining, with the possible exceptions of suspended-sediment concentrations that periodically may be as much as 18,800 milligrams per liter in streams in the Rifle Creek drainage, and dissolved-solids concentrations greater than 20,000 milligrams per liter in some aquifers. Data are insufficient to assess the potential impact of hydraulic coal mining on downstream water quality. (Woodard-USGS)

Open-File Report↗
USGS1978

Reconnaissance evaluation of water resources for hydraulic coal mining, Crested Butte coal field, Gunnison County, Colorado

Available surface-water and ground-water data were compiled for the parts of the Gunnison River basin in and adjacent to the Crested Butte coal field. The data were evaluated to assess the quantity and quality of water resources in the area for use in hydraulic coal mining. Based on discharge records, surface-water supplies of most streams should be adequate to meet the demands for hydraulic mining of 1 million tons of coal per year with a recycled water system. However, on some of the smaller streams in the area, some storage of water may be required for use during low-flow periods to meet minimum-flow requirements for downstream reaches. Ground water from alluvium along major streams and rivers and, in certain parts of the study area, from the Dakota and Entrada Sandstones, is also a potential source of water for hydraulic coal mining. The surface and ground water in the study area should be of adequate quality for use in hydraulic coal mining, with the possible exception of Coal Creek which has excessive concentrations of iron, manganese, and zinc. Data are insufficient to assess the potential impact of hydraulic coal mining on downstream water quality.

Colorado↗
USGS1979

Preliminary results of the Sabkhah Hazawza gravity project, Wadi as Sirhan area, Kingdom of Saudi Arabia

One hundred thirty seven new gravity stations at an average station density of one station per 17.5 km2 have been established in a 40 x 60 km area centered on Sabkhah Hazawza in the northwestern part of the Kingdom of Saudi Arabia. A successful tie to existing Arabian American Oil Co. (ARAMCO) gravity data was made and a simple Bouguer gravity anomaly map was compiled during the survey. The map shows a distinct gravity low of about -8 mgal associated with the sabkhah, its minimum displaced to the northeast of the longitudinal axis of the sabkhah. However, the continuation of the gravity anomaly under the basalt field to the northeast suggests that the gravity anomaly is due to an older basin-like structure. If the sabkhah deposits are due to damming of ancient Wadi as Sirhan by basalt flows, then the deposits are probably thin. Preliminary estimates give a maximum thickness of about 270 m for the sedimentary fill causing the gravity anomaly.

Wadi as Sirhan area↗