USGS Science⌕ Search

SEARCH · USGS Science

Results for “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 1,801 records · Page 100Linked to original sources
USGS1975

Preliminary report on the reconnaissance engineering geology of the Yakutat area, Alaska, with emphasis on evaluation of earthquake and other geologic hazards

Yakutat, situated about 225 miles northwest of Juneau, Alaska, near the shores of the Gulf of Alaska, has a setting that calls for superlatives. Within the Yakutat region are some of the tallest mountains, some of the heaviest snowfalls, and the largest glacier in North America. Between the abrupt mountain front and the Gulf of Alaska lies a very gently sloping plain of outwash derived from repeated cycles of advance followed by melt and retreat of glaciers during the Quaternary Period. The latest melting probably took place 500 to 600 years ago. Yakutat is built upon the moderately steep moraine that is the product of melting of one of these glaciers. Near Yakutat, surficial deposits are as much as 700 feet thick and probably overlie siltstone, sandstone, and mudstone. The eight general categories of mapped surficial deposits include artificial fill, organic, eolian, beach, delta-estuarine, alluvial, and outwash deposits, and deposits of the outer Yakutat Bay moraine complex.

Alaska↗
USGS1975

Interim report on petroleum resource potential and geologic hazards in the outer continental shelf of the Gulf of Alaska Tertiary province

The potential for discovering large accumulations of petroleum on the Outer Continental Shelf of the Gulf of Alaska Tertiary Province cannot be evaluated with much confidence at present because of the inadequacies of the available offshore geological and geophysical data. The 22 deep test wells that have been drilled since 1954 have been unsuccessful because structure is complex and because suitable reservoir rocks have not been found in favorable structural positions. Although it is possible that the factors controlling accumulation of petroleum may improve offshore, regional stratigraphic and structural considerations together with the limited geophysical data suggest that this is not necessarily the case. Extrapolation of onshore geology together with the limited amount of marine geophysical data, indicate that the eastern Gulf of Alaska Outer Continental Shelf is geologically complex and consists of several areas with markedly differing structural styles and petroleum potential.

Alaska↗
USGS1975

Mineral deposits in western Saudi Arabia; a preliminary report

Mineral deposits in Saudi Arabia include a variety of deposits which were formed in many geologic environments. These include magmatic and late magmatic deposits in igneous masses, contact metamorphic deposits along the margins of igneous bodies, and stratiform sulfide deposits and veins. Notable deposits of sedimentary origin include deposits of iron oxides and phosphate. Strata-bound massive sulfide deposits containing copper, zinc, and nickel sulfides associated with pyrite and pyrrhotite in complexly deformed volcanic rocks in Saudi Arabia have been the subject of controversy. They are considered by some geologists to be of syngenetic or volcanogenic origin, and by others to be epigenetic. The principal mineral deposits in western Saudi Arabia are localized in mineral belts within tectonic zones that trend northerly, northeasterly, and northwesterly. These belts contain the exploration target areas most promising for future exploration. Noteworthy among these are: 1) the northerly-trending Bidah copper-zinc belt; 2) the Sayid copper-zinc zone; 3) the northwest-trending Nuqrah copper zinc-silver belt; and 4) the north-northwesterly-trending Al Amar belt. Gold and silver deposits are mainly localized in north-trending structural features of the Hijaz geotectonic cycle and northwest Najd trends. Saudi Arabian metal deposits known thus far contain reserves in the 2 billion dollar range. Further exploration should result in discoveries that could significantly increase this amount; Saudi Arabia may well have workable metallic and nonmetallic mineral resources for industrial developments in many parts of the Kingdom. In order to effectively carry on a search for new mineral deposits, the belts should be mapped in detail, with emphasis on the delineation of stratigraphic and structural features that control metallization. In addition, geochemical and geophysical studies should be made of promising areas to outline exploration targets. These targets could then be systematically explored.

Open-File Report↗
USGS1976

Report on the environmental geology OCS area, eastern Gulf of Alaska

In anticipation of oil and gas leasing of the outer continental shelf (OCS lease area 39) in the northeastern Gulf of Alaska, the U. S. Geological Survey began a regional reconnaissance in 1974. The study area, which extends from Prince William Sound on the west to Yakutat Bay on the east, is in a region fraught with natural hazards. The tectonic history of the area suggests that future major earthquakes could pose serious hazards to installations on the continental shelf or along the coast of the Gulf of Alaska. The hazard may be either direct, by ground shaking or fault displacement, or indirect, through ground failure or generation of tsunami waves. Storm waves sometimes are responsible for ground failures, especially in areas of rapid accumulation of sediment.

Alaska↗
USGS1976

Preliminary report on coal resources of the Otter Creek EMRIA site, Powder River County, Montana

The Knoblock coal bed in the Otter Creek EMRIA (Energy Minerals Rehabilitation Inventory and Analysis) site--an area of about 1,177 acres (476 hectares)--contains estimated identified coal resources of about 126 million short tons (114 million metric tons). The area around and including the Otter Creek EMRIA slte--an area of about 2,975 acres (1,204 hectares)--contalns estimated identified coal resources of about 318 million short tons (289 million metric tons). All estimated coal resources in the Knoblock bed are categorized as measured and indicated resources, and all but about 62 million tons (56 million metric tons) are at depths of less than 200 feet (60 metres). The average thickness of the Knoblock is about 61 feet (18.6 metres) and the overall relationship of quantity of overburden to tons of coal in the area with 200 feet (60 metres) or less of overburden is about 2 cubic yards (1.5 cubic metres) of overburden per ton of coal. The coal is subbituminous C in rank, has an average sulfur content of less than 0.2 percent, and has an average ash content of about 5.5 percent. The major and minor element composition of coal, coal-ash, and rock samples from the area is similar to the average composition of other coals of the Northern Great Plains and to the average rock composition of the Earth's crust. Only the selenium content of the Knoblock coal is more than an order of magnitude higher than that in the continental crust.

Open-File Report↗
USGS1976

Analog-model analysis of effect of wastewater management on the ground-water reservoir in Nassau and Suffolk Counties, New York: Report I: Proposed and current sewerage

By 1995, the water table may fall by as much as 5 metres (16 feet) in east-central Nassau County and as much as 1.8 metres (6 feet) in central Suffolk County as a result of proposed sewerage programs. similar, but generally slightly less, change may occur in the potentiometric head in the Magothy aquifer. Streamflow may decrease by as much as 55 percent in streams draining from Nassau County Sewage Disposal District 3 and as much as 56 percent in streams draining from the Huntington-Northport Sewer District.

Open-File Report↗
USGS1976

Progress report on the development of a specific-ion logging system for uranium exploration

Substantial progress has been made in the development of a portable system for borehole logging of Eh, pH, and S in formation waters. Recent improvements in reference and pH electrode construction contributed to an improved quality of field data and permitted recognition of design deficiencies. Modification of the system has corrected these deficiencies and improved both instrument reliability and its suitability for measuring ionic activities.

Open-File Report↗

Refine your search to explore more results.