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 1,765 records · Page 98Linked to original sources
USGS1972

An evaluation of the use of drillers' logs in lithologic studies of the Ogallala Formation of the southern high plains of Texas, progress report, 1970-71

Logs made by water-well drillers were analyzed in conjunction with test-hole drilling and geophysical logging to evaluate usefulness of the driller's log in delineating areas that would be suitable for artificial recharge of the Ogallala Formation. This preliminary study indicates that lack of detailed and accurate information in many drillers' logs prevents their use as a reliable source of lithologic information. For many applications, such as evaluation of potential areas for artificial recharge, the value of more complete and more accurate information will be readily apparent as these applications become more widespread. More effort will be required in collecting lithologic information as part of the drilling operations.

Texas↗
USGS1973

Interagency Report: Astrogeology 58, television cartography

The purpose of this paper is to illustrate the processing of digital television pictures into base maps. In this context, a base map is defined as a pictorial representation of planetary surface morphology accurately reproduced on standard map projections. Topographic contour lines, albedo or geologic overprints may be super imposed on these base maps. The compilation of geodetic map controls, the techniques of mosaic compilation, computer processing and airbrush enhancement, and the compilation of con tour lines are discussed elsewhere by the originators of these techniques. A bibliography of applicable literature is included for readers interested in more detailed discussions.

Open-File Report↗
USGS1973

Preliminary report on land-surface subsidence in the area of Burnett, Scott, and Crystal Bays near Baytown, Texas

Removal of water, oil, and gas from the subsurface in Harris County has caused declines in fluid pressures which in turn have resulted in subsidence of the land surface. One critical area of subsidence is in the area of Burnett, Scott, and Crystal Bays near Baytown. Much of this area is now subject to inundation by high tides. Production of oil and gas from the Goose Creek Field at the southern edge of Baytown had caused as much as 3.25 feet of subsidence by 1925. The subsidence bowl is restricted to the area of production and has not extended to the area of Burnett, Scott, and Crystal Bays. Withdrawals of water from large-capacity industrial wells, which resulted in declines in artesian pressure, began about 1918; as much as 250 feet of water-pressure decline has occurred in the Evangeline aquifer, Significant subsidence of the land surface probably began about 1920 or later. Possibly as much as 7.5 feet of subsidence had occurred in the area by 1971. The study of subsidence in the area of the three bays included the collection of undisturbed clay samples for laboratory analyses, collection of water-level records, and installation and monitoring of pressure transducers in clays and of observation wells in sands. Probable future subsidence was calculated for two loading situations. Case I provided that the artesian pressure in both the Alta Loma Sand of Rose (1943) and Evangeline aquifer would continue to decline at a rate of 6 feet per year until 1980 and then cease. Case II provided that artesian pressure in the Alta Loma Sand would continue to decline at a rate of about 6 feet per year until about 1995, when the potentiometric head would reach the top of the Alta Loma Sand. The artesian pressure in the Evangeline aquifer would also decline about 6 feet per year until 1995. The ultimate subsidence expected for the assumed conditions of case I and case II is 11.2 feet and 14.5 feet, respectively. However, only 1.8 feet of subsidence below present land surface would occur if artesian pressures were maintained at their present levels. To halt subsidence in the near future, artesian pressure must be increased. The most logical method of increasing artesian pressure is by decreasing pumpage rather than repressurization by artificial recharge.

Texas↗
USGS1974

Effects of septic tank effluent on ground-water quality, Dade County, Florida: an interim report

At each of five sites in Dade County, where individual (residence) septic tanks have been in operation for at least 15 years and where septic tank concentration is less than 5 per acre, a drainfield site was selected for investigation to determine the effects of septic tank effluent on the quality of the water in the Biscayne Aquifer. At each site two sets of multiple depth wells were drilled. The upgradient wells adjacent to the drainfields in most places, were constructed in such a way that the aquifer could be sampled at 10, 20, 30, 40, and 60 feet below land surface. The down-gradient wells at each site are 35 feet or more from the up-gradient wells in the direction of ground-water flow, and allow. the aquifer to be sampled at various depths. Except at one site, no fecal coliforms were found below the 10-foot depth. Total coliforms exceeded a count of one colony per ml at the 60- foot depth at two sites. At one site a fecal streptococci count of 53 colonies per ml was found at the 60-foot depth and at another a count of seven colonies was found at the 40-foot depth. The three types of bacteria occur in higher concentration in the northern areas of the county than in the south. Bacteria concentrations were also higher where the septic tanks were more concentrated.

Florida↗
USGS1974

Progress report on flood magnitude and frequency of Vermont streams

A technique is presented for estimating the magnitude and frequency of floods on streams in Vermont with drainage areas between 0.27 and 1,040 square miles. Multiple-regression techniques are used to define the relation between flood peaks, collected at a network of gaging stations maintained by the U.S. Geological Survey, and a set of basin characteristics. Results show that flood peaks may be estimated from knowledge of the basin's drainage area, average seasonal snowfall, area of lakes and ponds, and maximum 24-hour rainfall having a recurrence interval of 2 years. The relations are presented graphically for user convenience.

Vermont↗