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G. W. Hill

Publications and source records attributed to G. W. Hill.

13 recordsLinked to original sources
USGS1989

1989 Exclusive Economic Zone symposium: Summary and recommendations

The fourth in a series of biennial national Exclusive Economic Zone symposia was held on November 14–16, 1989 . The purpose of the meeting was to examine ongoing and planned mapping and research activities in the ocean waters of the United States. Approximately 220 individuals attended the meeting. Issues discussed related to digital seafloor mapping projects, cooperative federal‐state programs, and requirements for additional data and information. Symposium recommendations included the need for increased surveying in coastal waters, development of standards for digital data dissemination, increased coordination with coastal states and federal agencies, and additional geophysical measurement systems abroad all mapping ships.

Marine Geodesy↗
USGS1988

Developing of 10-year EEZ seafloor mapping and research program

Mapping and research on the seafloor adjacent to the United States has been a national effort involving elements of the Department of the Interior, the Department of Commerce, certain academic institutions, and private industry, the latter primarily for the exploration for oil and gas. These activities were accelerated by the USGS and NOAA in 1983, following the issuance of the EEZ (Exclusive Economic Zone) Proclamation by President Reagan. The intent of expanding the exploration already begun on the outer continental shelf (OCS) to the frontier of the EEZ is to determine the “characteristics”; and resource potential of this region. To coordinate this exploration , a Joint Office for Mapping and Research (JOMAR) has been established by the U.S. Geological Survey (in the Department of the Interior) and the National Oceanic and Atmospheric Administration (in the Department of Commerce). JOMAR's main purpose is to help direct and coordinate ongoing and planned seafloor related activities in the EEZ and prepare a 10 ‐ year plan for mapping and research . JOMAR recently hosted a national symposium to identify the major elements of this plan . A comprehensive mapping and research plan will provide the needed direction and guide this national challenge.

Marine Geodesy↗
USGS1987

Progress report on the ground-water, surface-water, and quality-of-water monitoring program, Black Mesa area, northeastern Arizona, 1987

The N aquifer is an important source of water in the 5,400 sq-mi Black Mesa area on the Navajo and Hopi Indian Reservations. The Black Mesa monitoring program is designed to monitor long-term effects on the groundwater resources of the mesa as a result of withdrawals from the aquifer by the strip-mining operation of Peabody Coal Company. Withdrawals from the N aquifer by the mine increased from 95 acre-ft in 1968 to more than 4,480 acre-ft in 1986. Water levels in the confined area of the aquifer declined as much as 90 ft from 1965 to 1987 in some municipal and observation wells within about a 15-mi radius of the mine well field. Part of the drawdown in municipal wells is due to local pumpage. Water levels have not declined in wells tapping the unconfined area of the aquifer. Chemical analyses indicate no significant changes in the quality of water from wells that tap the N aquifer or from springs that discharge from several stratigraphic units, including the N aquifer, since pumping began at the mine. (USGS)

Open-File Report↗
USGS1985

Progress report on Black Mesa monitoring program, 1984

The N aquifer is an important source of water in the 5,400 square-mile Black Mesa area on the Navajo and Hopi Indian Reservations. The project is designed to monitor long-term effects on the ground-water resources of the mesa as a result of withdrawals from the aquifer by a strip-mining operation. Withdrawals from the N aquifer by the mine have increased from 95 acre-ft in 1968 to more than 4,000 acre-ft in 1984. Water levels in the confined area of the aquifer have declined as much as 75 feet in some municipal and observation wells within about a 15-mile radius of the mine well field. Part of the drawdown in municipal wells is due to local pumpage. Water levels have not declined in wells tapping the unconfined area of the aquifer. Chemical analysis indicate no significant changes in the quality of water from wells that tap the N aquifer or from springs that discharge from several stratigraphic units, including the N aquifer, since pumping began at the mine. (USGS)

Open-File Report↗
USGS1980

Nearshore current pattern off south Texas: an interpretation from aerial photographs.

Current patterns in a 4-km-wide zone along the south Texas coast were interpreted from patterns of water turbidity visible in aerial photographs taken during a winter day of moderate northerly winds. Features of the turbidity pattern remained recognizable on photographs taken 25 min apart. Currents measured from the movements of these features were southward and nearly parallel to shore, increasing from about 17 cm/sec in an offshore zone to about 40 cm/sec at the line of breaking waves. - from Authors

Remote Sensing of Environment↗
USGS1979

A radiographic scanning technique for cores

A radiographic scanning technique (RST) can produce single continuous radiographs of cores or core sections up to 1.5 m long and up to 30 cm wide. Changing a portable industrial X-ray unit from the normal still-shot mode to a scanning mode requires simple, inexpensive, easily constructed, and highly durable equipment. Additional components include a conveyor system, antiscatter cylinder-diaphragm, adjustable sample platform, developing tanks, and a contact printer. Complete cores, half cores, sample slabs or peels may be scanned. Converting the X-ray unit from one mode to another is easy and can be accomplished without the use of special tools. RST provides the investigator with a convenient, continuous, high quality radiograph, saves time and money, and decreases the number of times cores have to be handled.

Marine Geology↗