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Geology topics

R.D. Watts

Publications and source records attributed to R.D. Watts.

6 recordsLinked to original sources
USGS2017

Systems for measuring thickness of temperate and polar ice from the ground or from the air.

Equipment has been designed and tested for ground-based and airborne sounding of temperate glaciers. The transmitter is a free-running pulse generator that uses avalanche-mode transistor breakdown to create high-voltage pulses. The transmit and receive antennas are resistively loaded dipoles; for the airborne system, a twin-lead transmit element and a three-layer coaxial receive element are used on the inboard end of the respective antennas. The sounders are broadband systems; oscilloscopes are used for receivers. The oscilloscope trace is recorded photographically in the ground-based systems. A sampling oscilloscope is used in the airborne system—the sampling process strobes the waveform to audio frequencies so that it can be recorded on magnetic tape. Echoes have been obtained from ice depths of 550 m using the airborne system and about 1 000 m using the ground-based system.

Journal of Glaciology↗
USGS2007

Roadless space of the conterminous United States

Roads encroaching into undeveloped areas generally degrade ecological and watershed conditions and simultaneously provide access to natural resources, land parcels for development, and recreation. A metric of roadless space is needed for monitoring the balance between these ecological costs and societal benefits. We introduce a metric, roadless volume (RV), which is derived from the calculated distance to the nearest road. RV is useful and integrable over scales ranging from local to national. The 2.1 million cubic kilometers of RV in the conterminous United States are distributed with extreme inhomogeneity among its counties.

Science↗
USGS1982

Interpretation of Schlumberger DC resistivity data from Gibson Dome-Lockhart Basin study area, San Juan County, Utah

A Schlumberger dc resistivity survey of the Gibson Dome-Lockhart Basin area, San Juan County, Utah, has revealed the following electrical characteristics of the area: (1) the area between the northern part of Davis Canyon and Gibson Dome is electrically quite uniform and resistive at the depth of the Pennsylvanian evaporite deposits, (2) there is a deep conductive anomaly at Horsehead Rock, and (3) there are several shallow and deep electrical anomalies in the vicinity of the Lockhart fault system. No adverse indicators were found for nuclear waste repository siting south of Indian Creek, but additional soundings should be made to increase data density and to extend the survey area southward. The Lockhart fault system appears to have triggered salt dissolution or flow outside the limits of Lockhart Basin; further geophysical work and drilling will be required to understand the origin of the Lockhart Basin structure and its present state of activity. This problem is important because geologic processes that lead to enlargement of the Lockhart Basin structure or to development of similar structures would threaten the integrity of a repository in the Gibson Dome area.

Open-File Report↗