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D. R. Hutchinson

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

46 records · Page 3Linked to original sources
USGS1986

Free-air gravity anomaly map of the Long Island Platform

The U.S. Geological Survey (USGS) has collected marine gravity data along the U.S. Atlantic continental margin during the last decade. This map of the Long Island platform combines the data used to make the preliminary free-air gravity anomaly map of the Atlantic continental margin (Grow and others, 1976) with the new gravity values collected aboard the RV Gilliss in 1979 and the RV Gyre in 1981. Carl Bowin provided the USNS Kealthley data from the Woods Hole Oceanographic Institution gravity data-base. We thank Bab Bowles (USGS) for his advice on editing the navigation and gravity data.

Long Island↗
USGS1984

Water gun vs air gun: A comparison

The water gun is a relatively new marine seismic sound source that produces an acoustic signal by an implosive rather than explosive mechanism. A comparison of the source characteristics of two different-sized water guns with those of conventional air guns shows the the water gun signature is cleaner and much shorter than that of a comparable-sized air gun: about 60-100 milliseconds (ms) for an 80-in3. (1.31-liter (I)) water gun compared with several hundred ms for an 80-in3. (1.31-1) air gun. The source spectra of water guns are richer in high frequencies (>200 Hz) than are those of air guns, but they also have less energy than those of air guns at low frequencies. A comparison between water gun and air gun reflection profiles in both shallow (Long Island Sound)-and deep (western Bermuda Rise)-water settings suggests that the water gun offers a good compromise between very high resolution, limited penetration systems (e.g. 3.5-kHz profilers and sparkers) and the large volume air guns and tuned air gun arrays generally used where significant penetration is required. ?? 1984 D. Reidel Publishing Company.

Marine Geophysical Research↗
USGS1982

Deep structure and evolution of the Carolina Trough

Multichannel seismic-reflection data together with two-dimensional gravity and magnetic models suggest that the crustal structure off North Carolina consists of normal continental crust landward of the Brunswick magnetic anomaly (BMA), rift-stage crust in the 80-km-wide zone between the BMA and the East Coast magnetic anomaly (ECMA), and normal oceanic crust seaward of the ECMA.

Book chapter↗