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John Stevens Schlee

Publications and source records attributed to John Stevens Schlee.

At least 19 recordsLinked to original sources
USGS1980

Mid-Atlantic multichannel seismic-reflection profiles 14, 15, 16, and 17

The U. S. Geological Survey (USGS) is making available four multi­channel profiles collected by Teledyne Exploration in 1977 by means of a 48-channel streamer (3600 m long) and four airguns (2160 in). Profiles 15 and 16 were processed by.Teledyne Exploration and profiles 14 and 17 were processed on the Phoenix "I"* computer·by the USGS. The processing included standard demultiplexing, deconvolution before and aftfer stack, Common Depth Point (CDP) gathers, velocity analyses every 3 km, move-out correction, stacking, time-variant, filtering, and time-variant scaling. The released lines are over the outer edge of the Continental Shelf in the northern part of the Baltimore Canyon trough (Line 14: 140 km long and Line 15: 157 km long), over the Long Island platform. (Line 16: 313 km long), and over the Carolina platform (Line 17: 186 km long). These profiles were collected as a part of a regional grid over offshore Atlantic sedimentary basins in a continuing program to assess the resource potential by means of nonproprietary data. These profiles, plus the velocity scans and shotpoint maps, may be viewed at U. S. Geological Survey, Quissett Campus, Woods Hole, MA. 02543, and U. S. Geological Survey, Bldg. 25, Denver Federal Center, Denver, CO. Copies of maps, scans, and profiles can be purchased only from the National Geophysical Solar-Terrestrial Data Center, Environmental Data Service (NOM), Code D 621, Boulder, CO 80302.

Open-File Report↗
USGS1980

Multichannel seismic-reflection profiles collected along the U.S. continental margin in 1978

During 1978, the U.S.. Geological Survey (USGS) contracted with Geophysical Services, Inc. (GSI) for GSI to collect 4,813 km of 48-channel seismic-reflection profiles along the continental margin between North Carolina and Maine. Fifteen lines were acquired perpendicular to the margin Clines 18 through 32), and six lines were acquired parallel to the margin Clines 33 through 38). The profiles were shot by the Motor Vessel (MV) CARINO and MV CECIL GREEN between May and November 1978. A 3,600-long hydrophone streamer was used; it was composed of 24 groups of 100-m length each near the ship, followed by 24 groups of 50-mlength each. Tuned airgun arrays totaling 2,000 and 1,400 cubic inches of air were used by the MV- CARINO and MV CECIL GREEN, respectively. The profiles were stacked by GSI and displayed in conventional time-variant scaled format to 12 seconds of recording time with vertical scales of .2.5 inches per second and horizontal scales of 1.2 km per inch. Additional protessing was applied to Line 25 across the Baltimore Canyon Trough and Line 32 across the Carolina Trough. Data collected along Line 25 over the Outer Shelf, Slope and upper Rise were restacked with 1 1/2-km-spaced velocity analyses, signature deconvolution, deep-water multiple deconvolution, velocity filtering Con shelf only), and time migration. The restacked part and remaining parts of Line 25 were converted to depth sections having a vertical scale of 1.2 km per inch (vertical exaggeration: 2/1). Data collected along two parts of Line 32 were also restacked with signature and deep-water multiple deconvolution. Line 32 was also converted to a depth section except for the first 80 km near shore. Profiles 18-38 may be inspected at the USGS in Woods Hole, MA 02543. Copies of the profiles may be, purchased only from the National Geophysical and Solar-Terrestrial Data Center, NOAA, Boulder, Co 80303.

Open-File Report↗
USGS1979

Summary report of the sediments, structural framework, petroleum potential, and environmental conditions of the United States Mid-Atlantic continental margin in area of proposed Oil & Gas Lease Sale No. 59

This report has been compiled to update and summarize the geological information concerning the area of the Atlantic continental margin off the U.S. Mid-Atlantic proposed for Oil and Gas Lease Sale No. 59 (fig. 1). The region of interest lies between 35° and 41° N and 70.5° and 76° W. The north-south dimension is about 660 km (356 nautical miles, 410 statute miles) and the maximum east-west dimension is approximately 250 km (135 nautical miles, 155 statute miles). The area is centered toward the outer Continental Shelf off Delaware and contains more than 154,000 km2 (38,000,000 acres) off the coasts of North Carolina, Virginia, Maryland, Delaware, New Jersey and New York. Water depths within the region range from 20 to slightly more than 4,000 m (fig. 1). This report begins with a discussion of the regional geology and geophysics, followed by a description of the oil and gas potential and potential environmental hazards.

Delaware, Maryland, New Jersey, New York, North Ca↗
USGS1978

Bottom currents and bottom sediment distribution in Massachusetts Bay

Massachusetts Bay is a coastal Bay 100 km long and 40 km wide located in the western Gulf of Maine. The Bay is open only to the Gulf to the east; the opening is partially blocked by a shallow bank. The bottom sediment distribution in the bay is complex; fine grained material is found in the deep basin, sand and gravel on the shallow bank, and mixtures of sand, gravel and finer sediments nearshore. Richardson current meters were moored l m from the bottom over a one-year period at several locations in the Bay to define the bottom currents and to determine the frequency of bottom sediment movement due to currents. The measurements suggest that the bottom sediments can be expected to move occasionally in certain areas. The maximum bottom current speeds were determined principally by the strong tidal currents in the basin. In winter, the near bottom currents were dominated by wind stress associated with storms. Bottom currents in the shallow areas were generally in the direction of the wind while currents in the deep portion of the basin were often opposite to the direction of the wind. Sea-surface setup in the direction of the wind was observed, as well as variations in sea level attributed to changes in the adjacent Gulf of Maine. Adjustment of the bottom current to windstress required approximately 12 hours. Total concentrations of suspended particulate matter, in general, were found to be higher in the near-shore and near-bottom waters and lower in the offshore and near-surface waters. Near-bottom concentrations tended to increase as the grain size of the bottom sediments decreases. The greatest concentrations of suspended matter were observed in waters adjacent to Boston Harbor.

Open-File Report↗
USGS1978

Notes on the availability of mid-Atlantic multichannel seismic reflection profiles 11 and 12-A, -B, -C, and -D

Available are two multichannel profiles collected by Digicon Geophysical Corporation in 1975 using a 48-channel streamer (3600 m long). and a 27.9 cu. liter air gun array. They were processed in Denver on the Phoenix "I" by William C. Patterson. The processing included demultiplexing and resampling, geometry and common-depth-point definition, velocity analysis, noise muting, band-pass filtering, time-variant filtering, time-variant deconvolution, and automatic gain control (AGC) scaling, prior to the final profile playout. The release includes parts of two lines off the mid-atlantic continental margin (see map) over the Baltimore Canyon trough. These profiles were collected as part of a regional grid over the offshore Atlantic sedimentary basins, as a part of a continuing program to assess the resource potential using non-proprietary data Line 11 is a cross shelf profile (233 ken long) taken across the shelf, slope and upper rise off Virginia (southern Baltimore Canyon trough). Line 12 (shotpoint 1Ol- 6011, parts A, 8, C and D) is an along-the-shelf profiler and stretches from the Cape Hatteras IPOD line to line 2, at the northern part of the Baltimore Canyon trough), a distance of 591 km. These profiles may be viewed at the U.S. Geological Survey, Atlantic Gulf of Mexico, Office of Marine Geology, Quissett campus, Building B, Woods Hole, Massachusetts 02543, and at the U.S. Geological Survey, Branch of Oil and Gas Resources, Denver Federal Center, Building 25, Denver. Colorado 80225. Copies of the profiles can be purchased from the Nations Geophysical and Solar-Terrestrial Data Center, Environmental Data Service- NOAA, Code D621 Boulder, Colorado 80303.

Open-File Report↗
USGS1975

Structure of continental margin off Mid-Atlantic states (Baltimore Canyon Trough)

Increasing interest in the Atlantic continental margin as a future petroleum province has resulted in several recent papers (Emmerich, 1974; Burk and Drake, 1974) that attempt to summarize the structure and stratigraphic framework of this area. Most papers tend to portray the margin as a wedge of Mesozoic and Cenozoic sediment that thins at the edge of the shelf over a "basement ridge" and then thickens again under the continental rise. Off the northeastern United States, the sediment wedge under the shelf attains a thickness of 8-11 km in the Georges Bank basin (Schultz and Glover, 1974; Mattick and others, 1974; Sheridan, 1974b; Behrendt and others, 1974) and 12 km in thickness in the Baltimore Canyon trough off the middle Atlantic states of Delaware, Maryland, Virginia and New Jersey (fig. 1). Seaward of the continental shelf and its sediment prism, Emery and Uchupi (1972, figs. 133-135) infer slump deposits (eroded in some areas) covering a buried ridge thought to extend from the Laurentian Channel to Cape Hatteras, where it splits in two. The lower slope and continental rise are inferred by Drake and later investigators to be a thick prism of deep sea sediment (turbidites, hemipelagic clays, slump deposits) overlying oceanic basement in a welt that parallels the continental edge and reaches a maximum thickness of 6 km (Emery and Uchupi, 1972, fig. 188). Our purpose is to present the results of a geophysical survey across the margin seaward of the middle Atlantic states that comments on the structural - stratigraphic framework of the margin.

Open-File Report↗