Geophysical database of the east coast of the United States; southern Atlantic margin, stratigraphy and velocity in map grids

Abstract

In 1990, the Naval Oceanographic Office and the U.S. Geological Survey agreed to develop a digital data base of stratigraphy and acoustic properties of sediments along the U.S. East Coast of the United States. The objective of this work was to utilize more than 25,000 km of publicly available multichannel seismic-reflection profiles (Sheridan et al., 1988) in order to assign acoustic properties to the continental margin postrift sediments in an internally consistent, geologically meaningful, regionally extensive, digital form. The acoustic properties of interest include thickness, depth, compressional- and shear-wave velocity, compressional- and shear-wave attenuation, density, and lithology. This data base subdivides the 0- to 14-km thick Jurassic and younger postrift deposits into 18 mappable horizons. The spatial scale of gridding is 5' latitude by 5 ' longitude, or about 9x8 km. This report describes the second part of developing the data base for the continental margin between Florida and Cape Hatteras: spatial gridding of the digital stratigraphic and velocity data, derivative calculations of density, shear-wave velocity, and attenuation, and construction of the final data base. The first report (Hutchinson et al., 1995) describes how the stratigraphy and velocity were digitized from the original profiles. Complementary reports that describe the data base for the area between Cape Hatteras and Georges Bank are given in Klitgord and Schneider (1994) and Klitgord et al. (1994).