GEOPHYSICAL AND GEOLOGICAL INVESTIGATIONS IN THE GULF OF MEXICO, PART I

In 1953 the research vessels vema and atlantis spent about three weeks in the Gulf of Mexico. Coring, seismic refraction, and topographic studies were undertaken. The topography in the various physiographic provinces is illustrated by reproductions of precision depth records from the continental shelf, continental slope, continental rise, and abyssal plain areas. Many sediment cores longer than 30 ft were taken in the Gulf. An abrupt change separates approximately three feet of Recent sediments from Wisconsin in all cores taken in depths greater than 1700 fathoms. This change is very similar to one found in many Atlantic and Caribbean cores indicating an abrupt termination of the Wisconsin glacial epoch. Abundant evidence of turbidity current deposition was found in all cores from the abyssal plain and the continental rise. Deposition of sediments in the unusually rough and broad continental slope area is apparently very rapid in the depressions and very slow on the elevations. The seismic results point to the southern half of the Gulf of Mexico as a typical oceanic area, modified by an increased load of sediments. A profound change near the continental slope is required for connecting this structure to typical continental structures.