Accession Number : ADA956087

Title :   The Gravity Field and Plate Boundaries in Venezuela.

Descriptive Note : Doctoral thesis,

Corporate Author : WOODS HOLE OCEANOGRAPHIC INSTITUTION MA

Personal Author(s) : Folinsbee, Robert A.

Report Date : JAN 1972

Pagination or Media Count : 161

Abstract : Free-air and simple Bouger anomaly maps of the Venezuelan continental margin are presented. The major features of the free-air map are: the large lows associated with the deep sedimentary basins, -200 mgal in the eastern Venezuela basin and -164 mgal in the Maracaibo basin; the high of >300 mgal over the Venezuelan Andes; and a belt of highs associated with the offshore islands. The Bouger anomaly map shows a large flow over the Eastern Venezuelan basin and relative minimums over the coastal mountains. A minimum associated with the Venezuelan Andes is shifted to the northwest of the topographic axis and lies over the flank of the Andes and part of the Maracaibo basin. Using the gravity data, structural sections were constructed for a series of profiles across the Venezuelan Andes and Caribbean mountains. They show there is no light crustal root under the Andes, the relative mass excess is as much as 600 kg/sq cm, and there is an excess of low density material under the Maracaibo basin.

Descriptors :   *BOUGUER GRAVITY ANOMALIES, VENEZUELA, THESES, GRAVITATIONAL FIELDS, BOUNDARIES, PLATE TECTONICS, EARTH CRUST, MOUNTAINS, GEODETIC SURVEYS.

Subject Categories : Geodesy

Distribution Statement : APPROVED FOR PUBLIC RELEASE