Final Report on Gravity Program

Abstract

The report presented is the final one under Air Force Cambridge Research Center Contract 19(604)·2157 with the Woods Role Oceanographic Institution. The report covers a program of pendulum and gravimeter measurements conducted over the period 1950·1959. The original objective of the program was to establish a series of reliable gravity control measurements through the use of pendulums over a sufficient range of gravity to permit the calibration of geodetic gravimeters with an accuracy of one part in 5000 over a range of 5000 mgals and thus assure a potential accuracy of 1 mgal or better with such gravimeters on any global series of measurements. With time this objective was modified to include the establishment of pendulum gravity measurements outside of North America as there appeared to be no unanimity of international opinion regarding a gravity standard. A second objective of the program was to expand the gravity coverage and standardize existing gravity surveys within the United States so that reliable gravity anomaly maps could be prepared. A third objective was to strengthen and expand the world network of airport gravity bases established earlier under the auspices of the Office of Naval Research so that data in all parts of the world could be integrated onto the same datum and gravity standard. The report is subdivided on the basis of these objectives into three principal parts plus an introductory chapter giving the history o~ the program, and a final chapter presenting recommendations as to further work deemed desirable. Dr. J. C. Rose, who has been in charge of the pendulum program since its inception, prepared the second portion of the report, which deals with the pendulum measurements, and the writer prepared the remainder.