Gravity Measurements in Alaska

Abstract

Outlines development and present status of observation program carried out by the authors since 1950. Field procedure consisted of establishment of base stations and a calibration standard for all gravity meters used, and setting up subsidiary base stations. Observations were made at 5- to 10-mile intervals along the highways, the Alaska Railroad between Fairbanks and Seward, and on an 800-mile trip down the Lewes and Yukon Rivers from Whitehorse to Circle. Free Air and Bouguer anomalies were determined, the latter being computed for selected densities to obtain maximum geological value. "Reasonably accurate regional anomaly maps" are presented for Naval Petroleum Reserve No. 4 and for southeastern Alaska; a generalized geologic map of Alaska with Bouguer anomalies (density=2.67) superimposed, indicates a great gravity low near Cook Inlet, and positive anomalies over the Aleutians, on the Yukon-Kuskokwim delta, and near Nenana. Available basic geodetic data are indicated; need for additional observations is stressed.