Gravity Field of the Northwest Pacific Ocean Basin and its Margin: Aleutian Island Arc-Trench System.

摘要

Surface-ship and pendulum sea gravity measurements have been combined with land measurements in a new free-air anomaly map of the Aleutian island arc-trench system. The most prominent features of the map are a narrow belt of large-amplitude positive anomalies that reach a maximum value of +242 mgal over the northwest part of the Aleutian island arc and a narrow belt of large-amplitude negative anomalies that reach a minimum value of -219 mgal over the central part of the Aleutian Trench. The map also defines the main features of the free-air anomaly field landward of the Aleutian arc and seaward of the Aleutian Trench. Free-air anomalies are generally zero over the Aleutian Basin landward of the central part of the Aleutian island arc and generally positive (as much as +50 mgal) seaward of the Aleutian Trench. (Author)