Formal gravity interpretation over the 800-m Darai escarpment in New Guinea

Abstract

A gravity traverse over the 800-m escarpment at Darai in New Guinea is analyzed using the formal interpretation approach in which processing and interpretation are combined in a fully computerized procedure. The topographic anomaly is computed by modeling the air‐rock interface, and the density of the escarpment is deduced from Nettleton’s density profiles after making allowance for upward continuation. To aid in the analysis, synthetic density profiles are produced for escarpment models and for the real escarpment. The analysis shows that a fault is located near the base of the escarpment and the bulk density there is [Formula: see text]. There is no vertical continuation bump directly over the fault. The upthrown basement is at a depth of roughly 2500 m. The fault’s position near the base of the escarpment suggests a history of repetitive crustal movements.