Bouger gravity in the Wiseman quadrangle is dominated by a steep north-dipping regional gradient. Within the regional gradient are several residual anomalies that correspond spatially to mapped geologic units. These residual anomalies have a persistent east-west trend, attesting to the continuity of the east-striking geology. The northern end of the gravity gradient is a broad gravity low of down to -100 Mgal and is believed to be due to a low-density root near the core of the Brooks Range. The southern termination of this gradient is a relative gravity maximum located near the "suture" of the Arctic Alaska terrane with the Angayuchum terrane. This relative high is typical of sutures found throughout the world where continental and oceanic plates once converged. In this c se, the anomalies appear to be due to the juxtaposition of denser, mafic oceanic rocks to the south (Angayuchum terrane) with less dense, metamorphic continental rocks of the Arctic Alaska terrane to the north. By accounting for the relative densities of the rock units through gravity modeling, it is evident that the low-density root extends south to underlie the schist belt and possibly the mafics of the Angayuchum terrane.

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