The dominating feature of the regional Bouguer anomaly contours is a continuous gravity ridge trending east-south-east across MANN and possibly extending across WOODROFFE. This ridge seems to be a continuation of the Anketell gravity ridge which persists northwest across Western Australia to the Indian Ocean. Local gravity highs on this ridge coincide with outcropping Giles Complex rocks and seem to indicate that the outcropping areas of basic rock are the surface expression of apophyses emanating from a larger body at depth. This larger body is probably continuous across the area investigated and possibly extends in depth to at least several tens of thousands of feet. The author believes that this gravity ridge of 70 to 100 mGal in magnitude is caused partly by some major crustal feature and partly by the Giles Complex intrusion. The shape of the gravity anomalies obtained seems to suggest that the basic intrusion is structurally controlled along the northern margin. An aeromagnetic survey over this area has been analysed qualitatively.