Gravity surveys were made in December 1960 over areas of ferruginous and siliceous laterite in the Mount Davies region, where a sill-like body of basic and ultrabasic igneous rocks, the Giles Complex, intrudes Archaean metasediments. Secondary nickel mineralisation is associated with the laterites. The surveys have indicated that gravity methods can successfully delineate the ferruginous laterite bodies, with good results obtained in determining the extent of one such body at Claude Hills; however, gravity methods do not appear capable of tracing the siliceous laterites, except under exceptional circumstances.