Usgaon Ultramafic-Gabbro Complex, Goa

An intrusive complex comprising serpentinized dunite and peridotite, metagabbro and troctolite occurs near Usgaon in the central part of Goa. Ultramafic members are chromiferous and host a lenticular body of chromite. The complex occurs as an U-shaped body around the hinge of a NW-SE trending regional synform. Structural and textural studies suggest that the complex was emplaced prior to folding (F₁) and participated in the deformation and metamorphism together with the schistose host rocks. The post-tectonic period witnessed two major periods of dyke activity essentially of gabbroic and doleritic composition respectively.