El Negrillar is a volcanic field in the Andes. Located west of the Cordón de Púlar, it generated cinder cones and andesitic lava flows. The volcanic field may be of Holocene age. Parts of the Socompa debris avalanche overlie the field. The cones have volumes of less than and lava flows are thin and branch out dendritically. Lava flows are up to thick and overlie the Salín Formation. The origin of the more basic lavas of this field has been explained with olivine differentiation.