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	La Negrillar
Synonyms: None
Location: 24º17'S; 68º36'W
Country: Chile
Summit Elevation: 3650m
Edifice Height: 100m
Type: Discrete Maar

Other mafic monogenetic features include discrete centers such as the maars of Cerro Overo, Cerro Tucle and large compound flows as at La Negrillar. Cerro Overo (23° 31'S 68° 19'W) is a young 600 m diameter maar erupted along a regional fault through a basement of ignimbrites. It is least silicic young volcanic rock so far found in the 21° to 24°S segment of the volcanic Central Andes (54.22% SiO2). Cerro Tucle is somewhat older but is also related to regional faulting. The siting of La Negrillar (24° 17'S 68° 36'W) has been controlled by by faults on the southwestern flank of the Atacama basin. This compound basaltic andesite cone and lava complex is valley confined but of considerable extent with a maximum dimension of about 16 km.