Taapaca is located on the western margin of the Altiplano, where the Western Cordillera has developed since the Oligocene. The basement beneath the volcano is formed by several principally volcanic formations, including the Lupica and sedimentary Huaylas formations and the Lauca ignimbrite (2.72 million years old); this basement is of Oligocene to Pliocene age. In some places, a Proterozoic basement formed by amphibolites, gneisses and serpentinites crops out. The volcanoes of Condoriri, Pomerape, Larancagua and Parinacota lie to the east of Taapaca. The area of the volcano is subject to contractional tectonics, with a major thrust fault passing close by, but their relationship to Taapaca's volcanism is not clear.