Sima Pumacocha
Sima Pumacocha (possibly from Spanish sima deep and dark cavern/abyss,Quechua puma cougar, puma, qucha lake) is a limestone cave located in the Lima Region, Yauyos Province, Laraos District, in central Peru near the village of Laraos, high in the Andes mountains. It is one of the deepest caves in South America. It is located at 12°23′29″S 75°42′00″W / 12.3914°S 75.7°W.
At 4,300 m to 4,400 m above sea level, the Pumaqucha valley is a typical Andes 'puna' – high, treeless, and surrounded by 5,000 m peaks. The valley is traversed by a dirt road serving active and abandoned mines nearby, and is dotted with stone huts used by locals tending flocks of sheep, llamas and alpacas. At the head of the valley is Pumaqucha, a small lake which along with its catchment area sits atop Miocene age granodiorite. Where the lake's outfall stream meets near-vertically bedded Cretaceous age Jumasha limestones, it has carved a short, shallow canyon containing several abandoned and one active sinkpoint where the entire stream disappears underground. Underlying the limestone is the Lower Cretaceous Pariatambo Formation.
A small concrete canal, intended to keep the lake outfall on the surface by diverting it around the canyon, is in poor shape and normally does not function at all. When local repairs occur, the active sinkpoint (SP1) becomes enterable, but considerable water then leaks into the abandoned sinks (SP2 and SP3).
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