Monogenic volcanoes of Patagonian back-arc province,southern Argentina

A MOTOKI; Y ORIHASHI; D HIRATA; MJ HALLER; T HOSONO; CARIO DIAS, F; M SCHILLING; R ANMA

Journal Of The Geological Society Of Japan

Lugar: Japon; Año: 2003 vol. 109 p. 1 - 1

In the southern Andes back-arc, behind the South Volcanic Zone (SVZ) and Austral Volcanic Zone (AVZ), hundreds of monogenic basaltic volcanoes took place, forming numerous cinder cones and lava flows. The eruption age ranges from the Oligocene to the Recent. The lava flows cover the top of sedimentary plateaus, as cap rock, forming table mountains, so-called “mesetas”. In many cases, the plateau top lava is composed of only one cooling unit, less than 10m think. Accumulated lava flows also are observed, and they are generally made up of less than four flow units, as much as of 30m total thick. Some young lava flows, which fill glacial valleys, show lava cascades. Certain lavas and scoria falls are very fresh.