A LOWER CRETACEOUS VOLCANO IN MAKHTESH RAMON (SOUTHERN ISRAEL)

摘要

In the north-eastern area of Makhtesh Ramon, which lies in the southern part of Israel, a basalt hill is exposed with a summit 70m above its surroundings and an area of 1 sq. km. This hill is composed of mainly olivine basalt and partly of tuff. It is approximately hoof-shaped, with a low centre and a drainage outlet towards the south. It is postulated that this structure is the result of a volcanic eruption which started with an explosion of tuff, followed by the eruption of basaltic lava streams. During the last stage of this eruption the interior pressure was released and the part above the feeding neck sank. The volcano erupted in Early Cretaceous and was covered by sandstones of the Lower Cretaceous Kurnub formation, which preserved it until it was uncovered by recent erosion.