GEOLOGY 103 Lecture Notes - Lecture 14: Basalt
Document Summary
Volcanism and resurfacing on venus: the surfaces where genera probes anded consists of basalt rubble, some lava surface are radar-bright (rough) and my correspond to a"a or block lavas, some are radar-dark and may be pahoehoe lavas. Volcanoes are a eld of small shields or low domes. Sif mons are a shield with young lava. Sacajawea is a venusian caldera: a venusian tick volcano is unlike anything on earth. Coronae and arachnoids are also unique to venus: coronae are much larger than calderas, and may be caused by mantle plumes on venus. Mantel plumes cause volcanism on venus, earth and mars: coronae tend to be associated with fault zones. Tectonic: in addition to zones of extension, venus has areas of compression. Areas of complex tectonic history are mostly located in the highlands and are the oldest surfaces on venus. History of venus: predominately a volcanic planet, but little or no magma inside venus at present, early history unknown.
