Magnetic comparison of explosion craters and volcanic cones

Abstract

The magnetic responses of various volcanic structures show that cinder cones systematically present the strongest magnetic responses, while explosion craters with ash rings appear to be weakly magnetized. Structures that arc or the collapse type, which may or not be associated with an explosive origin, do not show systematic magnetic behavior. These results suggest that ash rings appear when the initial explosion is shallow, while deep explosions tend to produce surface features of the collapse type. The inference is made that the intrusive rhyolites known as Las Derrumbadas in the Oriental-Serdan Basin may be a geothermal source.