| 概要 |
The Kirisima volcano is a composite volcano constructed with younger and older volcanoes, the former of which consists of Homate, Konide, Tholoide and Maar types and the latter Aspite type (shield vol...cano). The arrangement of cones and craters is roughly north-west and south-east. They are distributed along several lines, radiating from the Ikenaga-Momogasako area within the so called "Kakuto caldera". As to the chemical compositions of lavas and scoriae, the lateral change of SiO_2 and S. I. (solidification index) show that the magma source is located within the Kakuto caldera. The total FeO-S. I. and SiO_2-S. I. relations show that the lavas of stratovolcano including Konide, are lower in Po, than the scoriae forming Homate, while the lavas of shield volcano are higher than the latter. It seems to be important in discussion of the relation between Po_2 and PH_2O in magma. The geothermal area occupies the south-western part of the volcano, where the distinct springs and fumaroles row is north west and south-east, and the hot spring temperature is high at the north-west part. The epicenters of the Ebino earthquake (1968) were located within the "Kakuto caldera". The depth of the hypocentral area of the earthquakes originating from the Kirisima volcano increases northwestwards from the shallowest Sinmoe-dake-Ohati area to the deepest "Kakuto caldera" area. These facts give significant suggestion for the construction of the "Kakuto caldera" and Kirisima volcano.続きを見る
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Mendeley出力
