Study on the geology of Gezi Shan volcano in Xilinhot,Inner Mongolia

Gezi Shan volcano is located in the southeastern Xilinhot of XilinGol League in Inner Mongolia Autonomous Region and tectonically belongs to the central part of Daxing'anling-Datong volcanic belt,It is the most intact basaltic volcano in the Xilinhot-Abaga volcanic cluster,The distribution area of the volcanic products is about 55km2,The main products of Gezi Shan volcano are landed scoria,splashdown welded pyroclastic rock and lava flows,They are main basanites,with minor late-stage olivine tholeiites,The basanites contain abundant lherzolite xenoliths,pyroxene and anorthoclase megacrysts,Gezi Shan volcano comprises volcano cone,lava flows and volcano clastic seats,The volcano cone is the composite of early landed cone and later splashdown cone,The crater was changed into a typically broken crater due to multiple collapses,Two lava overflow ports,which still keep their original forms,are observed in the west and the northeast sides of the cone,The type of the lava flows is encrustant lava,composed of several lava flow units,There are lots of well-kept fumarolic cones of different kinds in some parts of the lava flows,Clastic seats in the volcano are mainly distributed in the east side of the cone,The further from the volcano cone,the thinner the volcano clastic seats are,The volcanic activity of Gezi Shan can be divided into two stages,The volcanic activity during early stage was explosive eruption and produced the landed scoria cones and the clastic seats,The eruption belongs to week-brinley type,Late-stage volcanic activity was overflow eruption and produced the splashdown cones and massive lava flows,The eruption era of the Gezi Shan volcano is the end of Late Pleistocene to Holocene.