Study On Quaternary Volcanic Activity And The New Tectonics,Chaoer River,Zhalantun City,Inner Mogolia

The study area is located in the southwest of Inner Mongolia Autonomous Region eastern Zhalantun City Chaihe area,belong to the the Daxinganling northern section of the southern main peak of the southeastern slope.Pre-Mesozoic regional tectonic unit are Paleo-Asian tectonic domain.Cenozoic regional tectonic units are Western Pacific tectonic domain.Cenozoic volcanic activity is mainly affected by the inherited fault controlled.Chaoer river is one of the major river systems in the region.There are large areas of the late Pleistocene valley basalt in the upper and middle of the Chaoer Valley,belong to the Upper Pleistocene large black trench group(Qp3d).The lithology lherzolite xenoliths containing alkaline olivine basalt.Landscape composed of two terraces,was north-northwest trending along the Chaoer Valley.North-south length of about 110km.Width is generally 1-5km at its widest point in Chaihe Town,up to 10km.The distribution area is 224km2 and the thickness is about 25-30m.The volume is approximately 4480-5600km3.The traditional view that basalt is a volcanic overflow Chaoer Heyuan flows of lava along the valley.This article is a volcanic study,focuses on the distribution characteristics of the space of the valley basalt,the thickness change,the flow of lava flows,columnar jointed,diabase dike and near the crater.Splashdown accumulation characteristics.Therefore,we argue that the Chaoer Valley basalt is fissure eruption product,belong to a fractured volcanic edifice.It provides important information to explore the the Daxinganling Quaternary deep magma activities and the new structural characteristics.In late Pleistocene,Chaoer Valley volcano eruption is phreatomagmatic eruption,which formed base surge.The similar to Iceland-type volcano overflow quietly along the Chaoer river fracture.It accumulated a large amount of alkali basalts that containing herzolite xenoliths.The tectonic movement of the study area mainly for the differences in fault block uplift、the formation of new fracture、the inheritance of basement faults and volcanic eruptions.Chaoer river is a NNW trending fracture that tracks the NE and NW trending fracture.The fracture of different directions since the Quaternary as the nature of the normal faults,reflecting the deep magma underplating may be the main reason to control the activities of the newly constructed.