Neotectonism In Solon-Ulanhot Area

The study area is located in the Central of Da Hinggan Mts， affected by DaHiggan Mts uplift of active neotectonic movement, mainly the performance of terraceuplift movement, volcanic activity, earthquakes etc., and in different parts of the sameperiod or the same area of different periods, there are different forms.Through a field geological survey and profile measurements, from northwest tosoutheast to the series of river terraces and type in different stages of the obviousdifferences in the study area.Neogene has been the study area twice suffered the roleof peneplanation development of the Xing’an peneplane and Boosy planation surface.Subsequently crust in constant uplift, steadility, and the resulting development of amulti-level terraces. Along the Tao’er River upstream development IV,Ⅴ-levelterraces and Boosy planation surface, the middle reaches of the development ofⅡ,III-level terraces; the downstream of Ulan River,and Tao’er River, the two sidesof Guiliu rive and Ulanhot southeast, only the development of the floodplain andⅠlevelterrace,Ⅰ terraces in some places damaged by the modern river bed.Field geological mapping found, the volcanic activity is mainly Wuchagou basaltand Xikou basalt eruption. Basalt from Tao’er River upstream to downstream, alongthe coast of Guiliu River and affluent. the thickness of basalt eruption graduallyincreased, the lithology is also evolution from basalt to alkaline basalt, is followedinto the neutral basalt, from the river bed surface height decreased gradually reduce,eruption cycle times are decreasing.Cenozoic faults is mainly the pre-fracture revived along with some of thenewborn fracture in the study area. Mainly as Ulan River north of the North East,North West fracture to the two groups were revived, and the Solun northwest NewCathaysian tectonic system in the wuchagou-30kilometers fracture.Cenozoic deposits in the distribution of the thickness of the causes of thelithology and lithofacies characteristics, combined with isotopic ages, and topography,the characteristics of volcanic activity and earthquakes, new tectonic movement canbe divided into the Miocene-Pliocene and Early Pleistocene the world, in thePleistocene-Late Pleistocene and Holocene in four phases. While the new type oftectonic movement, intensity and duration may be different, but by the level of stressand vertical stress relationship point of view, the mechanism should be the same. Thestudy area is located between the North and Siberia, the convergence of two plates with, and long-term control of these two plates, and strong in the late Variscan andYanshanian orogeny tectonic movement. Neotectonic movement by the West Pacificplate subduction and collision of the Eurasia plate, the mantle magma and theasthenosphere disturbance, magma upwelling due to stretching exercises alternately,so that the regional stress field changed many times, the occurrence of crustal uplift,volcanic activity.