Paleoseismic Study Of Mesozoic Sedimentary Basins Of Continental Facies In Southwestern Henan

This paper research intermont small basins in southwest of Henan. Based on a lot offield work，indoor analysis of rock chip，grain size and cathode luminescent，the mainMesozoic basin of lithologic features， characteristics of sedimentary structure，paleogeographic evolution and the nature of the basin are analyzed. Meanwhile， basedon the analysis of the features of ancient earthquake records， the ancient earthquakerecords in Mesozoic continental deposition of southwest of Henan are described andsorted.The earthquake records widely developed in ChunShuyao formation of Yima basin.The lithology is mainly yellow and gray sandstone， silty sandstone. Sedimentaryenvironment is shallow lake. The types of earthquake records include slump structure，soft sediments deformation and shattered rock； The earthquake records in Liushan basindeveloped in a light gray thick layer of thin sandstone and silty mudstones. Thesedimentary environment is fan delta front. The types of earthquake records include softsediments deformation， slmup structre and turbidite deposit； The earthquake records inHuangtuling formation of Mashiping basin developed in the gray thick layer ofconglomerate and dark gray， yellow thin mudstone in central layer. The sedimentaryenvironment is the near shore submarine fan. The types of earthquake records includesoft sediments deformation and slump structure； The earthquake records in Nanzhaoformation of Mashiping basin developed in bottom of dark grey thin layer mudstone andcentral yellowish gray thin layer shale clip siltstones. The sedimentary environment is fandelta. The types of earthquake records include slump structre， turbidite deposit and softsediments deformation； The earthquake records in Gaogou formation of Xixia basindeveloped in the top layer of yellow， gray including gravel sandstone， silty sandstoneand silty mudstones. The sedimentary environment is alluvial fan. The types ofearthquake records include the same sedimentary fracture and soft sediments deformationstructure， slump structre， reformed fluvial deposit； The earthquake records in Majiagou formation of Xixia basin developed in the bottom red， grey including gravelsiltstones. The sedimentary environment is alluvial fan. The types of earthquake recordsinclude syn-sedimentary fault and soft sediments deformation.Based on the sedimentation and sedimentary structure background analysis ofMesozoic small basin in north Qinling area of southwest Henan， the paper identifies theancient earthquake records in these continental stratums. According to the earthquakerecords and sediment material deformation， the earthquake records are divided into twocategories. The first class is earthquake sediment record， including the seismite，molasse， turbidity deposition and reform of the river sedimentation； the second class issoft sediments deformation， including slump structure， soft sediments deformation andfractures， each of class includes different earthquake structure. The ancient earthquakerecords in continental semimetal basin not only reveal strong tectonization role in thesedimental process， but also provide information for the study of ancient geography andancient tectonic background.