Issue Of Quaternary Sealevel Rising And Empirical Study

Based on a lot of domestic and foreign references related to Quaternary high sea surface,the paper summarized the age,area,and high sea surface height of Quaternary high sea surface in a systematic and detailed way.According to the summary,most of domestic and foreign scholars' research on Quaternary high sea surface focused on the Holocene.Due to old age,it was very difficult to preserve the complete ancient landform relics in the Pleistocene.So they rarely studied the high sea surface in the Pleistocene.The paper took the Liaodong Peninsula as an example,proposed to prove whether the high sea surface existed or not through the distribution height of tertiary red weathering crust and hoped to enrich research on Quaternary high sea surface.The Liaodong Peninsula had been in the terrestrial environment for a long time before the loess in Lishi was accumulated.After planation surface and humid climate conditions in the long-term geological period,it formed a broad peneplain.Among them,the Sinian and Cambrian strata were directly first exposed to the surface in part of the area.And other parts of the area were covered with tertiary andQuaternary loose deposits.Until the late tertiary,the upper limestone distribution area began to develop thick red weathering crust.Therefore,at present,a set of the late tertiary red weathering crust has been widely distributed in the Liaodong Peninsula in northern China.After a field survey,the paper selectively analyzed the age of thick red weathering crust in around Shicao Village and urban stratigraphic section in the Liaodong Peninsula.Loose debris of tertiary red weathering crust was completely preserved in urban hilltop coastal area,about 1.5m far from the high tide level.Loose debris of weathering curst that failed to form rock had relatively loose performance and strong ability to resist erosion.The reason why it could be preserved up to now was that it did not suffer strong marine erosion.Therefore,the paper thought that the preserved height could be regarded as a symbol of the highest sea surface since the formation of red weathering crust.In the experimental center of Liaoning Normal University,the author made a comparison analysis of geochemical characteristics of red weathering crust in two areas through ZSX Prinmus II spectrometer produced by Japanese Rigaku Company,calculated that the formation time of red weathering crust was not less than 10.87 million years,that is,dated from middle Miocene or earlier combine with the maximum thickness of the residual red weathering crust within the research area.According to this,it can be considered that the current sea level height is close to the highest sea level height since the late tertiary.And the problems related to tertiary and Quaternary high sea level mentioned in the previous literatures are open to question.