A STUDY ON THE BOUNDARY FEATURE OF QUATERNARY AND NEOGENE IN QINWANGCHUAN BASIN

Based on the latest research results on geological structure, earthquake and investigation in Lanzhou New Area, combined of the environmental geological problems that collapses, landslides, debris flow, instability slope and salinization have been developing in Lanzhou new areas during the process of urbanization and other serious threats to the city, by means of the existed classifications of topography and divisions of rocks and soils type, and according to the rules of similarity and differences for classifying the engineering geological conditions, the urban engineering geological conditions in Lanzhou new area were studied by dividing the whole new area into 2 kinds of zones-soil body stability and by further dividing them into three sub zones, with the conclusion that new area could be divided into accumulation basin district area of engineering geology and engineering geology area at the two districts. Among them, the hills of engineering geology is divided into stable, relatively stable, poor stability three sub zones. Engineering geology accumulation basin area and the stability of engineering geology area at the rock(soil) mass good stability and good engineering geological conditions. Relatively stability of the engineering geology area at the rock(soil) mass stability is better. The engineering geological condition is good, and can be used as the focused development and construction areas in Lanzhou new area in the future.