EVOLUTIONARY CHARACTERISTICS OF THE BOUNDARY FAULT OF THE WENXI DEPRESSION,SHANDONG,AND ITS CONTROL ON SEDIMENTARY SAND BODIES

Based on field geological surveys and indoor data processing, the authors have intensively studied the geometric and kinematic characteristics of the major boundary fault (named the Nanliu fault) in the Wenxi depression and the deformation relationship and patterns of the major boundary fault and the secondary structures on the two sides of the major fault, defined the phases of the tectonic deformation and reconstructed the paleotectonic stress field.After their analysis of the basin-controlling effect of the major arcuate boundary, they think that the uneven movements of the boundary fault in different geological periods resulted in changes of the development of sand bodies in the basin with the migration of the subsidence center with time and space.The authors point out that the intersection positions of the arcuate boundary fault and its transverse tensional faults are inlets of ancient and present source materials and sites where sand bodies are developed.