The development and destruction of foreland structures in the South Yellow Sea basin during the collision between the North China and South Block

Abstract

The South Yellow Sea Basin is the extension of the Yangtze Plate, which is regarded as the main part of Lower Yangtze block. The basin had suffered several episodes of tectonic movements, in which the Indosinian movement caused by the collision of the North and South China Plates had modified critically the basin. The Indosinian movement had vital influence on the structural and sedimentary features, basin modification and evolution of the South Yellow Sea Basin. We had analyzed the deformation and the differences in three secondary tectonic units. In the 2D seismic data, the Indosinian movement had resulted in the opposite thrust structures, in which the Northern Depression developed the strongest deformation. Based on the sediment distribution, deformation strength, formation preservation, we had proposed a new foreland basin model for the South Yellow Sea Basin. The Northern Depression could be recognized as orogenic front, the intense compressional structures caused the largest amount of erosion in three units. The Middle Uplift had foreland depositions developed corresponding to the foredeep of foreland basin. The new model has important scientific significance and application value to promote the investigation and exploration of oil and gas resources in this area.