Tectonically controlled evolution of the Yellow River drainage system in the Weihe region, North China: Constraints from sedimentation, mineralogy and geochemistry

摘要

This study investigated the evolution of the middle reach of the Yellow River by examining the latest Cenozoic (similar to 5.0-0.15 Ma) sedimentary history of the Weihe and Sanmenxia basins in the Weihe region of North China. Although the development of the two basins and the evolution of the Yellow River have long been related to the rapid uplift of the Tibetan Plateau, the relationship between the landform evolution and regional tectonics is still poorly understood. Here, we report the results of a detailed study on sedimentation and provenance of the two basins and their spatial and temporal relationships to regional fault development. The results show that the two basins were possibly originally isolated from each other, between similar to 5 Ma and similar to 2.8-2.6 Ma, but later connected by the Yellow River at similar to 2.8-2.6 Ma. This process is recorded in the coarsening-upward sequence of the Weihe Basin strata and the coeval fining-upward succession of the Sanmenxia Basin strata. At similar to 1.0 Ma, the Sanmenxia Basin strata developed a coarsening-upward trend, which we interpret as an indication of the formation of the Yellow River in the region. In addition, changes in the drainage system at similar to 2.8-2.6 Ma and at similar to 1.0 Ma have been recorded as dramatic provenance changes in the sediments of the Sanmenxia Basin.