Ancient Landform Reconstruction of the Bayanhushu Depression

Abstract

Paleogeomorphology represents the outcome of combined tectonic processes such as crustal movements, volcanic activity, and
earthquakes, while stratigraphic morphology undergoes comprehensive alterations due to tectonic activity. Tectonic activity plays a dominant
role in the distribution and migration of hydrocarbon resources. Therefore, paleogeomorphological reconstruction of the study area is highly
advantageous for hydrocarbon exploration. Through paleogeomorphological reconstruction of the Nantun Formation in the Bayanhushu De
pression and investigation of its tectonic evolution, the following conclusions are drawn: The Bayanhushu Depression exhibits an overall axial
northeast-trending, west-block-fractured, east-block-overthrust fault-bust structure. The basin exhibits north-south segmentation and east-west
zoning. The Bayanhushu Depression underwent stages of rift depression and tectonic collapse. The Tongbomei Formation deposition corre
sponds to the initial rift depression phase, while the Nantun Formation and Damoguahe Formation deposition periods represent the rift expan
sion phase. The Yimin Formation deposition marks the rift collapse and contraction stage, followed by the subsequent depression phase.