The Design and Realization of the Forward Model for the Simulation of the Foreland Basin Flexure Subsidence Process: A Case Study of Design and Realization of the Tertiary Kuqa Foreland Depression
前陆盆地挠曲沉降正演模型的设计与实现——以库车古近纪陆内前陆坳陷沉降分析为例

Based on the 2D thin board elastic flexure model and simplified and optimized model parameters in the visual C ++ 6.0 environment and using the visual window design idea, the authors built the flexure subsidence dynamic modeling software of foreland basin and applied it to the analysis of the compression flexure subsidence process of Tertiary Kuqa foreland basin. The modeling result shows that the whole subsidence curve and subsidence rate of Tertiary Kuqa foreland basin exhibit an upward convexity shape, indicating a typical flexure subsidence characteristic. According to variation of the subsidence rate, the whole subsidence process may be divided into four phases, corresponding to four tectonic sequence phases respectively. There exist different subsidence characteristics in different phases, with a period of basin upheaval and quiescence of the tectonic activity existent between two adjacent phases which suffered extensive erosion and formed unconformity. Through the time-dispersion of the depositional process and the exact setting up of the tectonic load of different segments, the forward model can exactly restore the subsidence rate and subsidence curve, overcoming the shortcomings of the reward backstripping model which fails to accurately restore the sequence-scale subsidence process due to the impossibility of obtaining the accurate geological age for every surface.