陆相盆地古源-汇系统定量重建、级次划分及耦合模式

Quantitative reconstruction， hierarchical division and coupling mode establishment for ancient source-to-sink systems in continental basins

朱红涛 徐长贵 杜晓峰 刘强虎 孙中恒 曾智伟

Hongtao ZHU Changgui XU Xiaofeng DU Qianghu LIU Zhongheng SUN Zhiwei ZENG

陆相盆地古源-汇系统定量重建、级次划分及耦合模式是还原深时盆地剥蚀和沉积过程的重要研究内容。陆相盆地古源-汇系统物源区定量重建难点主要包含古地貌重建和古水系重建。古地貌重建新技术的发展提出了基于剥蚀区、超剥区（剥蚀和超覆作用共同作用区）和超覆区为框架，残余地貌重建、差异沉降校正、超剥区恢复、剥蚀区恢复和沉积古地貌恢复流程的“三区五步”恢复方法。古水系重建方面提出了基于ArcGIS系统的古水系定量恢复和拾取方法。陆相盆地古源-汇系统级次划分的代表方法是“三线三级”法，关键是拾取分水岭、分水线和脊线，进而划分一级、二级、三级古源-汇系统。基于重建的古源-汇系统物源区流域单元与沉积区沉积体的面积、形态组合、配置关系，建立了“哑铃型”“球拍型”“奖杯型”和“标枪型”4种古源-汇系统耦合模式。研究成果对古源-汇系统定量化研究和勘探目标评价、预测具有一定的参考价值。

Quantitative reconstruction， hierarchical division and coupling mode establishment are important means to restore the erosion and sedimentation processes for depth-time ancient source-to-sink systems in continental basins. The main difficulties in quantitative reconstruction of provenance lie in paleo-geomorphology reconstruction and paleo-drainage reconstruction. New techniques for paleo-geomorphology reconstruction use a “three-zone and five-step” restoration method based on the framework of denudation， overlap-denudation and overlap zones as well as steps of residual geomorphology reconstruction， differential subsidence correction， overlap-denudation zone restoration， denudation zone restoration and depositional paleo-geomorphology restoration. In terms of paleo-drainage system reconstruction， a quantitative restoration and picking method is resorted to based on the ArcGIS system. The division of ancient source-to-sink systems in continental basins is usually realized by using the “three-line and three-level” method， of which， picking up watersheds， water dividing lines and ridge lines are very critical before a further division of first-order， second-order， and third-order source-to-sink systems. According to the area， geometric configuration and coupling relationship of the drainage unit and sedimentary body within the reconstructed ancient source-to-sink system， this paper puts forward four types of source-sink coupling modes， i.e.， “dumbbell”， “racket”， “trophy” and “javelin” modes， and thus may serve as a valuable reference for quantitative study of source-to-sink system and prediction of deep exploration targets.

10.11743/ogg20230302