断陷盆地油气资源丰富，在石油工业中具有重要地位。对盖层构造样式影响因素的研究，可为断陷盆地油气勘探和开发提供更多的理论依据。采用离散元数值模拟的方法，研究了在双向伸展条件下，韧性基底黏度对盖层构造样式的影响。结果表明：在不同基底黏度下，形成的盆地形态相似，均发生均匀伸展，盆地内部断层的断距相差不大；沉降中心始终位于中间位置，在伸展过程中不发生迁移；在充分伸展的条件下，韧性基底黏度越大，生成的断层数量越多。结合实验模拟结果和琼东南盆地长昌凹陷剖面特征，认为大地热流值较大时，基底黏度较小，所生成的断层数量较少；反之，大地热流值较小时，基底黏度较大，所生成的断层数量较多。

Rifted basins are rich in oil and gas resources，and play an important role in petroleum industry. This thesis，which focuses on the influencing factors of structure styles of a sedimentary cover，can provide more theoretical basis for oil and gas exploration and development in rifted basins. Many researchers have been studying the influencing factors such as geometric conditions of the basin boundary，pre-existing faults in the basement，basement properties (ductile or rigid)，extension rate，syndeposition and so on. However，fewer study have been carried out on the influence of viscosity of ductile basements on structure styles of a sedimentary cover. In this study，the effects of viscosity of ductile basements on the structure styles of a sedimentary cover are systematically investigated by using discrete element modeling. Model results show that in models with different viscosity of ductile basements，the morphology of basins is similar，all are homogeneously extended. The fault distance of different models is not much different. The center of settlement is always in the middle and does not migrate during extension. The greater the viscosity of the ductile substrate，the greater the number of faults generated. According to the experimental simulation results and the profile characteristics of Changchang Sag in Qiongdongnan Basin，when the terrestrial heat flow value is large，the basement viscosity is small and the number of faults generated is small; conversely，when the terrestrial heat flow value is small，the basement viscosity is large and the number of faults generated is large.