渤中坳陷中部地区构造应力场光弹模拟实验研究

Photoelastic modeling of the tectonic stress field in the central part of the Bozhong depression

在对渤中地区沉积构造详细分析的基础上,明确了其中部地区断裂的分布特征,采用以E44-6101型环氧树脂为基体,顺丁烯二酸酐为固化剂,邻苯二甲酸二丁脂为增塑所配制的材料制成渤中中部地质结构模型,对渤中坳陷中部地区构造应力场进行了光弹实验模拟,再现了近北北东向和近东西向断裂在晚近构造格局下的应力状态及分布。试验证明,在构造应力场的作用下,油气往往由高应力值区向低应力值区迁移,而且渤中地区自新近系以来,最大主压应力方向比较稳定。基于试验结果的分析,对北北东向和近东西向两组断裂在晚近应力场的作用下的构造特征及其对油气的控制作用进行讨论。由于渤中坳陷是中国的油气主要产地,通过研究盆地构造应力场的分布,可为盆地的油气勘探和开发提供依据。

Based on an intensive analysis of the sedimentary and tectonic evolution in the central part of the Bozhong depression, the paper reveals the characteristics of faults and their distribution in the area. A geological structural model of the central part of the Bozhong depression is constructed using E44-6101 type epoxy resin as matrix, maleic anhydride as a condensate and dibutyl phthalate C.P. as plasticizer, and experimental photoelastic modeling is performed for the tectonic stress field of the study area. Then the stress state and distribution of the nearly NNE-and nearly E-W-trending faults in the Neoid tectonic framework are reproduced. The experimental results show that under the action of the tectonic stress field petroleum usually migrates from the high-stress value zone to low-stress value zone and that the direction of the maximum principal compressional stress has been relatively stable in the Bozhong area since the Neogene. Based on an analysis of the experimental results, the paper discusses the characteristics of the NNE and nearly E-W sets of faults under the Neoid stress field and their controls on petroleum. As the Bozhong depression is China＇s major petroleum production area, the study of the distribution of the tectonic stress field of the basin can produce a basis for petroleum exploration and development of the basin