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通过新近纪断裂体系和底辟构造特征综合分析认为,底辟构造、高角度的断裂和垂向裂隙系统构成了南海北部神狐海域天然气水合物成藏的主要流体运移体系.神狐海域断层发育,可分为晚中新世活动的NW(NNW)向断层和上新世以来活动的NE(NNE)断层两组.NE向断层活动强度小,规模大,从下至上切穿上新世以来沉积层,组成高角度断裂和垂向裂隙系统.底辟构造在地震剖面上呈直立的、上小下大的烟囱状通道,局部横向扩张呈囊状、花状,形成大型的反射模糊带.底辟构造的发育在上覆沉积层产生了树枝状、似花状组合形态的高角度断裂和垂向裂隙系统,构成了良好的流体运移通道和疏导体系.当富含甲烷气体的流体通过底辟构造、断裂及裂隙系统垂向或侧向运移时,在合适的温压条件下形成天然气水合物.
Based on the comprehensive analysis of the Neogene fault system and diapir structural features, it is considered that the diapir structures, high-angle fractures and vertical fracture systems constitute the major fluid migration system for gas hydrate accumulation in Shenfo area, northern South China Sea. (NNW) faults and NE (NNE) faults that have been active since the Pliocene. The NE-trending fault activity is small, large-scale and cut through the Pliocene from the bottom up Since the sedimentary layer, composed of high-angle fracture and vertical fracture system.The diapir structure in the seismic section was upright, small chimney-shaped channel, the local lateral expansion was cystic, flower-like, forming a large reflection fuzzy band The development of the diapir structure resulted in a dendritic, flower-like combination of high angle fractures and vertical fracture systems in the overlying sediments that formed a good fluid migration pathway and drainage system.When methane-rich fluids Natural gas hydrate is formed under appropriate temperature and pressure conditions through vertical and lateral migration of diapir structures, faults and fractured systems.