Structural Features And Optimized Oil-bearing Area Forecast Of Mesozoic And Cenozoic Erathem In Wushi Sag

Wushi Sag is locating in the northwest of Tarim Basin, is shuttle intermountain deep of Mesozoic and Cenozoic Erathem. As the northwest extend of Kuche basin, Wushi Sag, especially its eastern part, presents Mesozoic Erathem of great depth and distribution, which develops good reservoir-capping equipment in Kuche region. Well Wucan 1 and Shenmu 1 have attained high yield flow of hot gas, so Wushi Sag has good exploration prospect.On analyzing the tectonic background of Wushi Sag, ensuring the structural framework, especially researching the features and the distribution of faults, and studying the structural evolvement features, we get deep recognization of sub-structural belt distribution in this area, and propose target evaluating of oil-bearing traps.We finish integrated explanation through by the late gravity, magnetic and electric, these non-seismic materials; complete geological explanation of seismic profiles, basin analysis, tectonic equilibrium profiles, Landmark software study; based on tremendous two-dimension seismic profiles, we carry on structural explanation, and combined with several wells, we strictly mark the seismic strata and explain the primary framework profiles to details.After the seismic stratum explanation, we confirm that Wushi Sag exist Pre-Mesozoic Erathem base, Mesozoic Erathem and Cenozoic Erathem, three structural layers, and develop different structure systems, and its structural evolvement saw Pre-Mesozoic base developing stage, Mesozoic block uplift developing stage, and Tertiary block-nappe structure developing stage, three tectonic history stages. Wushi Sag is a superimposed basin of two stage foreland basins of Mesozoic and Cenozoic. There are six fault systems: north bound fault system, northern fault system, southern fault system, eastern strike slip fault system and western Cenozoic fault system. The south bound fault of Wushi Sag is Gumubiezi fault, which is a system of several reverse faults oblique arranged and step rose to Wensu Uplift. Newly defined Wushi Sag concludes northern foreland structure belt, western slope belt, middle deep and southern block dome belt. And the late west part of Wushi Sag is divided into Wensu Uplift, because of their Similary.The research defines farther the structural feature of Yilake structure, proposes two optimized oil-bearing traps: South Tianshan foreland structure belt and Xigua structure. South Tianshan foreland develop series of anticlines oblique arranged and en echelon presented to orogenic belt, and Shenmu 1 structure is one of these and has got big breakthrough. Xigua structure is a stratum-structure trap, locating in the most west of southern block uplift, and itssouth nearly neighboring Gumubiezi fault.