Exploration Potential Analysis Of The Member 2 Of Jurassic Sangonghe Formation In Zhuang 6 Wellblock,Well Pen-1 Western Depression,Junggar Basin

Abundant lithologic and structural-lithologic reservoirs have been found in Sangonghe Formation in the Qianshao area of the Northeast gentle slope belt in the northeast of Well Pen-1 Western Depression in Junggar basin,showing a major breakthrough in oil and gas exploration and shows the exploration potential of Sangonghe Formation in the gentle slope zone.However,Well Zhuang-6 block,located in a similar structure,has few basic data,weak geological research and unclear oil and gas exploration potential.Thus,it is of great significance to carry out structural analysis,preliminary sedimentary reservoir evaluation and trap evaluation of Sangonghe Formation in the Zhuang 6 wellblock,and to clarify exploration potential for further oil and gas exploration in the study area.The sedimentary facies types of Sangonghe Formation in the Zhuang 6 wellblock are analyzed under the sedimentary background of Well Pen-1 Western Depression.The structural interpretation is carried out with the help of seismic attributes such as ant body,and the fault development mode is analyzed.The sand body of the second sand group is identified by natural gamma waveform inversion,and the trap is identified by combining the structure and sand body.Based on the analysis of typical reservoirs in Qianshao area,the hydrocarbon accumulation model and exploration potential of Sangonghe Formation in the Zhuang 6 wellblock are determined.The results show that: the first sand group of Sangonghe Formation in the Zhuang 6wellblock is Braided-river delta subfacies with thick sandstone,and the second sand group reservoir is sandy clastic flow deposit.The thickest sand body is in the northwest of well Fang004 and the west of well Fang 003,with the thickest up to 14 m and pinching out to the northeast.The continuous structural warping after the deposition of Sangonghe formation makes the dip change from northeast to southwest,which creates conditions for the development of lithologic traps.The Sangonghe Formation in the study area has successively developed 7 groups of NWW and 5 groups of NNE-trending two-phase echelon fault belts.The faults in the two directions intersect each other,forming fault block trap and fault-lithologic trap,and some faults connect with Permian oil source.There are 12 traps in the study area,including fault block trap,lithologic updip pinchout trap and fault-lithologic trap,with a total area of 15.36 square kilometers and a predictable reserve of 3.0269 million tons.However,as a whole,the area of a single trap in the second sand group of the Sangonghe Formation in the Zhuang 6 wellblock is small,the reservoir quality is relatively poor,and the exploration potential is relatively low.Therefore,trap 2,trap 3 and trap 10 are selected in the study area as the next exploration direction.