Shale Gas Evaluation And Evaluation Methods Research In YuanBa Block Northeastern Sichuan

YuanBa block is located in the northeast part of Sichuan Basin. The mining area is3251.48km2, of which2514km2in western YuanBa block.The surface outcrops of theLower Cretaceous strata. The area is in the position of the structure transition of multiplebarrier, which has undergone multiphase tectonic activity overprinting since Mesozoic,Cenozoic. It has drilled50wells, and obtained industrial oil and gas in the ZiLiuJingformation of Jurassic, proved that the area has good shale gas potential.This paper is based on the previous research, systematic analysis of the oil geologicalconditions of DaAnZhai section of YuanBa block. According to the exploration degree ofEast and west two blocks of different in DaAnZhai section, combining the volume methodand analogy method,calculate the amount of resource and Evaluate the oil and gas resourcepotential, Predicted favorable zones for exploration and decision-making.By using SGRE1.2software to calculate the the western YuanBa block resources withthe volumetric method. The total resource in this area is about933.746billion square and theresource abundance, average is about4.33billion square per kilometer. Using the analogymethod to calculate the amount of resources in eastern YuanBa block. The total resource inthis area is about1544.13billion square and the resource abundance, average is about1.89billion square per kilometer.Summarizes the results of previous research and the question on encounter resourcesevaluation methods, proposeing the improvement suggestions in the future includingMulti-site analytical experiments, improved calculation model and the fitting formula,detailed interpretation of the weight of analog and build more analogy standard area.According to the basic geological conditions and resources distribution characteristics ofYuanBa area,thinks that the line of YuanBa223-YuanBa101,-yuanBa1-YuanBa11welland the area between the front-line of YuanBa9-the Yuanba5-YuanBa3-YuanBa4well isthe favorable area for shale gas exploration which obtain higher production capacity. The areais shallow lake sedimentary with thick mud shale.The TOC is generally in the range of1.2%to1.3%, It has more limestone and sandstone interbed in mud shale system, which isconducive to the formation and transformation of micro-cracks in the layer.