Establishment And Application Of Evaluation Criteria Of Shale Oil And Gas Resources Potential

With escalating energy demand and the continuous consumption of the conventional oil and gas resources,oil and gas supply and demand contradiction have become increasingly prominent.Therefore,unconventional energy are value for people more and more.Shale oil and gas has become the hotspot direction and the reality field of global unconventional oil and gas exploration and development.The occurrence of oil and gas resources in shale which recently can be effectively mined and what is the potential resources and which may always difficult to be effective mining resources,this series of questions directly related to the recent shale oil and gas exploration and deployment.Therefore,we need to have a reasonable standard to guide classification evaluation of the shale oil and gas resources.Based on the system research domestic and international successful acreage shale formation and distribution of oil and gas,this article statistics on China's eastern Songliao,Hailar,Yitong,Jiyang Basin shale geochemical indicators,uses the relationship between the geochemical indicators of a direct reflection of oil content of hydrocarbon source rocks and the TOC,focuses on and discusses shale oil,shale gas resource potential evaluation criteria,and with Yitong basin as target area,through reviews the old well and mud shale geochemical characteristics research,conducted mud shale longitudinal logging recognition of the abundance of organic matter,uses a variety of methods to grading evaluate purposes layers of shale oil and shale gas resource potential.This study provides a theoretical basis and practical significance of the shale oil and gas resource evaluation.The theoretical studies shows:(1)From the inflection point of the curve of the amount of hydrocarbon and organic matter abundance relationship,we use material balance principle to determine the lower limit of the standard of quality source rocks.Determining quality source rocks standard ideas is when organic carbon reach a certain value,expulsion sharply increased,source rock which TOC is higher than the value is a high quality source rocks;the inflection point corresponds to the organic carbon lower limit of the shale enrichment resources;(2)Using directly reflected the shale oil content of geochemical indicators of chloroform asphalt "a",pyrolysis of hydrocarbons(S1)with organic carbon(TOC)relationship,dividing the oil shale resources in the enrichment level.Basing on"three" relations of oil content of shale and TOC,divide spread oil shale resources into resources,inefficient and enrichment resources 3 levels by level of enrichment;(3)Logging data is not only used to identify the TOC of shale,but also be used to calculate the mount of residual hydrocarbon;(4)By diffusion loss of light hydrocarbons and part of the light hydrocarbon dissolved in heavy hydrocarbons in the rock and other factors,pyrolysis S1 and S2 values measured by Rock-Eval,can not represent the original pyrolysis value,we need to restore it.The correction value of heavy hydrocarbon is related to the type of kerogen,and it is usually bigger than 2.The correction value of the light hydrocarbon is related to the thermal evolution degree of shale;(5)The criterion of the effective shale series:the presence of upper barriers,such as 2 meters thick of shale;the sandstone content is less than 1/3 in the shale series,and the continuous thickness of sandstone is less than 2 meters;the total thickness of the shale series is bigger than 30 meters.Applied research shows:(1)Three horizon development mud shale in Nen 1,Qing2-3 and Qingl formations of Southern Songliao Basin.Residual hydrocarbon content data show that the value is relatively high in Nenjiang formations Honggang terrace and Changling fault depression,the value is relatively high in Honggang terrace,Fuxin uplift,Changchunling anticline and Hua prefix wells terrace of Qingshankou formations;the type of organic matter give priority to ???1 in Qingshankou formations,and ???2 in Nenjiang formations;maturity indicators show that the type give priority to low mature-mature.(2)Review results of the old wells of the Southern Songliao Basin purpose layer overall express that the shale's high acoustic,high neutron,low-density response is obvious;according to the review results of the old wells,favorable areas of the Southern Songliao Basin shale oil and gas are mainly distributed in Honggang,Changling,Fuxin uplift and part of Wangfu area,there is a correlation between its distribution area and organic matter content distribution;The fractured reservoir of Fuxin uplift Qing 3 formations isn't self-generated and self-stored,does not belong to the shale oil and gas areas;(3)Log geochemistry show that shale oil primary resources are mainly distributed in Nen 1,Qing 1 and the lower part of Qing 2 formations,and the distribution area of primary shale oil is limited,it is mainly distributed in Honggang,Changling and Fuxin uplift;(4)SEM show that Southern Songliao Basin shale porosity have intergranular pore,intragranular pore,dissolved pore,it is mainly intergranular pore;we can see secondary quartz,and commonly see illite;though the secondary quartz reduce the reservoir space,conducive to fracturing treatment,high content of illite make the percolation capacity worse;(5)The CT tests show that 50 ?m or less pore space are the main reservoir space of shale oil and gas,with the increase of the organic maturity,not only promote shale generate hydrocarbon,but also form large number of micron and nanoscale pores and micro-cracks;(6)The total amount of shale oil resources of the Southern Songliao Basin are 643.08 billion tons,where primary resources is 14.955 billion tons,and mainly distribute in Qing 1,Qing 2 and Nen 1 formations.