Favorable Area Selection And Development Strategy Of Shale Gas In Chongqing

The shale gas resource potential in Chongqing district is enormous,but because of low abundance,dense reservoir,strong heterogeneity and other reasons,the geological risk of development shale gas is huge,causing this kind of projects difficult to achieve business development.Evaluation method on shale gas block in our country,from the qualitative evaluation to quantitative evaluation method,qualitative evaluation method mainly apply multi-factor overlay technique,quantitative evaluation method involves setting evaluation standard and evaluation index weight assignment,after determining weight no matter how change parameter values,always maintain constant weight value,the fixed weights model can't reflect the difference influence on the evaluation results of parameter values.Therefore,the introduction of variable weight assignment method can overcome the defects of each evaluation index in the evaluation process with only one fixed weight,so as to achieve the dynamic assignment of weights.According to the Chongqing area shale gas exploration and development practice,this method is applied to shale gas in the Chongqing area in the evaluation,comprehensive evaluation of the variable weight shale gas blocks value(grading value),comparative evaluation value and evaluation standard,the shale gas blocks in Chongqing area for different types of classification,and according to the characteristics of various types the proposed exploration and development suggestions.Finally,in order to promote the orderly and reasonable development of shale gas in Chongqing area,the paper analyzes the present situation of exploration and development of shale gas in Chongqing area by using SWOT analysis method,and puts forward some suggestions for the development of shale gas industry in Chongqing area.The detailed results as follows:1.The evaluation index system of shale gas was constructed,which is based on the influence factors of shale gas exploration and development.The index system includes three first level indicators: resource conditions,development conditions and market conditions.Resource conditions including organic matter abundance,organic matter maturity,gas content,the thickness of shale four secondary indicator;development conditions include shale layer depth,terrain conditions,developing water accounted for the proportion of the total water use and development of water accounts for the proportion of water available and formation dip five secondary indicator;Market conditions consi-dering the per capita GDP,urbanization rate two secondary indexes.2.According to response evaluation index for the evaluation of each index constituency punishment incentive interval,weight change trend in the period of the penalty incentive index and common function change for comparison,select the same trend as a function of the establishment of mathematical model of state variable weight function,the model has more than the degree of punishment incentive degree characteristics the.According to the state values of the ideal evaluation unit and the corresponding variable weights,the weights are obtained.3.If result of constant weight evaluation is the basis for the development sequence of shale gas in every block of Chongqing area,It should be Fuling,Pengshui,Wulong,Qianjiang,Youyang,Xiushan as the order of development shale gas;If the results of variable weights comprehensive evaluation of each block are taken as the basis for the development of shale gas in Chongqing area,It should be Fuling,Wulong,Pengshui,Qianjiang,Youyang,Chengkou and Xiushan as the order of development shale gas;According to the result of constant weight evaluation,all blocks have exploration potential,Fuling is extremely favorable area,Chengkou,Wulong,Pengshui are favorable area,Qianjiang,Xiushan,,Youyang is less favorable for the exploration area,no block in the area of non favorable;According to the result of variable weight comprehensive evaluation,Qianjiang,Youyang and Xiushan are in the non favorable area of exploration.Obviously,the result of variable weight evaluation is more consistent with the exploration and development of shale gas in Chongqing area and the actual work arrangement.4.Take Chengkou block as an example to analyze some comprehensive evaluation with variable weight comprehensive evaluation results the reasons of the differences.Think due to resource indicators in motivating the whole range,according to the characteristics of state variable weight function,in incentive interval variable has heavy relatively often has small changes,so the resource conditions of overall value changed little;Development conditions of state variable weight of each index in the difference to be markedly,JingBian right after processing,the terrain conditions for the development of one of the biggest influence factors,and terrain conditions after the normalization of index and special low,making smaller value development conditions;Market conditions of two indicators are in a strong punishment range,the urbanization rate of punishment punishment than per capita GDP level is high,leading to the final value decrease market conditions.5.The block types in the study area are divided into 4 categories,based on the results of the variable weight comprehensive evaluation,: block type I is an excellent resource conditions and development conditions of the block;II class resource condition is excellent,but the development of the poor conditions of the block;the III class for resources and good development conditions of the block;IV class resource the block is not ideal.Comprehensive evaluation results show that the Fuling I block,II block Chengkou,Wulong and Pengshui belonged to the IV block,Qianjiang,Xiushan,Youyang IV block.According to the different situations of each block,this paper puts forward the corresponding exploration and development strategy.The resource condition is not too ideal block,exploration and development risks,in order to avoid risks,that put a small amount of workload or suspend the work of exploration and development;the resources and conditions for the development of a good block,should strengthen the research of drainage technology,and explore to reduce costs through large-scale development and intensive management mode for the next.The breakthrough of development;good resource conditions,the poor condition of the block,should strengthen the research of drilling completion technique under complicated geological conditions,and should strengthen the management of water resources,optimize the allocation of water resources,water is strictly prohibited in medium and small rivers in the annex;breakthrough has been made on the block,the construction of the test area should promote the block of shale gas exploration,summed up the mode of development,promote the application of technology demonstration,to explore a set of consistent with the geological characteristics of Chongqing area of shale gas exploration and development management Pattern.6.Some suggestions are put forward for the development of shale gas industry in Chongqing area.Such as a clear policy direction to explore new ideas;drop cost;cultivate the market for shale gas exploration and development technical services;construction of the evaluation index of shale gas development environment,strengthen environmental supervision to promote the development of shale gas;Fuling shale gas exploration area construction,summarizes the mode of development,promote the application of technology demonstration,to explore a set of consistent with the geological characteristics of Chongqing area shale gas exploration and development management mode.