From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development a...From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development are determined, and the evaluation index system of geological sweetspot for CBM development is established. On this basis, the fuzzy pattern recognition(FPR) model of geological sweetspot for CBM development is built. The model is applied to evaluate four units of No.3 Coal Seam in the Fanzhuang Block, southern Qinshui Basin, China. The evaluation results are consistent with the actual development effect and the existing research results, which verifies the rationality and reliability of the FPR model. The research shows that the proposed FPR model of geological sweetspot for CBM development does not involve parameter weighting which leads to uncertainties in the results of the conventional models such as analytic hierarchy process and multi-level fuzzy synthesis judgment, and features a simple computation without the construction of multi-level judgment matrix. The FPR model provides reliable results to support the efficient development of CBM.展开更多
根据地质、地化、测井资料,明确了页岩油富集主控因素是泥页岩岩相、页岩油的可动性、泥页岩裂缝和异常压力等要素。根据页岩油富集主控因素建立了页岩油甜点评价方法。不同岩相它的储集性和含油性不同,因此岩相可由它的储集性和含油性...根据地质、地化、测井资料,明确了页岩油富集主控因素是泥页岩岩相、页岩油的可动性、泥页岩裂缝和异常压力等要素。根据页岩油富集主控因素建立了页岩油甜点评价方法。不同岩相它的储集性和含油性不同,因此岩相可由它的储集性和含油性来表征。用AC曲线和R4曲线评价页岩岩相的储集性和含油性。页岩油的可动性可由S_1、S_1/TOC和页岩油黏度综合评价;S_1>2 mg/g,S_1/TOC>10%,黏度<10 m Pa·s的页岩油可动性好;泥页岩裂缝可由岩心、常规测井和成像测井综合判识;压力系数大于1.2的区域是页岩油发育的有利区。最后,根据页岩油主控因素综合确定了济阳坳陷页岩油甜点分布的有利地区,为济阳坳陷下一步页岩油勘探指明了方向。展开更多
As several major new gas discoveries have been made recently in the Lower Cambrian Longwangmiao Fm reservoirs in the Leshan-Longnǚsi Palaeohigh of the Sichuan Basin,a super-huge gas reservoir group with multiple gas ...As several major new gas discoveries have been made recently in the Lower Cambrian Longwangmiao Fm reservoirs in the Leshan-Longnǚsi Palaeohigh of the Sichuan Basin,a super-huge gas reservoir group with multiple gas pay zones vertically and cluster reservoirs laterally is unfolding in the east segment of the palaeohigh.Study shows that the large-scale enrichment and accumulation of natural gas benefits from the good reservoir-forming conditions,including:(1)multiple sets of source rocks vertically,among which,the high-quality Lower Paleozoic source rocks are widespread,and have a hydrocarbon kitchen at the structural high of the Palaeohigh,providing favorable conditions for gas accumulation near the source;(2)three sets of good-quality reservoirs,namely,the porous-vuggy dolomite reservoirs of mound-shoal facies in the 2nd and 4th members of the Sinian Dengying Fm as well as the porous dolomite reservoirs of arene-shoal facies in the Lower Cambrian Longwangmiao Fm,are thick and wide in distribution;(3)structural,lithological and compound traps developed in the setting of large nose-like uplift provide favorable space for hydrocarbon accumulation.It is concluded that the inheritance development of the Palaeohigh and its favorable timing configuration with source rock evolution are critical factors for the extensive enrichment of gas in the Lower Cambrian Longwangmiao Fm reservoirs.The structural high of the Palaeohigh is the favorable area for gas accumulation.The inherited structural,stratigraphic and lithological traps are the favorable sites for gas enrichment.The areas where present structures and ancient structures overlap are the sweet-spots of gas accumulation.展开更多
基金Key Project of China National Natural Science Foundation (42230814,52234002)Research Program Foundation of Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences),Ministry of Education (TPR-2022-17)。
文摘From the perspective of geological zone selection for coalbed methane(CBM) development, the evaluation parameters(covering geological conditions and production conditions) of geological sweetspot for CBM development are determined, and the evaluation index system of geological sweetspot for CBM development is established. On this basis, the fuzzy pattern recognition(FPR) model of geological sweetspot for CBM development is built. The model is applied to evaluate four units of No.3 Coal Seam in the Fanzhuang Block, southern Qinshui Basin, China. The evaluation results are consistent with the actual development effect and the existing research results, which verifies the rationality and reliability of the FPR model. The research shows that the proposed FPR model of geological sweetspot for CBM development does not involve parameter weighting which leads to uncertainties in the results of the conventional models such as analytic hierarchy process and multi-level fuzzy synthesis judgment, and features a simple computation without the construction of multi-level judgment matrix. The FPR model provides reliable results to support the efficient development of CBM.
文摘根据地质、地化、测井资料,明确了页岩油富集主控因素是泥页岩岩相、页岩油的可动性、泥页岩裂缝和异常压力等要素。根据页岩油富集主控因素建立了页岩油甜点评价方法。不同岩相它的储集性和含油性不同,因此岩相可由它的储集性和含油性来表征。用AC曲线和R4曲线评价页岩岩相的储集性和含油性。页岩油的可动性可由S_1、S_1/TOC和页岩油黏度综合评价;S_1>2 mg/g,S_1/TOC>10%,黏度<10 m Pa·s的页岩油可动性好;泥页岩裂缝可由岩心、常规测井和成像测井综合判识;压力系数大于1.2的区域是页岩油发育的有利区。最后,根据页岩油主控因素综合确定了济阳坳陷页岩油甜点分布的有利地区,为济阳坳陷下一步页岩油勘探指明了方向。
文摘As several major new gas discoveries have been made recently in the Lower Cambrian Longwangmiao Fm reservoirs in the Leshan-Longnǚsi Palaeohigh of the Sichuan Basin,a super-huge gas reservoir group with multiple gas pay zones vertically and cluster reservoirs laterally is unfolding in the east segment of the palaeohigh.Study shows that the large-scale enrichment and accumulation of natural gas benefits from the good reservoir-forming conditions,including:(1)multiple sets of source rocks vertically,among which,the high-quality Lower Paleozoic source rocks are widespread,and have a hydrocarbon kitchen at the structural high of the Palaeohigh,providing favorable conditions for gas accumulation near the source;(2)three sets of good-quality reservoirs,namely,the porous-vuggy dolomite reservoirs of mound-shoal facies in the 2nd and 4th members of the Sinian Dengying Fm as well as the porous dolomite reservoirs of arene-shoal facies in the Lower Cambrian Longwangmiao Fm,are thick and wide in distribution;(3)structural,lithological and compound traps developed in the setting of large nose-like uplift provide favorable space for hydrocarbon accumulation.It is concluded that the inheritance development of the Palaeohigh and its favorable timing configuration with source rock evolution are critical factors for the extensive enrichment of gas in the Lower Cambrian Longwangmiao Fm reservoirs.The structural high of the Palaeohigh is the favorable area for gas accumulation.The inherited structural,stratigraphic and lithological traps are the favorable sites for gas enrichment.The areas where present structures and ancient structures overlap are the sweet-spots of gas accumulation.
