川西北地区中泥盆统观雾山组储集层特征、控制因素与演化  

Characteristics,controlling factors and evolution of the Middle Devonian Guanwushan Formation reservoirs in Longmenshan area,northwestern Sichuan,China

作　　者：熊连桥[1,2] 姚根顺 倪超 熊绍云 沈安江 周刚 郝毅 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油杭州地质研究院,浙江杭州310023 [3]中国石油集团碳酸盐岩储层重点实验室,浙江杭州310023 [4]中国石油西南油气田公司勘探开发研究院,四川成都610041

出　　处：《天然气地球科学》2017年第7期1031-1042,共12页Natural Gas Geoscience

基　　金：国家科技重大专项"大型油气田及煤层气开发"(编号:2016ZX05004-002);中国石油集团科技重大专项"深层油气勘探开发关键技术研究"(编号:2014E-32-09)联合资助

摘　　要：川西龙门山地区中泥盆统观雾山组油气勘探获得突破,但对储集层尚无系统研究。通过野外露头、岩心、薄片、阴极发光资料,结合岩石物性分析,对龙门山地区观雾山组储集层特征、控制因素和储集层演化过程进行深入研究。结果表明,观雾山组储集层岩性主要为砾屑白云岩、生物白云岩、生物碎屑白云岩和晶粒白云岩,储集空间以残余粒内溶孔、晶间溶孔、大型溶孔为主,构造裂缝发育,平均孔隙度约为2.85%,储集层主要为礁滩体白云岩裂缝—孔洞型储集层。储集层形成受礁滩体、白云石化作用和溶蚀作用控制,礁滩体是储集层发育的地质基础,白云石化作用是储集层发育的必要条件,溶蚀作用是储集层发育的关键因素,构造作用推动储集层最终形成。储集层经历了3个演化阶段,沉积、白云石化及溶蚀作用奠定了储集空间类型,构造作用改善储集层物性,沥青充填使储集层物性变差。基于储集层主控因素,预测剑阁—江油—绵阳地区古地貌高点的白云岩礁滩体是有利储集层发育区,油气勘探有望取得新突破。Hydrocarbon exploration has been made in the Middle Devonian Guanwushan Formation（D_2g）in the Longmenshan area.However,studies on reservoirs are rare.In order to make a detailed study on the characteristics,controlling factors and evolution of the reservoirs in the D_2g in northwestern Sichuan Basin,outcrops,cores,thin sections,cathode luminescence,and log data were analyzed.The result shows that the reservoirs in the D_2g are dominantly comprised of rudstone dolomite,biohermal dolomite,bioclastic dolomite and crystal dolomite,with residual intragranular dissolved pores,intercrystalline dissolved pores（dissolved cavities）as the main storage space,an average porosity of 2.85%.Structural fractures were well developed.The reef-shoal dolomite fracture-dissolution-porous reservoirs are main reservoir types of the D_2g.The formation of the reservoirs is controlled by reef-shoal facies,dolomitization and dissolution.Reefshoal facies provided the geological background of the reservoirs development.Dolomitization was the necessary condition of the reservoirs development.Dissolution was the key factor of the reservoirs development,and tectonics promote the final formation of the reservoirs.The reservoirs have experienced three evolution stages,sedimentation,dolomitization and dissolution laid the foundation for storage space types of the reservoirs.Tectonics improved the physical properties of the reservoirs,while the filling of asphaltic decreased the physical properties of the reservoirs.Based on the main controlling factors of Guanwushan reservoirs,dolomitized reef-shoal on the high geomorphology area among Jiange,Jiangyou and Mianyang area is predicted as the most favorable reservoir zone where will possibly haveexploration breakthroughs.

关 键 词：储集层特征 储集层演化 控制因素 中泥盆统 观雾山组 川西北地区 

分 类 号：TE122.2[石油与天然气工程—油气勘探]