摘要
渤海蓬莱9-1潜山油藏是以中生代花岗岩风化壳为储层的大型油藏。在花岗岩潜山这个新领域的勘探实践中,储层特征及成储化条件是困扰勘探的关键。通过薄片、岩心、测井、地震以及野外露头等资料综合分析了花岗岩储层特征与形成条件。研究表明,花岗岩风化壳上部主要为孔隙型储层,风化壳底部主要为裂缝型储层,平面上花岗岩风化壳储层主要分布在花岗岩体东侧。花岗岩大型节理发育、风化淋滤作用、构造改造、古地貌和浅埋藏是花岗岩规模化成储的重要条件,其中花岗岩大型节理发育是规模化成储的内在基础,风化淋滤作用和构造改造是规模化成储的主导因素,古地貌和浅埋藏是规模化储层得以保存的关键,构造改造与古地貌的耦合关系决定了储层发育程度,构造改造强烈且处于古地貌斜坡区的花岗岩体东侧是有利储层发育区,构造改造较弱并处于古地貌斜坡区的花岗岩体西侧储层发育次之,构造改造较弱且位于古地貌高点的花岗岩体轴部储层最不发育。该研究成果对于蓬莱9-1花岗岩油藏的后续开发及类似花岗岩潜山的勘探具有参考意义。
Penglai 9-1Oilfield is the large-scale weathering crust reservoir of Mesozoic granite buried hill in Bohai Gulf Basin.Reservoir characteristics and formation conditions play significant role in the new exploration field of granite buried hill.Reservoir features and controlling factors were studied by the comprehensive analysis of thin section identification under the microscope,drilling cores,logging data,seismic data,and field outcrops.The results show that Penglai 9-1granite reservoir could be divided into mud zone,sand-conglomerate zone,fracture zone and base rock zone from surface to interior due to the control of weathering leaching process,and the reservoir space is changed vertically with laws from pore,fracturepore to pore-fracture,and fracture.The reservoir developments of granite buried hill are mainly controlled by large-scale granite joint,weathering leaching process,structural deformation,palaeogeomorphology and shallow burial environments.The development degree of the reservoir is determined by the relationship between structural deformation and palaeogeomorphology.The most favorable reservoir zone is located where the structure deformed strongly and palaeogeomorphology is slope area on the eastern side of the granitic body and the next favorable zone is located where structure deformed weakly and palaeogeomorphology is slope area on the western side of granitic body.While the most unfavorable zone is located where structure deformed weakly and palaeogeomorphology is high position in the granite body axis.The large-scale development of granite joint is the inner base of large-scale reservoir formation,weathering leaching and the tectonic deformation is the dominant factor of large-scale reservoir formation,and the palaeogeomorphology and shallow burial environments are the key to large-scale reservoir preservation.The study results will be a significant reference in the subsequent development of Penglai 9-1granite Oilfield and the exploration of the similar granite buried hills.
引文
[1]杨明慧.渤海湾盆地潜山多样性及其成藏要素比较分析[J].石油与天然气地质,2008,29(5):623-631.
[2]罗静兰,侯连华,蒋宜勤.陆东地区火成岩形成时代与构造背景及火山岩储层成因[J].石油学报,2012,33(3):351-360.
[3]王京红,靳久强,朱如凯,等.新疆北部石炭系火山岩风化壳有效储层特征及分布规律[J].石油学报,2011,32(5):757-765.
[4]吴志斌.大民屯凹陷前进潜山带沈288区块太古宇潜山油藏特征[J].地质科技情报,2015,34(3):139-145.
[5]Cuong Trinhxuan,Warren J K.Bach Ho Field,A fractured granitic basement reservoir,CuuLong Basin,offshore Se Vietnam:A“Buried-Hill”play[J].Journal of Petroleum Geology,2009,32(2):129-156.
[6]Li Bingjian.The natural fracture evaluation in the unconventional tight oligocene reservoirs:Case studies from CuuLong Basin,southern offshore Vietnam[C]∥Society of Petroleum Engineers.SPE Asia Pacific Oil and Gas Conference and Exhibition 2011.2011(2):955-965.
[7]Borgohain T.Reservoir fairway analysis of a Barail interval of Deohal area in upper Assam Basin using high resolution sequence stratigraphy and seismic attributes[C]∥Anon.Annual AAPG Convention.[S.l.]:[s.n.],2010.
[8]Haskell J B,Toelsie S,Mohan A.Optimization of sand control for unconsolidated,shallow,and low-pressure sandstone reservoirs:A Suriname case study[C]∥Society of Petroleum Engineers.Trinidad and Tobago Energy Resources Conference2010,2010:953-964.
[9]周坤,杨志冬,范存辉,等.准噶尔西北缘四_2区火山岩风化壳储层裂缝特征[J].地质科技情报,2015,34(1):28-34.
[10]贾振远,蔡忠贤.碳酸盐岩古风化壳储集层(体)研究[J].地质科技情报,2004,23(4):94-104.
[11]王昕,周心怀,徐国胜,等.渤海海域蓬莱9-1花岗岩潜山大型油气田储层发育特征与主控因素[J].石油与天然气地质,2015,36(2):262-270.
[12]Ruxton B P,Berry L.Weathering of granite and associated erosional feratures in Hong Kong[J].Bulletin of The Geological Society of America,1967,68,1283-1292.
[13]高山林,李学万,宋柏荣.辽河盆地欧利坨子地区火山岩储集空间特征[J].石油与天然气地质,2001,22(2):174-177.
[14]朱世发,朱筱敏,吴冬,等.准噶尔盆地西北缘下二叠统油气储层中火山物质蚀变及控制因素[J].石油与天然气地质,2014,35(1):77-86.
[15]窦顺梅,陈繁荣,杨永强,等.花岗岩地区水-岩反应次生矿物的沉淀饱和指数估算[J].地球化学,2010,39(4):326-336.
[16]Dewande B,Lachassagne P,Wyns R,et al.A generalized 3-D geological and hydrogeological conceptual mode of granite aquifers controlled by single or multiphase weathering[J].Journal of Hydrology,2006,330:260-284.
[17]黄镇国.中国南方红色风化壳[M].北京:海洋出版社,1996.
[18]杨洁.华南沿海花岗岩风化壳岩土工程特征变化研究[D].西安:西安科技大学,2004.
[19]余一欣,周心怀,徐长贵,等.渤海海域新生代断裂发育特征及形成机制[J].石油与天然气地质,2011,32(2):273-280.
[20]周心怀,牛成民,滕长宇.环渤中地区新构造运动期断裂活动与油气成藏关系[J].石油与天然气地质,2009,30(4):469-475.
[21]韦阿娟.渤海海域中生界火成岩岩性测井识别技术及应用[J].地质科技情报,2015,34(6):207-213.