摘要
为了研究中国东北地区东部盆地群下白垩统烃源岩的特征与页岩气勘探潜力,对三江盆地、鸡西盆地、通化盆地、柳河盆地和红庙子盆地进行了野外样品采集、烃源岩地球化学与岩矿测试,同时统计了其他盆地烃源岩的地球化学参数。结果表明,东部盆地群下白垩统的烃源岩有机质丰度和类型主要受沉积相的控制,有机质成熟度受莫霍面埋深的影响。下白垩统沉积时研究区北部水体较浅,泥岩累积厚度大、粉砂质含量高,有机质丰度达到了差一中的标准,干酪根主要为Ⅱ2-Ⅲ型,目前处于成熟-高熟阶段。研究区南部水体相对较深,泥岩平均累计厚度为233—446m,但泥岩质纯,有机质丰度较高,主要发育Ⅰ一Ⅱ2型干酪根,目前处于低熟-成熟阶段。东部盆地群下白垩统烃源岩脆性矿物含量较高,脆性较大,主要发育粘土矿物间孔缝、粒内孔和有机孔,具有微孔一中孔的孔喉结构,常规油气和页岩气勘探均具有良好的前景。
In order to study the characteristics of Lower Cretaceous source rocks and shale gas exploration potential of the eastern basin group in Northeast China, field sampling, geochemical analysis and rock-mineral tests of source rocks were performed and geochemical parameters were measured in the Sanjiang Basin,Jixi Basin, Tonghua Basin, Liuhe Basin and Hongmiaozi Basin. The results indicate that the abundance and type of organic matter in the Lower Cretaceous source rocks are mainly controlled by sedimentary facies,while the maturity of source rocks is influenced by the depth of Moho surface. The Lower Cretaceous source rocks in the north of the study area were deposited in shallow water environment that results in large cumulative thickness of mudstones and higher silt content. These source rocks contain type I12 ke- rogen and m kerogen and are graded as poor-moderate source rocks at mature to over-mature stages. The Lower Cretaceous source rocks in the south of the study area were deposited in deeper water environment that results in thick mudstone depo- sition (with thickness of 233 m to 446 m) and high organic content. These source rocks mainly contain type I - 1[2 kerogen at low-mature to mature stages. Moreover ,the Lower Cretaceous hydrocarbon source rocks are characterized by high content of brittle minerals,important content for development of pores and fractures between clay minerals, intergranular pores as well as organic pores with pore throat structure of micro- and meso- pore. Therefore,there exists favorable exploration pros- pects for both conventional hydrocarbon and shale gas in Lower Cretaceous of eastern basin group in Northeast China.
出处
《石油与天然气地质》
EI
CAS
CSCD
北大核心
2016年第6期893-902,共10页
Oil & Gas Geology
基金
国家自然科学基金项目(U1262106
41572135)
国家科技重大专项(2016ZX05046-001-006)
国土资源部中国地质调查局项目(12120115001701)
关键词
莫霍面
有机孔
烃源岩
页岩气
下白垩统
东部盆地群
Moho surface, organic pore, source rock, shale gas, Lower Cretaceous, eastern basin group