作　　者： ; ; ; ; ; ;

机构地区： 中国科学院

出　　处： 《天然气工业》 2010年第2期40-44,共5页

摘　　要： 鸡西盆地煤田开发历史较长,但油气地质条件研究尚处在起步阶段,对盆地油气地质条件和勘探前景进行系统分析,对大庆外围战略选区具有重要的意义。对盆地内煤岩和暗色泥岩烃源岩的显微有机组分、有机地化指标进行实验室测试分析,结果显示:煤层壳质组含量很低,镜质组含量普遍大于70%,有机质演化均达到"低—中成熟"阶段;暗色泥岩有机碳含量很高,但烃类转化率较低,有机质演化已经达到成熟阶段;两者的有机质类型以腐殖型为主。据此认为盆地生油条件差但生气条件好。盆地煤层平均孔隙度为2.5%,砂岩孔隙为中—低孔低渗细喉道型,可以作为较好的天然气储层。实验数据显示凝灰岩的突破压力平均为243.4×105Pa,穆棱组泥岩的突破压力为900×105Pa,可以作为较好的盖层。依据煤田探采资料编制了盆地烃源岩等厚图,结合鸡西盆地沉积、构造特征分析认为:盆地有较好的天然气勘探潜力和生储盖组合条件,最易形成地层和岩性圈闭;北部坳陷的西鸡西—东海深部区间带和南部坳陷的穆棱矿—荣华区间为勘探的首选有利区带。 Research on petroleum geologic conditions of the Jixi Basin is still at the initial stage,although the history of coal field development is quite long in this basin.Systematic analysis of the petroleum geologic conditions and exploration potentials in the basin is of great significance to the selection of strategic exploration areas in the periphery of the Daqing oilfield.Laboratory tests of the micro-organic compounds and organic geochemical indicators of the coal rocks and dark mudstone source rocks reveal that the coal has low exinite content but generally high vitrinite content over 70% and their organic matters are low-to-middle in maturation.The dark mudstone is very high in organic carbon content but low in hydrocarbon conversion and its organic matters are mature.The kerogens of both the coal and the dark mudstone are dominated by type Ⅲ,indicating low oil generation potential but high gas generation potential.The coal layers have an average porosity of 2.5% and the pores of sandstone are of narrow throat type with middle-to-low porosity and low permeability,thus they can act as good gas reservoirs.Experimental data show that the breakthrough pressure of tuff averages at 243.4×105 Pa and that of the Muling Formation mudstone is 900×105 Pa,thus they can act as relatively good seals.The isopach of the source rocks in the basin is mapped based on the prospecting and production data of the coal fields.Analyses in combination with the sedimentary and structural features of the basin reveal that the gas exploration potential is large and source-reservoir-seal assemblages are favorable.Stratigraphic and lithologic traps are the most common trap types.Based on source,reservoir and seal conditions,it is believed that favorable plays occur in the northern depression and southern depression.

关 键 词： 鸡西盆地 早白垩世 煤层气 烃源岩 生储盖组合 圈闭 勘探方向

领　　域： [天文地球] [天文地球] [矿业工程]