银川盆地页岩气形成件分析.docxVIP

银川盆地页岩气形成条件分析摘要：银川盆地南起青铜峡，北至石嘴山，西依贺兰山， 东靠鄂尔多斯盆地西缘，南北长165km，东西宽42~60km，总面积7790km2，银川盆地在地质构造上被称为“银川地堑”。银川盆地整体呈北北东走向，基底呈南北高、中部低的船形，盆地中心位于平罗、贺兰、银川、永宁一带，最深部位大体位于平罗-银川一线以西及永宁、灵武之间的断陷处，在纵剖面上由平罗往北和由永宁向南又呈断阶状抬升。整个盆地为一东缓西陡的“向斜盆地”。为研究银川盆地页岩气形成条件，通过查阅相关文献以及对平凉组岩矿特征，含气页岩分布，页岩气有机地球化学的研究，对其地化特征做出初步评价：银川盆地3 口参数井仅银参1井曾采样进行生油分析。2036.5～3358.9 m 井段累积暗色泥质岩厚度为515.9m。其中，清水营组暗色泥岩层厚度为290.4 m，有利生油层段为3204～328l m， 泥岩单层厚度约为5m， 最大单层厚度达20.5 m，并含有黄铁矿颗粒；有机碳含量TOC为0.47%～0.5%，氯仿沥青“A”含量为0.0797%，有机质丰度一般；干酪根组分中类脂组分含量为64.71%～72.24 %，生油岩属Ⅱ型；镜质组反射率Ro为0.69%，全烃色谱资料计算OEP为1.18，说明该段有机质已经进入成熟阶段。灵武坳陷、银川北凹陷、常信凹陷和平罗凹陷都处在有利的生烃范围。初步推测，清水营组成熟生油岩面积大于200km2。但是对古近系的清水营组中、下部的沉积环境、岩性以及生烃能力的认识还不清楚。目前，要解决这些问题则需要利用现有的资料寻找隐含着的地质信息，进行合理的推测，页岩气的勘探前景也未知。关键词：银川盆地；页岩气；鄂尔多斯盆地；向斜盆地；地化特征Conditions For Occurrence Of Shale Gas In Yinchuan BasinAbstract: South of Yinchuan Basin since Qingtongxia,north to Shizuishan,Helan Mountain in the west,East on the western margin of the Ordos Basin,165km long from north to south,east-west width of 42~60km. With a total area of 7790km2 and Yinchuan Basin in geological structure is said to Yinchuan graben. Yinchuan basin is a NNE strike,the basement was North South high and low in the middle of the boat shaped,basin,located in the center of the Pingluo,Helan,Yinchuan,Yongning area,the deepest gross area is located in between the Pingluo - Yinchuan line west and Yongning,Lingwu fault depression at,in longitudinal section by Pingluo to the north and You Yongning South and was broken order form uplift. The whole basin is a steep slope in the west synclinal basin. For the study of Yinchuan basin shale gas formation conditions,by consulting relevant literature and distribution of Pingliang Formation Characteristics of rocks and minerals,including shale gas,shale gas of organic geochemistry research,make a preliminary evaluation of its characteristics: Yinchuan basin 3 parameter wells only silver reference 1 well was sampled for source analysis. 2036.5 ~ 3358.9 m wells cumulative dark mudstone thickness is 5