雅布赖盆地侏罗系烃源岩特征及油气勘探方向  

Characteristics of Jurassic Source Rocks and Direction of Petroleum Exploration in Yabulai Basin,China

作　　者：黄军平[1] 杨克荣 杨占龙[1] 王斌婷[1] 向倪娇[1] 邓毅林[1] 韩小峰[1] 

机构地区：[1]中国石油勘探开发研究院西北分院,甘肃兰州730020 [2]中国石油玉门油田分公司勘探开发研究院,甘肃酒泉735019

出　　处：《天然气地球科学》2013年第5期948-955,共8页Natural Gas Geoscience

摘　　要：雅布赖盆地侏罗系具有油气资源潜力，但勘探程度较低。为给勘探部署提供参考信息，主要通过分析侏罗系的烃源岩地球化学特征，结合地层分布和地质背景，研究了生烃潜力，并进一步讨论了油气勘探方向。中侏罗统新河组下段湖相泥岩是研究区的主力烃源岩，中侏罗统青土井组次之，相比而言，上侏罗统沙枣河组为非差烃源岩。新河组下段烃源岩厚度大，约为35～1174m，有机质丰度较高，有机碳含量均值为1．61％。有机质类型以Ⅱ型为主，多数有机质热演化程度处于成熟阶段。小湖次凹烃源岩干酪根显微组分中发现藻纹层和泥岩互层分布的有机质高度富集段，进一步表明新河组下段具有良好的生烃潜力。平面上，新河组下段生烃潜力以小湖子次凹和盐场次凹好于梭托次凹为特征，这主要是由于小湖子次凹和盐场次凹烃源岩埋藏深、地温梯度较梭托次凹高，而梭托次凹烃源岩埋藏浅，热演化程度较低所致。盆地南部构造高部位或洼槽区岩性圈闭发育部位为近期勘探值得考虑并关注的方向。这些认识还可供西北其他地区侏罗系烃源岩研究作类比参考。The Jurassic offers a good exploration objective in the Yabulai Basin which is poorly explored. Based on the geochemical study of the Jurassic potential source rocks,it can be concluded that mudstone of the Lower Xinhe Formation in the Middle Jurassic is the main source rock which deposited in the lacustrine facies,the Qingtujing Formation is moderate source rock,and Shazaohe Formation is the poorest source rock. Results show that the Lower Xinhe Formation source rock has large thickness, ranging from 35 to 1 174re,and it contains high TOC with an average of 1.61%. It is dominated by type Ⅱ organic matter which is at mature stage. In addition, a lot of interbedded lamalginite and mudstone are present in the source rock from Xiaohuzi sub-depression, indicating that the Lower Xinhe Formation source rock has a good hydrocarbon potential. In the plane, the hydrocarbon potential of the Lower Xinhe Formation source rock in Xiaohuzi and Yanchang Sags is better than that in Suotuo Sag. The main reasons are that source rock in the Suotuo Sag was shallowly buried and at the stage of low mature period. The structure high points of the southern basin or the lithologic trap developed locations in deep depression are the main tar- gets for the latest petroleum exploration. The analysis above can also be used for analogical study of the Ju- rassic source rocks in the other parts of the northwest China.

关 键 词：侏罗系 烃源岩 生烃潜力 雅布赖盆地 

分 类 号：TE122.112[石油与天然气工程—油气勘探]