渭河盆地地热井伴生气地球化学特征及生物气资源量评价

发布时间：2018-05-18 12:53

  本文选题：渭河盆地 + 烃源岩评价　； 参考：《长安大学》2015年硕士论文

【摘要】：渭河盆地是西南部的特提斯板块系统、东南部环太平洋板块系统和北部的欧亚板块系统相辐合地带,位于鄂尔多斯盆地南缘与秦岭造山带之间的一个新生代断陷盆地。渭河盆地赋存多种具有工业价值的资源,如地热水、生物气、氦气和金属矿产等,是一个非常极具资源开发潜力和重大工业价值的沉积盆地。本文在分析前人研究成果和盆地基础地质资料的基础上,通过对渭河盆地的基础地质和盆地构造演化史的分析,地层划分与对比、沉积相与砂体展布、储层分析与研究、资源分布规律研究等综合研究,对烃源岩进行评价,天然气样品的成分、成因进行了系统的综合分析和研究。地化特征表明,张家坡组烃源岩有机质丰度较高,达到差-中级别;有机质类型主要为含腐殖腐泥型(Ⅱ1)和腐泥型(I)为主,类型较好;当烃源岩埋深达到1845米时,Ro=0.597%,仍处于低成熟度阶段,为成熟早期。烃源岩评价结果表明,渭河盆地有着良好的生油气潜力。渭河盆地水溶氦气以壳源氦为主,并有少量幔源氦加入。氦气源岩主要为盆地基底与周缘的花岗岩,有高含量的铀、钍及强放射性活度特征。氦气以断裂、低渗岩层和高渗砂岩层为运移通道,运移到储集层成藏。高陵群组及蓝田灞河组与上覆张家坡组形成的异常压力封闭,有利于盆地内富氦水溶气的富集和保存。渭河盆地伴生气存在四种天然气类型,其中以生物气,生物-热催化过渡带气为主同时含有少量的无机气和热解气。生物气母质来源同腐泥型和腐殖型有机质有关,热解气具有煤成气的特征。渭南地区与咸阳地区伴生气气源岩年龄为下奥陶-寒武纪;西安地区伴生气气源岩年龄为奥陶纪。与渭河盆地固市凹陷具有同柴达木三湖地区生物气相似的资源条件,通过计算生气量发现,固市凹陷张家坡组具有大型生物气成藏的地质条件。
[Abstract]:The Weihe basin is a Cenozoic faulted basin located between the southern margin of Ordos basin and the Qinling orogenic belt, which is a convergence zone between the Tethys plate system in the southwest, the Pacific plate system in the southeast and the Eurasian plate system in the north. There are many kinds of resources of industrial value in Weihe Basin, such as geothermal water, biogas, helium gas and metal minerals, etc. It is a sedimentary basin with great potential for resource development and great industrial value. Based on the analysis of previous research results and basic geological data of the basin, this paper analyzes the history of basic geology and structural evolution of the Weihe basin, stratigraphic division and correlation, sedimentary facies and sandbody distribution, reservoir analysis and study. Based on the comprehensive study of resource distribution law, the evaluation of hydrocarbon source rock, the composition and origin of natural gas samples are systematically analyzed and studied. The geochemical characteristics show that the organic matter abundance of the source rocks of Zhangjiapo formation is relatively high, and the organic matter types are mainly humic saprophytic mud type (鈪，

本文编号：1905908