苏西致密砂岩气藏储层产水机理及预测

发布时间：2018-04-13 00:27

本文选题：苏里格西区 + 可动水饱和度　；参考：《中国科学院研究生院(渗流流体力学研究所)》2015年硕士论文

【摘要】：随着全球经济的快速发展,油气的消耗速度也在不断的增加。因而,作为中国目前已发现的最大的天然气气田-位于鄂尔多斯盆地北部的苏里格气田受到越来越多的关注。苏里格气田储层为低渗致密含水储层,其主力储层的开发效果较差,本文在前人苏里格西部区块研究成果的基础上,结合矿场生产资料、测井解释数据,对苏西地区产水规律、主要产水层位的判断以及射孔层位的选择进行综合研究,取得了如下成果与认识：(1)应用核磁共振测试技术测量分析苏里格气藏多块岩样的孔隙结构特征,统计所有苏里格气藏岩样的核磁共振测试结果表明：苏里格气藏致密储层主要发育小孔、中孔和微孔,大孔隙不发育。经过多次实验研究,明确300psi的离心力最接近于致密砂岩气藏成藏过程中的排驱压力,因此在300psi离心条件下的含水饱和度值可以近似认为是苏里格气藏的储层原始饱和度值。选取苏里格致密储层具有代表性的岩样在300psi离心力离心后的核磁共振测试结果显示：气藏致密储层大孔喉少,主要发育微细孔喉,饱和岩样在300psi离心力下仅能离心出少量水相,表明微细孔喉对液相控制作用强。(2)总结了气井产水对产能的影响。通过对比苏里格气藏西北部三个气站的见水前后的产能,可以看出,已见水气井见水前产能较未见水气井产能低,见水后产能快速递减(年递减率60%,全区20%),只有见水前的1/3～1/4,气井产水对单井产能影响大。对比气井当前累计产气量和最终累计产气量,可以看出：气井一旦见水,后续产气能力弱,最终累产气量小于经济极限产气量(1400×104m3),最终累计产气量只有未见水井累产气量的20%～30%。(3)利用核磁共振技术测得岩心的束缚水饱和度,再结合室内实验测得的岩心孔隙度值,拟合计算出束缚水饱和度与孔隙度的关系曲线,结合测井解释数据计算出各个深度点的可动水饱和度,并绘制出可动水饱和度的纵向分布曲线。通过分析大量的可动水饱和度的常规测井解释结果与实际生产数据,明确了储层的可动水饱和度越大,对应气井的产水量越大这一特点,并且明确了气井是否产水的可动水饱和度临界值为10%：建立了气井的产水特征预测方法。(4)利用上述方法对已开发井的产水层位进行预测,并指导射孔层位的选择。在选择射孔层位时,应当综合考虑可动水饱和度、含气饱和度、孔渗特征等影响因素,并根据可动水饱和度测井解释数据,优先射开可动水饱和度小于10%、含气饱和度大于50%的储层,以提高气层的产气能力,有效降低气井的产水风险。(5)在此基础之上绘制了苏里格致密砂岩气藏研究区块的可动水饱和度平面分布图,进而优选出低产水风险区,明确该区块的主力储层为盒8段和山1段。
[Abstract]:With the rapid development of the global economy, oil and gas consumption rate is also increasing.As a result, Sulige gas field, the largest gas field in China, located in the north of Ordos Basin, has attracted more and more attention.Sulige gas field reservoir is low permeability tight water cut reservoir, and its main reservoir's development effect is poor. Based on the research results of the western block of Sulige, combining with the field production data and logging interpretation data, this paper gives the water production law to the west of Jiangsu province.The judgment of the main water-producing layer and the selection of perforation layer are studied synthetically, and the following results and understandings are obtained. (1) the pore structure characteristics of many rock samples in Sulige gas reservoir are measured and analyzed by nuclear magnetic resonance (NMR) test technique.The results of nuclear magnetic resonance (NMR) measurements of all the samples of sullige gas reservoir show that the tight reservoir of Sulige gas reservoir mainly develops micropores, mesoporous and micropores, and the macropores are not developed.After many experiments, it is concluded that the centrifugal force of 300psi is the closest to the displacement pressure in the formation of tight sandstone gas reservoir, so the water saturation value under 300psi centrifugal condition can be approximately considered as the original saturation value of Sulige gas reservoir.The nuclear magnetic resonance (NMR) test results of the representative rock samples of Sulige tight reservoir after centrifugation by 300psi centrifugal force show that the gas reservoir has few large pore throats and mainly developed micro pore throats, and saturated rock samples can only centrifuge a small amount of water phase under the centrifugal force of 300psi.It shows that the micropore throat has a strong effect on liquid phase control. 2) the effect of gas well water production on productivity is summarized.By comparing the productivity of the three gas stations in the northwest of Sulige gas reservoir before and after water injection, it can be seen that the productivity of the gas wells that have already appeared is lower than that of the wells without water.The productivity decreases rapidly after water (annual decline rate is 60%, the whole area is 20%, only 1 / 3 / 1 / 4 of the water before water, gas well water production has a great impact on single well productivity.In contrast to the current cumulative gas production and the final cumulative gas production of gas wells, it can be seen that once the gas wells see water, the subsequent gas production capacity is weak.The final cumulative gas production is less than the economic limit gas production rate of 1400 脳 10 ~ 4 m ~ (3), and the final accumulative gas production is only 20% 30% of the cumulative gas production of no well.) the irreducible water saturation of the core is measured by nuclear magnetic resonance (NMR) technology, and the core porosity value measured by laboratory experiments is combined.The curve of relation between irreducible water saturation and porosity was calculated by fitting, and the movable water saturation at every depth point was calculated with log interpretation data, and the longitudinal distribution curve of movable water saturation was drawn.By analyzing a large number of conventional logging interpretation results and actual production data of movable water saturation, it is clear that the greater the movable water saturation of reservoir, the greater the water production of gas wells.It is determined that the critical value of movable water saturation of gas wells is 10: the prediction method of water production characteristics of gas wells is established. (4) using the above methods, the water producing zones of developed wells are predicted, and the selection of perforation layers is guided.In selecting the perforating layer, we should consider comprehensively the influence factors such as movable water saturation, gas saturation, porosity and permeability characteristics, and interpret the data according to the movable water saturation logging.In order to improve the gas production capacity of gas reservoir, the water saturation of movable water is less than 10, and the saturation of gas is more than 50%.On the basis of effectively reducing the water production risk of gas wells, the plane distribution map of movable water saturation of Sulige tight sandstone gas reservoir research block is drawn, and the low water production risk area is selected.It is clear that the main reservoirs in this block are Box 8 and Shan 1.
【学位授予单位】：中国科学院研究生院(渗流流体力学研究所)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE31

【参考文献】