【作者】 李珊；

【导师】 孙卫；

【作者基本信息】 西北大学 ， 矿物学、岩石学、矿床学， 2014， 硕士

【摘要】 近年来姬塬地区的勘探工作成绩骄人,2013年以逾亿吨的储量跃居我国新增探明储量首位,但姬塬油田整体上地质条件复杂,长6段储层物性差,孔渗平面变化快,成岩作用强烈、孔喉类型多样、流体赋存空间构架特征多变,宏观和微观上各向非均质性显著等诸多不利因素导致其储层评价难度较大,未能建立合理成熟的储层评价标准,同时产能影响因素复杂,单井产能偏低,邻井间产量相差较大,开发效果不甚理想。本文针对上述问题,借助多种实验测试手段,综合利用多种分析资料,从小层划分、沉积微相、砂体特征入手,对储层岩石学及成岩作用、孔喉结构及渗流特征、非均质性等特征进行全面分析,合理优选主要参数进行储层综合分级评价,而后运用动态数据对单井产能进行定量预测,综合储层评价成果与产能预测结果最终划分出有利区带,主要成果如下：(1)本区构造稳定,发育北西、北东向交汇物源控制的湖泊三角洲前缘亚相水下分流河道和水下分流间湾等微相,从长63、长62到长61砂体规模和面积逐层扩大,纵向上砂体累积厚度逐层加厚。(2)本区长6储层属于典型的低孔低渗储层。从长63、长62到长61小层物性逐层变好。沉积期砂体频繁迁移叠覆,平面上物性变化块,区内隔层发育,单砂体数量多而厚度小,层内层理发育,渗透率纵向分异性强,孔喉空间配置关系复杂,非均质性强。(3)本区以细粒、极细粒长石砂岩为主,成分成熟度和结构成熟度中等,从长63到长61填隙物含量呈增多趋势,成岩作用强烈,压实和胶结作用大幅破坏孔隙,但局部交代和大面积的溶蚀改善储层物性,主要孔隙组合类型为溶孔-粒问孔和粒间孔-溶孔,喉道主要为片状、弯片状,孔喉多为大-中孔细喉或微细喉道组合类型。(4)将本区长6储层分为四类,一类储层以细粒砂岩为主,砂层厚度大,物性及含油性好,孔隙空间大,以相对粗喉道为主,储集和渗流能力好,平面上分布范围最小。二、三类储层以极细粒砂岩为主,总体孔渗性较好,中等-强非均质性,范围大。四类储层孔渗及含油性均差,中等-强非均质性,是研究区最差的储层类型。(5)研究区单井产能受多因素影响,灰色关联分析显示孔隙度、渗透率、有效厚度和含油饱和度、声波时差、电阻率等对产能影响程度较大。据单井产能预测结果和储层综合评价结果圈定Ⅰ类有利区面积62.37km2,Ⅱ类有利区面积449.69km2。更多还原

【Abstract】 In recent years, the achievement of exploration work in Jiyuan area is outstanding. Its newly incremental proved reserves of2013, with more than one hundred million tons of reserves, ranked the first in our country. The geological condition of Jiyuan oilfield is very complex, many negative factors, such as poor reservoir property, property plane changing quickly, intense diagenesis, various types of pore throat, fluid space frame features variable as well as strong heterogeneity affect its production. All above factors result in lower single well productive capacity, large production difference between adjacent well and unsatisfactory exploitation effect. For purpose of solving above problems, this article regards the reservoir comprehensive evaluation as the research content. By virtue of multiple experimental testing method and various data analysis, we conduct a comprehensive analysis of reservoir lithology, pore throat structure, percolation characteristic and reservoir heterogeneity from small layers division, classification of microfacies and research of the sandbodies distribution. Next, select reasonable main parameters to conduct comprehensive reservoir evaluation, and then using the test data to predict the single well production capacity, finally divide the favorable reservoir zones by comprehensive analysis of reservoir evaluation results and productivity prediction results. The results are as follows:(1) The tectonic and sedimentary environment in the study area is stable, and the development of the underwater distributary channel and underwater interdistributary bay microfacies of lacustrine delta front is control by the provenance from northwest and northeast. From Chang63to Chang61, the scale and size of the sand body on the plane is expanding step by step as well as the thickness on the vertical is thickening.(2) The Chang6reservoir in this area belongs to the typical low porosity and low permeability reservoir, the reservoir property becomes better from Chang63to Chang61.Reservoir characteristics are as follows:frequent migration and multi-period overlaid of depositional sandbodies, property changing quickly on the plane, developing intercalation between layers, containing many small thickness single sand body, beddings develop within the layer, vertical permeability anisotropy is strong, the spatial configuration of pore throat is complex, reservoir heterogeneity is strong. (3) The reservoir is mainly composed of fine-grained and very fine arkose, which are characterized by medium composition maturity and textural maturity. The quantity of interstitial material shows an increasing trend from Chang63to Chang61. The diagenesis is strong, and the compaction and cementation greatly destroy the pore, but local metasomatism and large areas of dissolution improve reservoir property. The main types of pore are dissolved pore and intergranular pore, throat types are mainly plates and curved sheet throat, pore and throat combination types are mainly fine pore throat and micro pore throat.(4) The Chang6reservoir in the study area can be divided into four categories. The first class reservoir is mainly the fine sandstone which is characterized by thick single sand, good properties and oil potential, large pore space, relatively coarse throats, good reserve capacity and permeability, but minimal in distribution range compared with other types. The second and third class reservoir are composed of very fine-grained sandstone, with overall good reservoir property, moderate-strong heterogeneity and wide distribution. The fourth class reservoir is the worst reservoir in the study area, which is poor in properties and oil potential and moderate-strong in heterogeneity.(5) The single well production capacity in the study area were affected by many factors, grey correlation analysis showed that porosity, permeability, effective thickness, oil saturation, acoustic transit time as well as electrical resistance have greater degree of influence on productive capacity. According to well productivity prediction results and the reservoir comprehensive evaluation results, I kind favorable area were select about62.37square kilometers, Ⅱ kind favorable area were sum to449.69square kilometers.更多还原