【作者】 梁春秀；

【导师】 施泽进；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2003， 博士

【摘要】 面临增储上产，稳产高产的巨大压力，随着勘探难度的加大，寻找隐蔽性非常规油气藏业已成为油气勘探开发领域的重中之重，低电阻率油藏就是其中的重要目标之一。随着勘探步伐的加快，深入认识及定量评价低阻油层已十分必要。针对含油气盆地中的这一具有重要理论意义和实践价值的研究对象，本文以松辽盆地南部作为窗口，在广泛调研了松辽盆地南部关于低阻储层大量的基础资料的基础上，选择了有代表性的六个地区（大老爷府、大情字井、海坨子、四方坨子、红岗及大安北），对这些地区的测井综合解释图、岩心综合图、物性分析报告、试油地质报告、储量报告、相关研究报告等资料进行了消化吸收。精选了大老爷府、大情字井、海坨子和四方坨子地区共四个地区五个低阻层位(大老爷府（K_lq_n¹）、大情字井(k_ly¹、K_lqn²⁺³)、海坨子(K_ly²⁺³)、四方坨子（K_lq_n³）)的19口井60余块岩心进行分析测试，阐明了低阻储层形成的地质背景；分析对比了常规与低阻储层的岩性组成、物性、电性、微观孔隙结构及流体特征；从而剖析了松辽盆地南部低阻油层的形成机理。通过对岩心的化验分析、测试及岩石物理实验结果的分析、利用核磁等新资料，建立了针对低阻储层参数的高精度定量测井解释模型；砂泥岩薄互层条件下的实用电性校正图版；与毛管压力分析资料相结合，在该区首次建立了基于T_2CUTOFF未知条件下的储层参数评价模型，成功地避免了因实际的T₂截止值波动而引起的解释误差大的问题。建立了多种半定量、定量识别低阻油水层的方法，使解释符合率明显提高，达到了预期的目的，成效显著。主要成果和认识包括以下12个方面： 1、从研究区业已发现的低阻油层来看，松辽盆地南部研究区低阻油层均为相对低阻油层。因此，将电阻增大率（油层电阻率与相似物性条件下的水层电阻率之比）≤3的油层定义为低阻油层。 2、松辽盆地南部低阻储层发育区均位于扇三角洲（或三角洲）前缘亚相中的河口坝、远砂坝、席状砂等沉积微相中，这些扇三角洲（或三角洲）前缘亚相的岩性构成均以细粒的粉砂岩、泥质粉砂岩以及粉砂质泥岩为主，并含有较高的泥质成分，这种岩性组合特征和其潜在的孔隙微观结构特征、孔隙流体特征为这些区域中低阻油层的形成提供了必要的地质背景。 3、低阻储层的岩性主要是粉砂岩，泥质含量较高；岩石骨架矿物成分成熟度较低，主要有石英、长石和岩屑，其中以长石为主、石英次之；胶结物以灰质和泥质为主:所含粘土的矿物成份以伊利石、伊/蒙混层为主;碳酸盐含量一般较少，部分含量较高;黄铁矿含量较低，大多含量小于4%。 4、研究区低阻储层孔隙结构较复杂，表现为双峰特征，非均质程度较高，孔隙的最大连通孔喉半径普遍较小，而且变化区间很大。 5、四方蛇子、大情字井、海沱子及大老爷府油田低阻储层普遍为中孔一低孔、低渗一特低渗储集层，孔隙度一般为10%一20%，渗透率一般在小于1 x 10一3pmZ一 100X10一3pm，之间，束缚水饱和度一般为17%一35%。大老爷府青一段束缚水饱和度较高，普遍在35%一60%之间，高含量的束缚水饱和度正是大老爷府青一段高台子油层明显低阻特性的重要原因之一。 6、研究区低阻层地层水总矿化度一般在2500m幼一27000m叨之间，主要位于100oom幼一2仪x刃m幼。地层水的离子成分为:阳离子K+、Na十、Mg十+、Ca++;阴离子CI一、50万、HCO二。主要以K十、 Na+、CI一、HCO互为主。地层水水型主要是NaHCO。水型。在电性上属于低矿化度水型。低阻储层的岩石绝大多数具有亲水性。 7、受成岩作用的影响，浅部储层粘土矿物的附加导电性较强，而深部储层 （特别是埋深大于2000米地层）粘土矿物的附加导电性将变得很弱。 8、低电阻率储层的形成机理有其共同原因:（l）均形成于三角洲（或扇三角洲）前缘的河口坝、远砂坝、席状砂等沉积微相中;（2）岩石颗粒细（粒度中值一般<0 .07Inln），泥质成分多（泥质含量普遍>5%），岩性组合为粉砂岩、泥质粉砂岩、粉砂质泥岩，岩石孔隙结构较复杂;（3）粘土矿物含量较高，粘土矿物中高含伊/蒙混层、伊利石等矿物（相对含量一般>70%）;（4）储层束缚水含量高（普遍>20%）。还存在特殊原因:（1）储层微孔隙、次生孔隙发育，具粒间孔一裂缝双重孔隙系统或裂缝系统;（2）油藏为低幅度构造，油藏高度小，油水过渡带宽，油层含水饱和度高;（3）地层水矿化度较高（或较低）;（4）测井原因（如方44、方54）;（5）岩石中局部含有导电性能良好的金属矿物。 9、研究区低阻储层参数的定量解释模型包括:地层孔隙度模型、渗透率模型、饱和度解释模型、束缚水饱和度解释模型、储层参数优化解释模型。应用核磁新资料解释储层参数特别是束缚水饱和度比应用常规资料具有更高的精度。 10、实用的薄层校正图版可以有效校正砂泥岩互层条件下的地层电阻率。 11、测井新方法应用于低阻储层评价效果良好。利用核磁共振测井资料，建立的基于TZc二，}已知条件下的储层参数评价模型;与毛管压力分析资料相结合，建立的基于TZc。。F。未知条件下的储层参数评价模型，成功地避免了因实际的T:截止值波动而引起的解释误差大的问题。更多还原

【Abstract】 With increasing of the exploration difficulty, it is important to seek the subtle and unconventional pool in the petroleum exploration and development fields, the low resistivity pool is one of the most important targets. It is very necessary to deeply realize and quantitatively evaluate the low resistivity oil bed with expediting of the exploration step. This study object has important theoretical significance and practical value in the petroliferous basin. In this paper, based on the widely studying the basic data on low resistivity reservoir bed, the author selects six representative regions (Dalaoyefu, Daqingzijing, Haituozi, Sifangtuozi, Hongang and Daanbei) and assimilates many data, such as well logging integrated interpretation figure ,core comprehensive map, analysis report of physical properties, production test of geology report, reserves report and so on., then selects five low resistivity beds (Dalaoyefu (K1qn1) , Daqingzijing (K1y1, K1q2+3), Haituozi (K1y2+3), Sifangtuozi (K1qn3)) in Dalaoyefu, Daqingzijing, Haituozi and Sifangtuozi regions and tests more 60 blocks of core samples, illuminates the geologic background on formation of the low resistivity reserve, analyzes and correlates lithology composition, physical properties, electrical property, microscopic pore structure and hydro-character between normal and low resistivity reservoir bed. Based on these studies, this paper anatomizes the formation mechanism of low resistivity reservoir bed. From assay of core, researching the result of the petrophysical test and utilizing the NMR data, builds the high precision and quantification logging interpretation model and the practical electrical property correction chart in the condition of sandstone and mudstone thin interbed. Combines the capillary analysis data, firstly builds the reservoir bed parameter interpretation model under the condition of unknown T2cutofb successfully decreases the interpretation error derived from T2 cutoff fluctuating. This paper designs semi-quantitative and quantitative methods, which can identify low resistivity oil-bed and water-bed. The main achievement and realization as follows:1. The low resistivity oil bed is relatively low resistivity oil bed in the southern Songliao basin, so the oil-bearing formation whose resistivity increase rate resistivity of oil bed vs resistivity of water-bed under the condition of similar physical properties less than or equal to 3 is defined as the low resistivity oil bed.2. The low resistivity reservoir bed is located in the sedimentary microfacies of the fan delta frontal (or delta) subfacies, such as river mouth bar, distal bar, sheet sand and so on, whose lithology compositions is fine aleurolite, pelitic siltstone and silty mudstone. This lithology composition character and the potential microscopic pore structure character, hydro-character in the pore consist of are necessary geologic background during the formation of the low resistivity reservoir.3. The main lithology of low resistivity reservoir is siltstone, the pelitic content is higher, the mineral component maturity of rock skeleton is lower, which includes quartz, feldspar and detritus, the feldspar content is higher than that of quartz. The cementing matter is calcic and pelitic; the clay mineral component is main illite and illite/smectite mixed layer. In general the carbonate content is low in reservoir, but some parts are high, the pyrite content is low (<4%).4. The low resistivity reservoir pore structure is complex and distributes double peak character, the heterogeneity degree is strong, the maximum effective pore and throat radius is small and the variation interval is big.5. The conducive reservoir belongs to range from middle porosity to low porosity and from low permeability to especial low permeability, the porosity variation range is from 10 percent to 20 percent and the permeability is less than 1-100X 10-3u m2, at the same time, the bound water saturation variation range is from 17 percent to 35 percent. High bound water saturation i更多还原