鄂尔多斯盆地西部油区延长组致密油储层裂缝测井评价

鄂尔多斯盆地西部上三叠统延长组致密油储层中发育大量裂缝。但是,目前缺少针对强非均质性陆相致密油储层裂缝的测井识别方法的系统研究。以西部油区延长组长6~长8地层为例,利用大量取心、常规及微电阻率成像测井资料,对致密油储层裂缝的测井评价方法进行了系统研究。研究结果表明,长6~长8地层致密砂岩中主要发育高角度及垂直构造剪切缝、张裂缝及层理缝。裂缝密度主要分布在0~0.2条/m,低幅度构造区裂缝发育程度相对较低。在构建常规测井裂缝模型过程中,首先对测井曲线进行预处理,并消除了泥质及凝灰质的不利影响。然后,在对各单一常规测井曲线的裂缝敏感性分析基础上,依次构建基于曲线变化率的裂缝表征参数模型、基于曲线分形维数的裂缝表征参数模型、基于微电极幅度差的裂缝表征参数模型及综合指数模型。综合指数模型实现了多常规测井信息融合及逐步剔除功能,能有效识别砂岩中的裂缝发育段,裂缝识别精度可达80%。根据裂缝方位分析确定了裂缝的形成与区域应力环境的耦合关系,砂体厚度与裂缝的发育程度具有一定负相关性。但对部分砂体而言,裂缝发育程度与单砂体厚度具有一定正相关关系,反映出这类砂岩可能位于应力相对集中的特殊构造部位。该研究可以为致密油甜点预测提供科学指导。

南海西部油区低阻油层识别与定量评价

南海西部油区存在大量的低阻油层,常规测井难以对其进行有效的识别和评价。根据区域低阻油层的测井响应特征,并结合岩心资料对地层的宏观特征和微观孔隙结构进行了分析,指出导致油层低阻特征的主要地质原因是地层泥质和束缚水含量较高。利用烃源岩测井评价中常用的Δlg R技术和多矿物最优化方法,通过选取合适的矿物和流体组分,建立多矿物模型,得到多矿物剖面和储层参数,并结合核磁共振T2谱特征,及核磁孔径分布、核磁粘土水和束缚水饱和度等核磁处理成果,对低阻油层进行综合评价,并利用密闭岩心化验分析资料对测井解释成果进行了标定,重构测井曲线与实测曲线的吻合程度达到95%以上,可利用该方法对低阻油层进行有效识别和定量评价。

柴达木盆地西部油区特态矿物在油气勘探中的应用

由于烃及非烃微渗漏而形成的多种不透明特态矿物普遍存在于柴达木盆地西部油区的油气藏（层）上覆地层中。根据这些矿物的存在与否、分布井段长短、含量多少和集合体的大小、形态特征等其与下伏油气层油气产量的关系，划分出3类特态矿物指标，用特态矿物指标预测区内新井的含油气性获得成功。特态矿物法还可用于正钻井的含油气性预测、老探区及老探井含油气性的重新认识、获工业油气流井（构造）再挖潜、成油环境预测和确定油气富集成藏时间等。

Canonical Correlation Analysis of Agronomic Characters of Brassica juncea in Western China

[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character （containing 18 variables） were verified, including yield characters （5 variables）, caulis characters （6 variables）, branch characters （3 variables） and pod characters （3 variables）. [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits.

Oil source and migration process in oblique transfer zone of Fushan Sag,northern South China Sea

The oblique transfer zone in the Fushan Sag, a syndepositional dome sandwiched between the Bailian and Huangtong sub-sags, has been the most important exploration target. The major oil observation occurs in the E_2l_1^(L+M) and the E_2l_3~U. 46 oil and rock samples reveal that the oil in the transfer zone is mostly contributed by the Bailian sub-sag, though the source rock conditions, hydrocarbon generation and expulsion histories of the Bailian and Huangtong sub-sags are similar. The E_2l_3~U oil, characterized by high maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, shows a close genetic affinity with the E_2l_3~b source rocks, while the E_2l_1^(L+M) oil, characterized by lower maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, is suggested to be derived from the E_2l_(1+2)~b source rocks. The homogenization temperatures of aqueous fluid inclusions, taking the burial history of the reservoirs into account, reflect that the oil charge mainly occurred from mid-Miocene to Pliocene in the oblique transfer zone. The oil transporting passages include connected sand bodies, unconformities and faults in the Fushan Sag. Of these, the faults are the most complicated and significant. The faults differ sharply in the west area, the east area and the oblique transfer zone, resulting in different influence on the oil migration and accumulation. During the main hydrocarbon charge stage, the faults in the west area are characterized by bad vertical sealing and spatially dense distribution. As a result, the oil generated by the Huangtong source rocks is mostly lost along the faults during the vertical migration in the west area. This can be the mechanism proposed to explain the little contribution of the Huangtong source rocks to the oil in the oblique transfer zone. Eventually, an oil migration and accumulation model is built in the oblique transfer zone, which may provide theoretical and practical guides for the oil exploration.