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991.
李敏 《物探化探计算技术》2012,34(4):425-430,367
充分运用地震资料,可以提高沉积相划分及储层砂体识别的精度和准确性.通过对测井、地震资料的分析,将辛斜164井区沙三中亚段划分成中9、中8、中7、中6、中5、中4、中3、中2、中1等九个沉积期次.参考地震属性分析,将每个准层序的三角洲又分为三角洲平原、三角洲前缘及前三角洲三个亚相,并描述了沙三中亚段的主要储集体性能.根据沉积相、储集体性能与波阻抗研究,提出了有利勘探区.地震资料及地震属性有助于三角洲沉积相及储层的研究.  相似文献   
992.
从鄂尔多斯盆地西部前陆盆地的构造演化特征入手,通过对鄂尔多斯西南缘前陆冲断带汭河—陇县—麟游露头剖面和前陆斜坡带延河剖面上三叠统延长组典型露头剖面的观测与对比,以及显微镜薄片分析,讨论了鄂尔多斯盆地西南缘前陆不同构造带在沉积层序演化、砂体展布及储层微观特征等方面的差异及主控因素。认为鄂尔多斯盆地西南缘延长组长10—长2下部油层组可划分为3个湖侵体系域和3个湖退体系域。沉积砂体集中发育在湖侵早期和湖退阶段。前陆冲断带近秦祁造山带物源区,坡度陡,砂体沉积受构造作用控制,发育近物源辫状河三角洲。三角洲快速入湖,砂体厚度大,砂岩粒度较大,岩屑、杂基含量较高,储层物性相对较差。前陆斜坡带距离北部阴山褶皱带物源较远,坡度缓,砂体沉积受湖岸线迁移控制,发育远物源曲流河三角洲。砂体展布范围大,沉积相变化频繁,砂岩粒度较小,杂基含量较低,后期成岩作用产生次生孔隙,可成为较好储层。  相似文献   
993.
Isotopic reference materials are essential to enable reliable and comparable isotope data. In the case of boron only a very limited number of such materials is available, thus preventing adequate quality control of measurement results and validation of analytical procedures. To address this situation a unique set of two boron isotope reference materials (ERM‐AE102a and ‐AE104a) and three offset δ11B reference materials (ERM‐AE120, ‐AE121 and ‐AE122) were produced and certified. The present article describes the production and certification procedure in detail. The isotopic composition of all the materials was adjusted by mixing boron parent solutions enriched in 10B or 11B with a boron parent solution having a natural isotopic composition under full gravimetric control. All parent solutions were analysed for their boron concentration as well as their boron isotopic composition by thermal ionisation mass spectrometry (TIMS) using isotope dilution as the calibration technique. For all five reference materials the isotopic composition obtained on the basis of the gravimetric data agreed very well with the isotopic composition obtained from different TIMS techniques. Stability and homogeneity studies that were performed showed no significant influence on the isotopic composition or on the related uncertainties. The three reference materials ERM‐AE120, ERM‐AE121 and ERM‐AE122 are the first reference materials with natural δ11B values not equal to 0‰. The certified δ11B values are ?20.2‰ for ERM‐AE120, 19.9‰ for ERM‐AE121 and 39.7‰ for ERM‐AE122, each with an expanded uncertainty (k = 2) of 0.6‰. These materials were produced to cover about three‐quarters of the known natural boron isotope variation. The 10B enriched isotope reference materials ERM‐AE102a and ERM‐AE104a were produced for industrial applications utilising 10B for neutron shielding purposes. The certified 10B isotope abundances are 0.29995 for ERM‐AE102a and 0.31488 for ERM‐AE104a with expanded uncertainties (k = 2) of 0.00027 and 0.00028, respectively. Together with the formerly certified ERM‐AE101 and ERM‐AE103 a unique set of four isotope reference materials and three offset δ11B reference materials for boron isotope determination are now available from European Reference Materials.  相似文献   
994.
北部湾盆地涠西南凹陷WZ油田古近系流沙港组一段是主要含油层系,实钻表明储集层成因复杂、厚度变化大、非均质性强,致使砂体分布预测困难。通过精细的岩心观察,结合各类测井、录井及岩心分析化验资料综合研究,认为流一段属陡坡型扇三角洲沉积,主要发育扇三角洲前缘亚相,其中夹杂有丰富的重力流沉积。扇三角洲前缘亚相主要由水下分流河道、河口坝、远砂坝和河道间沉积微相组成;重力流沉积包括重力滑塌沉积、碎屑流沉积、浊流沉积及液化流沉积,规模均较小。在深入的单井沉积微相分析和多井对比基础上,编制了流一段主力Ⅳ油组和Ⅱ油组的沉积微相平面图,展示出研究区总体沉积格局为稳定的扇三角洲前缘环境,物源充分,主要来自北部和西北部,因斜坡带较陡,在扇三角洲前缘至前扇三角洲环境发育丰富的各类重力流沉积。根据各沉积微相的特征与展布,建立了本区较深水陡坡型扇三角洲沉积模式。分析了不同微相砂体的物性与含油性,认为扇三角洲前缘水下分流河道砂体最好,其次是河口坝砂体,远砂坝和远端浊积砂体相对较差。提出了有利的挖潜区域和调整井位,实钻遇油层数十米,为油田增储上产发挥了重要作用。  相似文献   
995.
根据长江三角洲南部平原12个柱状样(各柱样长2.5m)沉积物中总硫(TS)、总有机碳(TOC)含量、Cl-浓度及pH值,计算湖沼平原、三角洲平原和现代潮滩3个沉积地貌区TS/TOC散点回归线的斜率,并分析长江口硫元素分布的主要影响因素,检验TS/TOC在研究区识别咸水、淡水沉积环境的可行性。研究结果显示,三角洲平原的 7个剖面(H2~H8)TS/TOC平均值0.026~0.044,TS与 TOC具有良好的相关性,回归线斜率0.027;湖沼平原区的3个剖面(H10~H12)TS/TOC平均值为0.029~0.032,TS与TOC回归线斜率为0.037。而位于杭州湾现代潮滩的H9剖面TS/TOC呈现显著高值,平均值为0.130,回归线斜率达到最大值0.117;崇明岛现代潮滩的H1剖面TS/TOC平均值为0.055,回归线斜率为0.054,明显高于前述淡水环境,反映了海水对TS的影响,也显示了TS/TOC指标可能是该区比较有效的咸淡水环境判别工具。另外,长江口的TS/TOC比值和TS-TOC散点回归斜率明显低于世界其他半咸水海岸带沉积,指示了大河口淡水径流作用强烈的区域性特征。  相似文献   
996.
渤海湾西岸的几道贝壳堤   总被引:2,自引:1,他引:1  
渤海湾西岸出露或埋藏了多道贝壳堤,通过地质调查发现:贝壳堤的平面分布结构是沿着(或随着)渤海湾海岸由老至新(从岸—海)与海岸呈大致平行排列。贝壳堤的划分方案有两种,一种是从新至老,另一种是从老至新,本文采取后一种划分方法:即第Ⅰ道(老)—第Ⅵ道(新)贝壳堤。本文对每道贝壳堤的物质(岩性特征)组成与堆积特征进行了描述(图2~图7);对贝壳堤的几何形态特征进行了数理统计(表2);对贝壳堤形成的年代特征进行了对比分析(表3);对贝壳堤的生物组合特征等资料进行了归纳和整理;对贝壳堤的分道方案进行了对比分析(表1),揭示了贝壳堤的赋存状态、形成的年代及第Ⅰ道—第Ⅵ道贝壳堤所处的潮位变化(图8)。以形成贝壳堤这一独特的地质载体为基础,试图从渤海湾宏观整体的角度分析并揭示贝壳堤的成因机制(表4,图9),笔者认为广义的渤海湾是内陆的半泻湖(海),也可以视为局部海:山东庙岛列岛—辽东半岛构成了渤海的障壁海岸,在障壁海岸这样的自然地理和地貌条件下,通过大量的资料综合分析认为只有障壁海岸才是形成"科珀河型三角洲与喙状三角洲"的必然条件,而"科珀河型三角洲与喙状三角洲类型"等是形成障壁砂坝(障壁岛,障壁滩)—贝壳堤的或然条件,这就是贝壳堤成因的主要机制。  相似文献   
997.
Beach heights and tidal variation have large impacts on the accuracy of estimates of coastline position and its historical changes of a wider and flatter beach based on remote sensing data. This study presents an approach to analysis of waterline movement based on the beach slope, estimated from two effective images with Landsat images data. Two images acquired at different stages of the tide were processed to delineate accurately the position of the waterline. Then waterlines were assigned heights using elevations predicted by a two-dimensional non-linear tidal assimilation model. Beach slope can be calculated piecewise using the heighted shorelines based on the equiangular triangle theory. The positions of the national tidal height datum coastline can be obtained by the beach slope calculation method to accurately monitor the changing of coastline. A change in the coastline of the southwest tidal flat of the Yellow River delta, from Tianshuigou to the Xiaoqing River mouth, was detected by combining field measurements of profiles and bathymetric data. The root mean squared error (RMSE) of the calculated slope of the intertidal zone was one order of magnitude less than the measured slope. The minimum error of self-consistency check is 0.2%. The RMSE between the coastlines estimated by the proposed method and those surveyed data varies from 53.98 m to 217.72 m. It is shown that this method is more suitable for the two years and over the time scales of shoreline change monitoring. To assess erosion/accretion patterns in the tidal flat, and the controlling factors, the volume of the beach was investigated as a possible indicator. The accepted coastline position and changes in the beach volume were used to monitor the changing pattern of accretion and erosion along the coast southwest of the recent Yellow River mouth.  相似文献   
998.
Glacial erosion has caused overdeepening of many alpine valleys. After retreat of the ice, they were filled with heterogeneous deposits of glacial, lacustrine and fluvial sediments. A typical example of such a valley segment and its infill is the Reuss delta on the southern shore of Lake Lucerne in Switzerland. To obtain a detailed three‐dimensional image of this valley segment, the ETH Institute of Geophysics has acquired several two‐dimensional, high‐resolution seismic and georadar profiles, and conducted a three‐dimensional georadar survey. Interpretations of these geophysical data were constrained by a geological core extracted from a borehole 300 m deep near the investigation site. The seismic profiles imaged ca. 600 m of sediment infill above bedrock. Based on their reflection characteristics, five different deposition units were distinguished. These units were interpreted as a succession of clay/silt at the base, followed by different sand units with variable but generally increasing amounts of gravel. This succession represented a prograding delta that filled the southern part of Lake Lucerne. The latest fluvial development of the region is best represented by the georadar data. In particular, the three‐dimensional georadar data set provides a detailed view of an ancient braided river channel Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
999.
以羌北坳陷龙尾错地区雪山组地层为例,通过对沉积物来源、古生态、碳氧同位素、粒度特征及其沉积序列、古水流向的研究,揭示了上侏罗统—下白垩统雪山组地层沉积时期的沉积环境及古地理格局,认为该区雪山组地层是在中央隆起带露出水面并向羌北地区提供物源的古构造—地理条件下形成的三角洲沉积体系,具辫状河成因的显著特点。  相似文献   
1000.
鄂尔多斯盆地东部山西组海相沉积环境分析   总被引:14,自引:1,他引:13  
以地球化学指标为主,结合地层古生物和原生沉积构造等各方面的证据,进一步分析了鄂尔多斯盆地东部山西组的沉积环境。泥岩样品的地球化学特征表明,由于受潮汐和海侵作用的影响,整个山西期盆地东部的沉积水体以混合水为主,其中硼元素反映了基准面长期旋回的变化特征,而Sr/Ba则是超长期的变化指标;从沉积构造和海相化石分布特征可知,在山西早期中等强度的潮汐作用直接影响了研究区的东南部,对三角洲沉积进行改造,到了山西中晚期三角洲进积作用增强,潮汐作用范围逐渐退至研究区东南缘;此外,地层的分布特点和沉积相也说明在整个山西期盆地东部地层和晋西地层联片沉积且属于同一三角洲沉积体系,东部的水下隆起还不足以阻隔水体形成湖盆,所以鄂尔多斯盆地东部山西组是发育在浅海陆棚基础上的三角洲沉积。  相似文献   
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