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821.
渗流屏障为储层系统内遮挡流体渗流的岩体。以辽河西部凹陷某试验区于楼油层为例, 综合地质、400口井测井资料、6口取芯井岩芯资料、10口典型井水分析资料等多种资料, 详细研究了目的层渗流屏障的分类、发育规律以及对稠油热采储层开发的影响。从成因角度将研究区目的层扇三角洲前缘储层渗流屏障划分为沉积渗流屏障、成岩渗流屏障和封闭性断层渗流屏障等3种类型, 其中沉积渗流屏障占主导地位。受沉积作用控制, 沉积渗流屏障大体呈北东南西向条带状展布, 主要位于水下分流河道间泥和水下分流河道间砂的位置。从北西向南东方向, 随着与物源区距离逐渐增加, 沉积物粒度逐渐变小, 渗流屏障的发育程度也逐渐增强。渗流屏障的存在使得蒸汽驱热采过程中蒸汽的推进路径复杂化, 并进一步降低了蒸汽驱的热效率和经济有效性。渗流屏障的存在对分层注汽等开发措施的实施也具有十分重要的影响。 相似文献
822.
Nicolas Olivier Arnaud Brayard Emmanuelle Vennin Gilles Escarguel Emmanuel Fara Kevin G. Bylund James F. Jenks Gwnaël Caravaca Daniel A. Stephen 《Geological Journal》2016,51(4):600-626
This work focuses on well‐exposed Lower Triassic sedimentary rocks in the area of Torrey (south‐central Utah, USA). The studied Smithian 8 deposits record a large‐scale third‐order sea‐level cycle, which permits a detailed reconstruction of the evolution of depositional settings. During the middle Smithian, peritidal microbial limestones associated with a rather low‐diversity benthic fauna were deposited seaward of the tidal flat siliciclastic red beds. Associated with siliceous sponges, microbial limestones formed small m‐scale patch reefs. During the late middle to late Smithian interval, the sedimentary system is characterized by tidal flat dolostones of an interior platform, ooid‐bioclastic deposits of a tide‐dominated shoal complex, and mid‐shelf bioclastic limestones. Microbial deposits, corresponding to sparse stromatolites formed in the interior platform, are contemporaneous with a well‐diversified marine fauna living in a seaward shoal complex and mid‐shelf area. The nature and distribution of these Smithian microbial deposits are not related to any particular deleterious environmental condition, highlighting that observed patterns of biotic recovery after the end‐Permian mass extinction were directly influenced by depositional settings. Facies evolution and stratal stacking patterns allow us to identify large, medium and small‐scale, as well as elementary depositional sequences. Large‐ and medium‐scale sequences are consistent with sea‐level changes, whereas small‐scale and elementary sequences are better explained by autocyclic processes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
823.
824.
以国内某超稠油油藏为基础,应用二维物理模拟装置开展了蒸汽辅助重力泄油(SAGD)对比实验,研究了溶剂辅助SAGD技术对SAGD蒸汽腔发育特征、原油产量以及采收率的影响。研究结果表明,溶剂辅助SAGD中,溶剂以液相和气相共同存于油藏中,溶剂浓度越高,气相组分含量越高;溶剂中的气相组分在油藏中可以减少蒸汽在上覆岩层的热损失,提高蒸汽腔垂向扩展均匀性;合理溶剂浓度下,溶剂辅助SAGD可以显著提高峰值产量;低浓度溶剂辅助SAGD的单位原油产量的能耗明显低于纯蒸汽SAGD。实验结果表明,低浓度溶剂辅助SAGD对于开采超稠油油藏具有较大的应用潜力。 相似文献
825.
826.
历史上采用地方时间(如地方视太阳时、平太阳时等)观测和记录的某些天象的时刻,可用于地球自转速率变化的研究.日本在17—19世纪间有许多月球朔和望时刻的观测记录.本文简要介绍了其记载情况,探讨了将这些年代较晚的观测资料用于地球自转速率变化研究的可能性.试算结果表明他们对研究此期间地球自转速率的变化可起到积极作用.有必要对他们作更深入的研究. 相似文献
827.
Extinction considerations for diadromous fishes 总被引:1,自引:0,他引:1
828.
SQ高温高压无固相无相钻井液是一种由加重剂、粘度调节剂、缓蚀剂和除氧剂组成的无机钻井液,它对储层渗透率的恢复值高( 比现有的钻井液高出10% ~13 % ) ,具有腐蚀性弱(0.049mm/a) 、与地下水和CO2 等混合后不产生沉淀、耐高温( > 80 ℃) 、密度高(1 .51 ~1 .70g/cm3)等特性,故对油气层和机械设备具有良好的保护作用,是一种应性强的大型油田钻井液。 相似文献
829.
针对金山店铁矿亟需确定的大断面结构参数问题,采用东北大学研制的SLS崩落放矿模拟系统和ITASCA公司的岩土工程软件FLAC3D,对该矿三期的采场结构参数进行了模拟分析和研究。数值放矿试验表明,崩矿步距对矿石回收指标影响较大,崩矿步距3.5~4.5 m更有利于指标回收,兼顾爆破参数因素时推荐为3.5 m。通过进路群开挖的数值模拟,并对开挖过程围岩的位移、应力和塑性区进行分析,发现开挖后塑性区范围不大,巷道具有良好的稳定性。因此,拟采用的进路参数从矿石回收指标和巷道稳定性方面看是较合理的方案。 相似文献
830.
Anachronistic facies in the Lower Triassic of South China and their implications to the ecosystems during the recovery time 总被引:3,自引:1,他引:2
The end-Permian mass extinction not only severely distressed the Paleozoic ecosystems but also dramatically changed the sedimentary systems, resulting in a peculiar Early Triassic ecosystem and submarine environment during the recovery time following the mass extinction. The Lower Triassic is characteristic of the wide occurrence of various distinctive sediments and related sedimentary structures, such as flatpebble conglomerates, vermicular limestone, subtidal wrinkle structures, microbialite, carbonate seafloor fans, thin-bedded limestone and zebra limestone-mudstone. These sediments were common in the Precambrian to Early Ordovician marine settings, and then they occurred only in some extreme and unusual environments with the expansion of metazoan faunas. However, the Early Triassic witnessed an "anachronistic" reappearance of some distinctive sedimentary records in normal shallow marine settings. The study of these anachronistic facies should be of great importance for the understanding of the unique ecosystem and marine environment through the great Paleozoic-Mesozoic transition. The anachronistic facies characterized by vermicular limestone have been documented in many localities in South China and occur at various horizons of the Lower Triassic. Most types of re- ported distinctive sediments over the world have been observed in the Lower Triassic of South China. This provides an excellent opportunity for understanding the Early Triassic environment and its co- evolution with the biotic recovery. Among the anachronistic facies the vermicular limestone is the most characteristic and common distinctive sediments in the Lower Triassic of South China but has received relatively few investigations. Taking it as a case study, we will detail the variation of vermicular limestone and its stratigraphic distribution in the Three Gorges area, Hubei Province. The investigation on the vermicular limestone and other distinctive sediments from the Lower Triassic of South China further indicates that the appearance of anachronistic facies immediately following the mass extinction and the elimination from normal shallow marine facies with the radiation of Mesozoic marine faunas imply the natural response of the sedimentary systems and ecosystems to the great Paleozoic-Mesozoic transitional events and their induced harsh environments. Therefore, the ups and downs of the anachronistic facies may act as a proxy for the evolution of ecosystems independent of fossil analyses. 相似文献