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141.
为了明确准噶尔盆地腹部莫索湾地区清水河组储层特征及其成因,综合利用铸体薄片、扫描电镜、物性、X衍射等多种分析测试手段,并结合钻测井、地层测试资料及区域埋藏史、古地温、沉积体系等相关研究成果,详细分析了清水河组储层成岩作用特征及其物性控制因素,并在此基础上总结成岩模式。研究结果表明:清水河组储层具有低成分成熟度、高塑性岩屑含量及高结构成熟度的"一低两高"特征;尽管储层主体埋深在3 500m以下,但储集空间仍以原生粒间孔为主,平均孔隙度为15.47%,平均渗透率可达226.6mD,为典型的深层优质储层;储层成岩作用总体表现为"中压实中强压实、强溶蚀、弱胶结"的特征,尽管储层埋深较大,但成岩阶段整体仍处于中成岩A1亚期;区域连片的厚层辫状河三角洲前缘水下分流河道及河口坝中细砂岩及中粗砂岩是形成深层优质储层的基础,而成岩过程中储层物性保存主要受控于早期碳酸盐胶结抗压实、绿泥石包壳及后期酸性成岩流体条件下的溶蚀增孔作用;除上述沉积、成岩控制因素外,地层超压的存在使得储层在深埋条件下压实强度显著降低,是储层物性保存的关键,同时在储层成岩演化过程中及现今盆地不断降低的地温梯度也有效延缓了储层的成岩进程。 相似文献
142.
Gaps between beam‐to‐column interfaces in a post‐tensioned (PT) self‐centering frame with more than one column are constrained by columns, which causes beam compression force different from the applied PT force. This study proposes an analytical method for evaluating column bending stiffness and beam compression force by modeling column deformation according to gap‐openings at all stories. The predicted compression forces in the beams are validated by a cyclic analysis of a three‐story PT frame and by cyclic tests of a full‐scale, two‐bay by first‐story PT frame, which represents a substructure of the three‐story PT frame. The proposed method shows that compared with the strand tensile force, the beam compression force is increased at the 1st story but is decreased at the 2nd and 3rd stories due to column deformation compatibility. The PT frame tests show that the proposed method reasonably predicts beam compression force and strand force and that the beam compression force is 2 and 60% larger than the strand force with respect to a minor restraint and a pin‐supported boundary condition, respectively, at the tops of the columns. Therefore, the earlier method using a pin‐supported boundary condition at upper story columns represents an upper bound of the effect and is shown to be overly conservative for cases where a structure responds primarily in its first mode. The proposed method allows for more accurate prediction of the column restraint effects for structures that respond in a pre‐determined mode shape which is more typical of low and mid‐rise structures. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
143.
Wei Che Qifeng Luo School of Engineering & Technology China University of Geosciences Beijing China 《地震学报(英文版)》2010,(1)
The rotational seismic motions are estimated from one station records of the 1999 Jiji (Chi-Chi), Taiwan, earthquake based on the theory of elastic plane wave propagation. The time-frequency response spectrum (TFRS) of the rota-tional motions is calculated and its characteristics are analyzed, then the TFRS is applied to analyze the damage mechanism of one twelve-storey frame concrete structure. The results show that one of the ground motion components can not reflect the characteristics of the seismic moti... 相似文献
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145.
Establishing a monitoring network for an impoundment-induced landslide in Three Gorges Reservoir Area, China 总被引:2,自引:1,他引:1
A methodology for monitoring system of an impoundment-induced landslide in Three Gorges Reservoir Area, China is introduced.
Currently, based on landslide geological classification, the monitoring regions and methods which include types of monitoring
instruments, placement and calibration precision of instruments, and appropriate periods for instrumental placement is confirmed.
To optimize the monitoring system, sensitivity analysis of displacements and the water table in landslides affected by reservoir
surface fluctuation is completed to determine the layout of the monitoring cross sections and the monitoring points. As a
case study, the behavior of displacements and the potential fluctuation of the water table in the Shiliushubao landslide,
produced by the gradual water impoundment at Three Gorges Reservoir, has been simulated using 3D finite element method analysis.
The sensitivity analysis of Shiliushubao landslide is investigated by the fuzzy set evaluation method. As a result, the monitoring
network of Shiliushubao landslide is established. 相似文献
146.
本文以吉林夹皮沟金矿带为例,通过板块碰撞或旋转所产生的磁斥力和电场来探讨流体中成矿元素运移和富集机制。基于块体转动与岩石剩磁磁斥力的产生,岩石电、磁场的形成和阴 阳离子相向漂移的地质证据及成矿流体与磁感应矢量、电导率间对应关系的讨论,表明:1)成矿元素的富集发生于新旧电、磁场交替变化过程中;2)岩石电场正、负极控制阴、阳离子作相向漂移运动,是流体中成矿元素运移、富集的主要控制因素之一;3)深大断裂界面间的磁斥力是Au、Ag、Cu、Pb和Zn等有色多金属抗磁性元素成矿的有利场所。 相似文献
147.
地壳放气动态监测与张北—尚义Ms6.2级地震预报 总被引:8,自引:0,他引:8
笔者从新的地球观出发,论述地壳放气与地震活动的关系,及其在张北-尚义Ms6.2级地震中短期,短临预报中应用,认为地震是可以预报的。因此,笔者提出地震预报探索中应加强地壳放气动态监测与研究,特别是加强断层带土壤气CO2、H2,He与Hg动态监测的观点。 相似文献
148.
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150.
北京什刹海生态修复试验工程 总被引:43,自引:4,他引:39
什刹海是北京市一个小型浅水城市风景游览的富营养湖泊.生态恢复试验工程以物理除藻为前提,通过实施基底修复而后开展水体充氧等手段,达到恢复水生植被的根本目的.应用的修复技术有:(1)臭氧/超声波除藻;(2)基底修复;(3)水下曝气充氧及冬季冰下底部充氧;(4)上游区复合生物浮床;(5)水下光补偿技术;(6)高等水生植物栽植与优化配置;(7)水生植物调控与机械割草;(8)水质净化与保洁管理.工程实施近1年(2001年8月-2002年6月)后效果明显,总氮、总磷分别下降了4.74mg/L和0.45mg/L,去除率达到79%和91%,什刹海的水质也由Ⅴ类上升为Ⅳ类. 相似文献