扬子板块西北边缘碧口增生体的形成与演化          下载免费PDF全文

霍勤知  曾俊杰  董玉书 《甘肃地质》2002,11(2):17-23

依据 1∶5万区域地质调查和科研成果 ,认为碧口增生体内部具“三层式”结构特点 ,在对碧口增生体内部物质组成、变形、变质特征及形成时代等方面研究的基础上 ,将碧口增生体的形成和演化划分为 5个阶段 :沟、弧、盆体系形成发展阶段、板块碰撞造山阶段、陆内伸展和陆盆形成阶段、陆内逆冲推覆造山阶段、断块活动和差异性抬升阶段。  相似文献   

A Comparison of Two-Phase Dynamic Upscaling Methods Based on Fluid Potentials     

N.H. Darman  G.E. Pickup  K.S. Sorbie 《Computational Geosciences》2002,6(1):5-27

Although a number of methods for calculating dynamic pseudo-functions have been developed over the years, there is still a lack of understanding as to why a certain method will succeed in some cases but fail in others. In this paper, we describe the results of an assessment of several upscaling methods, namely the Kyte and Berry (KB) method, the Stone method, the Hewett and Archer (HA) method and the Transmissibility-Weighted (TW) method. We have analyzed the equations for deriving the methods and investigated the results of numerical simulations of gas displacing oil, in a variety of models to enable us to gain new insights into these, and related, upscaling methods. In particular, some novel observations on methods based on fluid potential are presented and the issue of using predicted fluid mobilities as a criterion of accuracy of an upscaling method is clarified.  相似文献   

吉林省大横路铜、钴矿床地质特征及控矿因素     

郭文秀  刘建民 《华北地质》2002,(Z1)

大横路地区出露地层主要为元古界老岭群大栗子组和珍珠门组的低绿片岩相 -高绿片岩相到低角闪岩相的变质岩系 ,北部有少量英云闪长岩 -奥长花岗岩和表壳岩残块。侵入岩主要以燕山期基性 -中基性为主。铜钴矿床产于含碳绢云千枚岩中 ,矿体长 36 0～ 140 0m ,宽 95～ 80 0m ,厚 3～ 10 8.7m ,呈层状、似层状、分枝状 ,矿石以浸染状为主 ,次为脉状、网脉状。矿床属多期多成因类型 ,主要受大栗子组地层、北东向断裂构造和变质作用控制 ,并有岩浆热液的叠加。  相似文献   

南秦岭横丹浊积岩系——晚古生代发育于扬子板块被动陆缘上的弧前盆地充填物     

闫全人  王宗起  A.D.Hanson  P.A.Druschke  王涛  闫臻 《地质通报》2002,(Z2)

南秦岭横丹浊积岩系是一套巨厚的浊流沉积,以向南或南东倾的单斜构造产出。由下而上,该沉积层序包括深水盆地、深水浊积扇和斜坡水道3个相序。相应地,沉积物粒度变粗,厚度变大,火山质组分含量增加,凝灰层大量发育,表明横丹浊积岩系为活动型浊积岩;其古水流方向为NNW—NNE向,物源区为南侧的碧口火山岩系。另外,横丹浊积岩系内还见石英岩、重结晶大理岩成分的砾石,说明其物源还包括被动陆缘环境的沉积物。相序、组构、沉积特征和物源区综合分析表明,横丹浊积岩系为弧前盆地充填物。构筑这一弧前盆地的动力学机制是洋壳板块向南俯冲于扬子板块被动陆缘之下,时代可能晚于中晚泥盆世。  相似文献   

Slump-initiated and controlled syndepositional sandstone remobilization: an example from the Namurian of County Clare, Ireland   总被引：1，自引：0，他引：1  

Lorna J. Strachan 《Sedimentology》2002,49(1):25-41

Remobilization of sandstones can dramatically reconfigure original depositional geometries and results in very unusually shaped sandstones, which resemble little, if any, of the original geometry. A number of deformational sandstone bodies, dykes and volcanoes from the upper part of the Carboniferous Ross Formation are described, which offer the opportunity to examine a suite of field-scale reconfigured sandstones. These structures are located in close proximity to the Ross Slide, which outcrops along a 2-km section on the northern coast of the Loop Head Peninsula, County Clare, Ireland. Dome- and ridge-shaped deformational sandstone bodies, dykes and volcanoes are interpreted to be the product of remobilization of a turbiditic sandstone. Liquification and remobilization were triggered by translation, cessation and loading of the underlying turbiditic sandstone by the Ross Slide. Deformational sand body, dyke and volcano development occurred in an asynchronous fashion with deformational sand bodies formed during slump translation. Sand dykes and volcanoes developed after the cessation of slump movement. During slump translation, the minimum principal stress (σ₃) was orientated vertically and the slump behaved in a `ductile' manner. After slump arrest, the minimum principal stress was oriented horizontally, and the unit regained shear strength to behave in a `brittle' manner. The relative change in rheological states with changing applied shear stress is indicative of thixotropic-like behaviour within the slump mass. Ridge-shaped deformational sand bodies are aligned parallel to slump folds, and their morphology is inferred to be controlled by compressional slump deformation associated with heterogeneous cessation of slump movement that was initiated by frontal arrest of the translating mass.  相似文献   

Experimental Study on Mine Spoils During Superficial Geochemistry Processes     

王一先  白正华 《中国地球化学学报》2002,21(4)

Based on the mineral and chemical compositions of spoils taken from the Shilu Cu-Mo deposit and Hetai gold deposit, the leaching and batch experiments were made on spoils taken from these two deposits using the leaching column designed by the authors. The experimental results showed that it is not always true that the mine drainage is acidic. Its acidity depends on acid-buffering capacity of gangue, host rock and its alteration mineral assemblage. The composition of the drainage water is related with the interaction between superficial or underground water and solid materials in the spoils, including minerals, hydroxides and amorphous substances. The leaching extent of the element is related with its occurrence form in the deposit. The preferential flow results in leaching-out of heavy metals in large amounts. So it is important to prevent the generating of preferential flow in the system. The results will provide very important grounds for the comprehensive management of land and ecological rehabilitation of the mine site.  相似文献   

新疆伽师及邻近地区现今地壳形变的GPS监测与研究   总被引：8，自引：2，他引：8       下载免费PDF全文

王晓强  王琪  程瑞忠  乔学军  李杰  张永岗  海力 《地震工程学报》2002,24(3):199-207

利用高精度数据软件对伽师及邻近地区的GPS监测网观测数据进行计算分析(基线精度达到了 10 - 8～ 10 - 9) ,获得了该地区的现今地壳形变速率图 .结果表明 ,伽师及邻近地区在印度板块的推挤作用下 ,地壳正快速缩短变形 ,主压应力为近南北方向 .各地块运动速率不同 ,平均应变率为 0 .0 4× 10 - 6 /a .  相似文献   

城市地区抗御地震灾害风险评估项目综述     

何玉林  韩渭宾  裴锡瑜  李广俊 《四川地震》2002,(4):35-38

城市地区抗御地震灾害风险评估项目系联合国在上世纪末为减轻地震灾害所实施的规模宏大，影响甚远的国际性研究项目，其宗旨是为了提高社会公众防灾意识，有效地减轻城市地区的地震灾害。这一历时2年的项目在有限的经费支持下，取得了令人瞩目的成绩。结合自贡市开展这个项目的实践。综合介绍和总结了该项目的情况及经验。  相似文献   

科技期刊发展的挑战与机遇   总被引：3，自引：0，他引：3  

薛宏交 《山西地震》2002,(3):43-45

中国加入世贸组织后 ,面对开放的世界性大市场的直接冲击 ,我国出版发行行业的竞争必将更加激烈。优胜劣汰 ,会直接考验每个出版社、每份期刊。为了使我国的期刊在竞争中成为胜者 ,探讨了科技期刊参与竞争的困难与优势 ,提出了如何提高我国科技期刊竞争力的粗浅看法  相似文献   

基于ODBC的地震前兆数据批量卸出与转换程序的实现     

李圣强  王斌  杨满栋  米宏亮  宋喜先  赵育浦 《华北地震科学》2002,20(2):22-27

介绍了CDBC技术、工作流程及数据传递方式；分析了研制数据卸出与转换程序的关键技术及实现方法；描述了程序的组织结构。通过实例说明了该程序在全国前兆台网中心卸载与转换地震前兆数字化的观测数据中的应用。  相似文献