对秦岭奥长环斑花岗岩的质疑   总被引：13，自引：2，他引：13       下载免费PDF全文

赵玉平 《地质论评》2001,47(5):487-491

本文介绍了环斑结构的含义及奥长环斑花岗岩的地质与地球化学特征。在此基础上对所谓的秦岭奥长环斑花岗岩带提出质疑，并提出秦岭中的一些花岗岩虽然具有环斑结构，但不是奥长环斑花岗岩。  相似文献   

A Study of Sr, Nd and O Isotopes of the K-rich Melanocratic Dykes in the Late Mesozoic Gold Field in the Jiaodong Peninsula   总被引：2，自引：1，他引：2  

SUN Jinggui  HU Shouxi  LIU Jianmin  SHEN Kun  LING Hongfei Earth Science Institute  Jilin University  Changchun State Key Laboratory of Research on Metallogenesis of Endogenic Ore Deposits  Nanjing University  Nanjing Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing Shandong Institute  Laboratory of Geological Sciences  Jinan 《《地质学报》英文版》2001,75(4):432-444

Geologic, petrographic and petrochemical studies of the late Mesozoic K-rich melanocratic dykes, including lamprophyres, andesite porphyrites and dacite-porphyry in the gold field system in the Jiaodong Peninsula, China, have shown that these dykes are characterized by rich potassium and alkali but poor titanium. They belong to an ultra-high potassic, shoshonitic and high potassic calc-alkaline rock series. The parental magma has relatively high initial strontium ratios ((87Sr/86Sr)i=0.70895-0.71140) and low (143Nd/144Nd)i ratios (varying from 0.51135 to 0.51231); and its δ18OSMow. whole rock values vary from +5.8‰ to +10.6‰ with a mean of+7.1‰. These features suggest that the source region of the magma is an enriched mantle wedge transformed from a continental lithosphere mantle which has experienced metasomatism by mantle-derived fluids with H2O-dominated fluids that were provided during the underthrusting of an ocean crust. The initial magma was generated by low-degree partial melting of the enri  相似文献   

Rock Series and Genetic Types of Granitoids in the Western Kunlun Orogenic Belt, China   总被引：2，自引：0，他引：2  

JIANG Yaohui  ZHOU Xunruo  RUI Xingjian  QUO Kunyi  HE Jurui  YANG Wanzhi State Key Laboratory of Mineral Deposit Research  Nanjing University  Nanjing  Jiangsu Nanjing Institute of Geology  Mineral Resources  Ministry of Land  Resources  Nanjing  Jiangsu China University of Geosciences  Beijing Xinjiang Geophysical  Geochemical Exploration Team  Changji  Xinjiang 《《地质学报》英文版》2001,75(1):19-26

A systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun erogenic belt. The study indicates that the granitoids belong to tholeiitic, calc-alkaline, high-K calc-alkaline, alkaline and shoshonitic series, and that there are 5 genetic types, i.e., I-, S-, M-, A- and SH-type, of which SH-type is first put forward in this paper, which corresponds to shoshonitic granitoids.  相似文献   

Water Resource Development in the Quaternary Ryukyu Limestone Regions of Japan:Application of the GIS to the Site Selection of Underground Dams     

Kaijun JIANG  Hiroyasu FURUKAWA  Yuji ONOYAMA  Testuro ESAKI 《《地质学报》英文版》2001,75(3):254-259

Based on the natural and social conditions as well as hydrogeological characteristics of the Ryukyu limestone, a major aquifer in the Ryukyu Islands, a conception of underground dam, was proposed in the early 1970s in order to develop ground water resources in the Quaternary Ryukyu limestone regions of Japan. The practice of nearly thirty years has shown that the underground dam is an environment-friendly and effective way for developing ground water in these regions.To further improve the technology associated with underground dam, the authors introduced related analytic methods. The application of the geographical information system technology to site selection of the underground dam is reported in this paper.  相似文献   

辽河盆地西部凹陷沙河街组西八千扇体   总被引：6，自引：4，他引：6  

孙素青 《古地理学报》2001,3(2):92-98

利用丰富的钻井、测井、地震等资料，以层序地层学理论为指导，将辽河断陷西部凹陷发育的老第三系沙河街组划分为3个层序7个体系域，并以体系域为单元描述西八千扇体的沉积体系类型、沉积作用特点、空间分布及其演化。在不同层序发育过程中，各因素所起的作用有主次之分。沉积速率和构造沉降是湖泊水深变化的主要控制因素；构造因素对层序Ⅱ的旋回性和特殊的沉积充填样式等起主导作用；在构造作用相对平稳的层序Ⅲ发育时期，气候因素的影响通过多个准层序叠加及湖平面频繁变化表现出来。  相似文献   

静水条件下背斜圈闭系统石油运移和聚集模拟实验及机理分析   总被引：1，自引：0，他引：1       下载免费PDF全文

曾溅辉  王洪玉 《地质论评》2001,47(6):590-595

静水条件下背斜圈闭系统石油运移和聚集的模拟实验表明：（1）不同砂层组合方式的背斜圈闭系统中，油的运移方向、路径和通道不同，其中，均质和反韵律砂层组成的背斜圈闭系统油的运移方向、路径和通道比较简单，而正韵律组成的背斜圈闭系统中油的运移方向、路径和通道比较复杂；（2）油的充注速率对油的运移方向、路径和通道具有重要的影响，当充注速率较小时，油仅在一些渗透率较高的砂层中运移，当充注速率较大并超过渗透率较高的砂层的运载能力时，则油可以进入一些渗透率较低的砂层；（3）运载层的岩性组合和渗透率级差以及油充注速率和充注方向等对油气运移的散失量和运移效率产生重要的影响，一般来说，反韵律砂层组成的背斜圈闭系统中油的运聚效率较高，均质砂层组成的背斜圈闭系统次之，而正韵律砂层组成的背斜圈闭系统中油的运聚效率比较低；（4）油的运移形式表现为跳跃和脉动的特点。  相似文献   

不确定分析技术中的多项式正态转换方法研究     

陆宝宏  陆玉忠等 《水文》2001,21(6):4-7

不确定性及可靠性分析技术已广泛应用于水利及土木系统工程分析中，可靠性计算的核心之一是对随机变量进行正态转换。对土木工程系统不确定性及可靠性分析中有着潜在应用前景的非正态随机变量的多项式正态转换方法进行了研究，通过在各种条件下非正态随机变量的正态多项式转换成果之评价，发现在水利及土木工程可靠性分析中常用的许多分布可以保留其自身的比较好的特征。  相似文献   

LINKING SEDIMENT EXPOSURE WITH EFFECTS: MODELING TECHNIQUES, ORGANIC AVAILABILITY AND UPTAKE     

Xiaoxia LU  Danny REIBLE 《国际泥沙研究》2003,(2)

1 INTRODUCTION Sediments are the ultimate sink for many hydrophobic contaminants and represent biologically important environmental habitats. Exposure of the sediment-associated contaminants is not only influenced by the fate and transport of sediment but also is influenced by a variety of physical, chemical, and biological processes that involve no net movement of sediments. These processes include pore water transport processes such as advection and diffusion, and sediment mixing process…  相似文献   

Deep structural characteristics and seismogenesis of the M≥8.0 earthquakes in North China     

张先  张先康  刘敏  赵丽 《地震学报(英文版)》2003,(2)

Introduction North China is a seismically active area in the eastern part of China, where four M8.0 earthquakes have been recorded in the historical documents and confirmed by the researchers. The first is the M=8.0 earthquake occurred in A.D. 1303 in Hongtong, Shanxi Province. It was the ear-liest M=8.0 earthquake recorded in the historical document in China. The second is the M=8.0 earthquake occurred in A.D. 1556 in Huaxian County, Shaanxi Province. The other two are the M=8.5 earth…  相似文献   

洋山港海域现代沉积物运移趋势          下载免费PDF全文

李玉中  陈沈良 《地质学报》2003,77(3):423-431

地形、物源和水动力条件是洋山港海域现代沉积环境的主要控制因素，粉粒和粘粒是现代沉积物的主要组成部分，潮流是起动和搬运现代沉积物的主要动力，悬移是现代沉积物最主要的搬运方式，跃移是次要搬运方式，现代沉积物的起动和沉积过程交替频繁。研究区现代沉积物长期净运移趋势表明：研究区东部的黄泽洋向洋山港海域的输沙趋势显著；洋山港岛链峡道深槽的形成，系由峡道东部和西部的现代沉积物各向峡道两端分异运移所致；小洋山—唐脑山—线将是今后港区泥沙淤积的主要部位之一。  相似文献