三江中段新特提斯阶段区域流体的性质与状态   总被引：17，自引：3，他引：14  

徐启东  莫宣学 《岩石学报》2000,16(4):639-648

对西南三江地区中段各类脉体开展了系统的流体包裹体和部分稳定同位素成分的研究,探讨新特提斯阶段区域流体状态及对区域成矿条件的影响,研究表明,三江中段新特提斯阶段区域流体存在两个性质不同的流体作用区域,中咱地块以西的兰坪盆地和澜沦江－金沙江构造带主要属于低温流体和域,区域流体以ＮａＣｌ类－Ｈ２Ｏ体民分为特征,中低盐度,流动和沉淀过程中的温度不高于２８０℃,其水体部分主要来自大气敢水的下渗和汇聚,中咱地  相似文献   

Triassic Orogenesis in Southwest China: the Structural Origins of the Northeast Tibetan Plateau     

Mathew J. Harrowfield  Christopher J.L. Wilson WT  ”BX 《地学前缘》2000,(Z1)

TRIASSIC OROGENESIS IN SOUTHWEST CHINA: THE STRUCTURAL ORIGINS OF THE NORTHEAST TIBETAN PLATEAU  相似文献   

关于老工业基地淄博市工业区位变化的地理学思考   总被引：1，自引：0，他引：1  

祁苑玲  王缉慈  任宝 《地理科学》2006,26(1):7-12

在经济全球化和技术飞速进步的影响下,改革开放以来,在我国老工业基地内部出现了新的工业区位并形成了新的产业集聚区。引起变化的因素是多方面的。以淄博实地调研为基础,分析了这种变化产生的动因。淄博市新工业区域的形成从一个侧面说明老工业基地的发展潜力。在改革开放以后,国有企业自主权扩大以及大量非公有制的企业繁衍成为淄博工业发展的内动力,引起工业地理格局的变化。自然资源对工业区位的吸引力下降,专业市场区位的重要性上升,在淄博市的工业空间动态中反映也很显著。此外,政府因素和交通区位仍然起重要作用。企业在新工业区位的繁衍和集聚是老工业基地的活力所在,需要特别予以关注。  相似文献   

新疆蛇绿岩时空分布特征及对增生造山过程的制约     

赵同阳  朱志新 《新疆地质》2021,(1):21-29

聚焦新疆区内集中出露的61处蛇绿岩,据其物质组成、构造属性、形成时代、空间分布等特征,将其划分为14条蛇绿混杂岩带,其中多处发育洋岛海山、洋内弧等大洋岩石圈岩石组合,并以塔里木-敦煌地块为界,提出以北属古亚洲洋构造域、以南属特提斯洋构造域.结合俯冲增生造山过程中不同阶段的岩石学记录,确认古亚洲洋形成于新元古代末期至晚石...  相似文献   

浅谈大田县硫铁矿资源现状及开发利用对策     

颜洪泉  施生文 《化工矿产地质》1999,21(2):121-124

作为老矿山,面临资源等自身条件及外部环境而出现的困难,福建省大田县硫铁矿针对自身资源特点,加大科技投入,通过深入开展对矿区地质、资源开发利用技术等项研究,运用科学技术开发新产品,不断提高资源利用水平。从而获取了良好的经济效益,使资源开发利用进入良性循环。  相似文献   

三江地区两类古陆成分的铅同位素组成——Ⅰ.碳酸盐岩类          下载免费PDF全文

徐启东  夏林 《地球科学》1999,24(3):274-277

根据铅同位素组成,西南三江地区前中生代的碳酸盐岩可分成具高放射性和低放射性成因的铅同位素特征的两种类型,其数值范围和样品的空间分布都可分别与已知的冈瓦纳和劳亚古陆群的铅同位素组成对比。运用不同古陆群显示的块体铅同位素组成差异作为标志,判别兰坪盆地中以灰岩和细碎屑岩组成的上三叠统可能不是中生代兰坪盆的沉积产物,而是新生代早期从盆地西部冈瓦古陆群中逆冲推推覆过来的构造岩片。  相似文献   

Geochemistry of the Caledonian basic volcanic rocks at the south margin of the Qinling orogenic belt, and its tectonic implications   总被引：1，自引：0，他引：1  

Dong Yunpeng  Zhou Dingwu  Zhang Guowei  Zhu Bingquan 《中国地球化学学报》1999,18(3):193-200

The geochemistry of the basic volcanic rocks at the south margin of the Qinling orogenic belt(SMQOB) suggests that they were formed in an intraplate tectonic setting.The REE distribution patterns show these rocks are strongly enriched in LREE with high ∑REE, and their trace elements geochemistry is similar to that of contimental flood basalt.All the above evidence suggests that the Caledonian basic volcanic rocks in the SMQOB were tholeiitic basalts formed in an intraplate spreading-initial rift tectonic setting.The characteristics of regional geology and geochemistry indicate that there was an intraplate spreading-rift tectonic setting between the South Qingling block and the Yangtze block in the Caledonian epoch.The dynamic spreading in this district began in the Early Caledonian and then the intraplate spreadinginitial rifts were formed in the Late Caledonian.As a result of spreading of the Tethys and geodynamic processes in deep mantle ,the Mianlue-Huashan oceanic basin was formed between the Qinling block and the Yangtze block in Devonian,and the Qinling microplate was separated from the northern part of the Yangtze plate.  相似文献   

乙醚硅胶柱反相萃取层析法分离和测定镓的研究   总被引：3，自引：0，他引：3  

郑亚西  陈鹰 《矿物岩石》1999,19(2):93-95

本文报道了用乙醚硅胶柱分离和测定镓的方法及其应用。以硅胶球为载体,乙醚为固定相,在６ｍｏｌ／Ｌ ＨＣｌ体系中定量萃取层析镓（Ⅲ）,用６ｍｏｌ／Ｌ ＨＣｌ作杂质淋洗液,１ｍｏｌ／Ｌ ＨＣｌ解脱镓,可使镓与多种离子分离,选择性高,镓回收率可达９７％以上。结合罗丹明Ｂ萃取光度法,用于地质样品中镓的分离、富集与测定,方法简便、快速、准确。  相似文献   

粤东及琼东北第四纪老红砂风成的若干证据     

王建华  梁致荣  郑卓  陈水挟 《热带海洋学报》1998,(1)

粤东及琼东北第四纪老红砂分布于全新世和现代海岸风沙强烈作用带,其野外产状、沉积构造与海滩砂不同,粒度、石英砂磨圆度、石英砂表面微结构统计、孢粉和硅藻等分析证明这些老红砂与海岸沙丘砂有着成因上的联系,热释光年代为距今1．62—5．19万a,故它们是毗邻海滩的海岸风成砂,形成于未次冰期的低海平面期,其形成和分布与盛行风和向岸风的共同作用有关。  相似文献   

Subsurface old drainage detection and paleoenvironment analysis using spaceborne radar images in Alxa Plateau   总被引：2，自引：0，他引：2  

GUO Huadong  LIU Hao  WANG Xinyuan  SHAO Yun  SUN Yan 《中国科学D辑(英文版)》2000,43(4):439-448

For geological and environmental research in an arid area, a unique advantage of radar remote sensing is that radar wave can penetrate a certain layer of dry sand (a few centimeters to meters thick) to reach the buried bedrock. The penetration capability is able to reveal the subsurface geological structure and old drainage paths. Based on the analysis of SIR-A, SIR-B, SIR-C, Radarsat ScanSAR, Landsat MSS and Landsat TM images acquired on different dates and the investigations made in several field trips in Alxa Plateau of Inner Mongolia, a number of old river valley and lake basins buried by wind-blown sand were recognized. Two parallel old drainage systems in the north and middle of the study area are delineated. The study suggests that the moving sand belts mainly follow the old drainage courses. This study also establishes a preliminary drainage evolution model for an area of about 300 000 km2 since the Tertiary, and finds that the Alxa Plateau was once an area with many rivers and lakes with a warm and humid climate. The relief reversion caused by neotectonic movement since "Qinghai-Tibet movement" is also analyzed.  相似文献