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81.
辽宁后仙峪硼矿区古元古代电气石岩: 锆石特征及SHRIMP定年 总被引:4,自引:0,他引:4
为了确定辽东硼矿含硼岩系中电气石岩的形成时代, 对后仙峪硼矿区电气石岩首次进行了锆石SHRIMP U-Pb年龄测定.阴极发光图像显示, 锆石具核-边结构, 锆石核部多具振荡环带, 为高Th/U值的岩浆碎屑锆石; 锆石边部无明显结构变化, 为变质成因.岩浆碎屑锆石和变质锆石的年龄分别为2 171~2 175 Ma和1 894~1 906 Ma.结合野外地质和岩相学研究, 认为后仙峪硼矿区电气石岩原岩为古元古代克拉通裂谷环境中源于地壳再循环组分混染的亏损地幔的中酸性岩浆活动引发海底喷流作用的产物, 其原岩形成时代为古元古代中期(2 171~2 175 Ma), 并在稍后(1 894~1 906 Ma)遭受变质作用叠加改造. 相似文献
82.
通用地质坐标系(Gerneral geological coordinate system)是能计算地学要素中点、线、面几何关系的计算方法,其中提出的地学要素标准化方案在基于GIS的地质图件编绘中能起到很好的作用。通过岩层真厚度计算、用钻孔资料确定地下岩层产状、弯曲钻孔计算、基于GIS的地质图图切剖面中真视倾角计算等实例以及通用地质坐标系中提出的标准化方案在图件编绘中已显示出优点,说明通用地质坐标系具有简便实用性、先进性与系统化的特点,其在地质领域中应用可以发挥很大的作用,建议推广应用。 相似文献
83.
针对我国油气资源数据相对多源、异构、分散的现状,根据OLAP的实际需求,采用MVC模式作为系统架构模式,实现了国家油气资源数据库数据提取、转换和加载(ETL)系统。阐述了系统所采用的基于面向对象体系结构(SOA)的5层结构模型,使用ODBC和XML技术实现数据库连接的动态映射,应用Oracle DB解决了多媒体数据处理等关键问题。 相似文献
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86.
Relationships Between the North China Plate and the Tarim Plate 总被引:3,自引:0,他引:3
Wang Tingyin Wang Jinrong Liu Jinkun D epartment of Geology Lanzhou U niversity Lanzhou GansuWang Shizheng Ningxia Bureau of Geology Mineral Resources Yinchuan Ningxiaand Wu Jiahong Shenyang Institute of Geology Mineral Resources Shenyang Liaoning 《《地质学报》英文版》1994,68(2)
The relationships and boundary between the North China and Tarim plates have been unclear for a long time ; however, the two plates occupy a prominent position in the formation and evolution of the continental lithosphere of China. It is proposed that the Engger Us ophiolitic melange zone discovered recently north of Alaxa is a typical suture between the two plates. The ophiolitic melange zone is composed mainly of a mixture of fragments of ancient oceanic crust and sedimentary rocks of active and passive continental margins. The melange may be divided into tectonic inclusions and matrix. The suture extends northeastwards into the Republic of Mongolia and probably westwards to meet the Altun fault. With the Engger Us ophiolitic melange zone as the boundary the Alaxa area may be divided into two parts: the northern part (AN ) belongs to the Tarim plate, while the southern part (AS) the North China plate. Geological evidence shows that the two plates were amalgamated in the Late Permian or a bit later. 相似文献
87.
Ming FENG Li LIU Yu ZHANG Xigang REN Chengke XU 《东北亚地学研究》2006,9(2):242-245
The natural balance conditions will be disturbed and produce a series of problems when mineral deposit has mined.This paper has researched the engineering rock masses have been researched in this study,structural planes,the distribution characteristics of tectonic geological factors and the stability of engineering structures according to the theory and research methods of rock mechanics,it will provide the engineering geological evidence for mining area exploited,meanwhile pledge the safety production.Shanmen silver deposit is a large epithermal deposit,it is controlled by NE to NNE strike faults.The stability of rock mass is acted on the tectonic movement and hot metalliferous brine in long-term.Especially,strength of rock mass becomes softened,muddy and loosed under the action of water,so the lower stability of rock mass is,the easier it can take place for harm of disaster threatening production safe of mining.For this reason,it is very important that drawing up a plan to lower harm for mine and protect. 相似文献
88.
HUANG Zhiquan WANG Gangcheng ZHANG Guojun.College of Construction Engineering Jilin University Changchun China.Liaoning Electric Power Survey Design Institute Shenyang China 《东北亚地学研究》2009,12(2):112-116
Clogging effect, as a new concept in geological engineering, is a phenomenon of permeability decreasing under seeping in reservoir dam foundation of the alluvial and diluvial deposits with deep and thick layer, coarse particle and high permeability in mountains-gully rivers of Tibetan Plateau. A clogging infiltration instrument has been designed successfully and a series of simulation tests have been done. Based on large amounts of data, it is confirmed that the existence of the clogging effect and the law of infiltration clogging is found out. Three indexes are proposed such as "optimal size of particle", "optimal size range of particle" and "characteristic pore", which are closely related with effect of infiltration clogging. The concept and results can offer a new idea to solve problems on anti-seepage of dam foundation in mountains-gully rivers environment and to study artificial clogging, meanwhile supplement of the concept of seepage deformation. 相似文献
89.
本文从储层的岩性、成岩作用、孔隙类型及粘土矿物对孔隙结构的影响等方面对辽河坳陷曙光油田古近系沙河街组大凌河储层的孔隙结构特征进行了分析,揭示了该储层的微观非均质性和对开发效果的影响。研究表明该油层储集层成熟度低。大凌河储层的上油组岩石为长石质岩屑杂砂岩,下油组岩石为岩屑质长石砂岩。孔隙类型以粒间孔为主,少量溶蚀孔。孔隙结构以粗孔中喉型居多,其次为中孔细喉型和细孔细喉型。粘土矿物包括蒙脱石、伊利石、高岭石,其中蒙脱石含量最高,尤其是下油组。在油田开发时,为防止过度伤害孔隙结构、破坏储层,针对上下油组存在的非均质性,应制定不同的开采方案,控制注采液在油层中的流速,注入蒸汽的PH值不要高于9,同时在蒸汽水中加入适量的钾离子。 相似文献
90.
YOU Hailu JI QiangInstitute of Geology Chinese Academy of Geological Sciences Baiwanzhuang Roa Beijing E-mail: hyou@sas.upenn.eduLI Jinglu LI Yinxian Liaoning Paleontological Museum Beipiao Liaoning 《《地质学报》英文版》2003,77(2)
A new hadrosauroid dinosaur, Shuangmiaosaurus gilmorei gen. et sp. nov., is described based on a complete left maxilla with articulated premaxilla and lacrimal fragments, and a complete left dentary from the mid-Cretaceous Sunjiawan Formation of Beipiao, Liaoning, northeastern China. Cladistic analysis shows that Shuangmiaosaurus is a basal hadrosauroid, and comprises the sister taxon to Hadrosauridae. In both Shuangmiaosaurus and Hadrosauridae, the maxilla-jugal suture is butt-jointed, rather than finger-in-recess articulation as in other basal hadrosauroids. However, Shuangmiaosaurus does not possess such hadrosaurid synapomorphies as the diamond-shaped maxillary crowns with reduced primary ridges and reduced marginal denticles. 相似文献