排序方式： 共有29条查询结果，搜索用时 15 毫秒
21.
等离子体质谱法测定岩石中的锆、铪、铌、钽 总被引：8，自引：0，他引：8
本文建立了用HF、HNO3 在高压釜内溶解样品 ,准确测定花岗岩样品中Nb、Ta、Zr、Hf的ICP MS分析方法。分析结果与推荐值的偏差在 5 %以内。该方法具有简单、准确、测定元素多的特点。本文还对高压釜酸溶和碱熔方法进行了对比实验。 相似文献
22.
西藏南部中酸性岩中锆石铀-铅计时讨论 总被引：2，自引：0，他引：2
U-Pb isotopie geological ages were determined on more than 30 specimens of zircon,feldspar, sphene and apatite from the Kangdeee rock belt and its eastern Bome-Zayu areas in Xizang (Tibet). The study of common lead derivation and its mode of occurrence in zircon indicates that large amounts of common lead occur as sulphide-faeies minerals er exist in the cyrstal lattice of zircon, rather than introduced by contamination during analytical procedure. Described in this paper is the validity of subtracting zircon-containing common lead from the isotopie components of syngenetic galena, consequently leading te the conelusion that intermediate-acid rocks in the studied region are brought forth by late Yenshanian (120--80 m. y.) movement, It is suggested from the quantity of common lead and the difference in lead isotopic composition that the western segment of the Kangdese belt and its eastern Beme-Zayu areas may have two different material sources. 相似文献
23.
基于国外大量硼同位素示踪的地热研究实例,在先期建立的MC-ICP-MS测定水中硼同位素分析方法基础上,以羊八井地热田为研究对象,进行了热田地热流体的硼同位素地球化学初步研究。研究表明,羊八井地热田区热储流体的硼同位素值为 -10.5‰～-9.1‰,为非海相来源; 结合区域地质特征,研究认为热储内的硼组分来源于蚀变花岗岩围岩,并且蚀变花岗岩的硼同位素特征可能与深层地热流体相似。研究表明羊八井浅层热储内硼元素的地球化学行为并非完全是保守元素,存在着一定的硼同位素分馏。在端元硼同位素特征差异较小的羊八井热田,为硼同位素二元混合模型示踪水体混合过程带来了相当的复杂性。本文从热田开采过程与采样时间、水-岩相互作用、气-液相分离以及结垢过程等方面分析了浅层热储内引起硼同位素分馏的可能因素,其中从整体来看,气-液相分离过程的影响相对较大;而在个别井位水-岩相互作用与结垢的影响可能相对较为显著。 相似文献
24.
1987年以来,先后做了4条横穿昆仑山的综合路线地质调查。它们是:中-巴公路沿线;新-藏公路沿线;于田县普鲁村-苏巴什-硫磺达坂路线;青海茫崖镇-祁曼塔格路线。在西昆仑山北部的调查区内,都有钙-碱性的深成岩体出露。通过对这些岩体系统地做U-Pb、Ar-Ar及Rb-Sr定年研究,发现它们具有早古生代年龄(384-480Ma),延伸上千公里,形成于活动大陆边缘或碰撞后的构造环境,常与属于蛇绿岩套的组分相伴生。这充分说明在青藏高原内部存在一条新发现的缝合带。 相似文献
25.
26.
１９８７年以来，先后做了４条横穿昆仑山的综合路线地质调查。它们是：中－巴公路沿线；新－藏公路沿线；于田县普鲁村－苏巴什－硫磺达坂路线；青海茫崖镇－祁曼塔格路线。在西昆仑山北部的调查区内，都有钙－碱性的深成岩体出露。通过对这些岩体系统地做Ｕ－Ｐｂ、Ａｒ－Ａｒ及Ｒｂ－Ｓｒ定年研究，发现它们具有早古生代年龄（３８４—４８０Ｍａ），延伸上千公里，形成于活动大陆边缘或碰撞后的构造环境，常与属于蛇绿岩套的组分相伴生。这充分说明在青藏高原内部存在一条新发现的缝合带。 相似文献
27.
从中酸性的岩浆活动论西藏高原地壳运动特征 总被引：3，自引：0，他引：3
In view of their distinct NWW trending and their decreasing geological age from north to south, intermediate-acid magmatic rocks in the southern part of Xizang can be divided into three petrographical belts in general: (1) the Kangdese belt (120--10 m.y.). The major part of the belt is mainly composed of diorite, granodiorite, etc.,more intermediate in chemical composition and ranges from 120---70 m. y. in age; (2)the Lhangoi Kangri belt (30 m. y.) ; and (8) the Himalaya belt (20--10 m. y.). From their intruding features, spatial-temporal consistency, intruding scale, petrological characters and chemical Composition, it is suggested that these three petrographical belts secm to be closely related to plate underthrust and collision. It may be concluded that the major part of the Kangdese belt is resulted from the underthrust of the Indian Ocean Plate towards the Eurasian Continental Plate while the Lhagoi Kangri belt and the Himalaya belt are the results:of collision of the Indian sub-Continental Plate overlying the .Indian Plate with the Eurasian Continental Plate. 相似文献
28.
29.