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991.
国家卫星气象中心气象卫星资料存档系统 总被引:5,自引:4,他引:5
论述了国家卫星气象中心的气象卫星资料存档系统构成、存储数据的编目组织、应用软件的逻辑关联结构、层次框架结构及组织结构,介绍了应用软件主要功能和流程图,对存档系统建设中的经验进行了总结。 相似文献
992.
马元铅锌矿床是四川盆地北缘重要的铅锌矿床之一,赋矿地层为震旦系灯影组,野外可见大量的沥青与铅锌矿共生/伴生,镜下见早期沥青与闪锌矿、方铅矿共生,沥青的生物标志物与郭家坝组烃源岩极为相似。物质来源方面,铅锌成矿主要的物质来源和两期油气成藏的物质来源均为下寒武统郭家坝组;时间关系方面,铅锌成矿的共生矿物Rb-Sr同位素等时线年龄为(486.7±3.1)Ma,仅可能与第一期古油藏形成、破坏有关。闪锌矿和重晶石包裹体中含有CH4和少量H2S、沥青,表明铅锌成矿流体中富含有古油藏裂解产物。生烃、排烃、初次运移萃取出"双源层"中的铅锌元素,第一期古油藏裂解和短暂TSR作用产生的还原性硫为铅锌络合物沉淀提供了物质基础,第一期古油藏最终完全破坏残留下早期沥青。 相似文献
993.
The southern Lhasa Terrane is famous for its huge magmatic belt which records the magmatism during Mesozoic and Cenozoic. Although the Mesozoic continental-margin setting in the southern Lhasa Terrane has been identified,details of this tectonic setting and the evolution history during the Late Cretaceous remain unclear. To further constrain these issues,we present zircon LA-ICP-MS U-Pb,Hf isotopic and geochemical data of the Gongbari dacites(of the Sangri Group) which intruded by Paleocene granodiorites from the eastern part of the southern Lhasa Terrane,Tibet. New age data indicate that the dacites were generated at ~95.4 Ma,which suggests the Sangri Group volcanism may last to Late Cretaceous. The Gongbari dacites are characterized by high Sr(428–758 ppm) contents,low concentration of heavy rare earth elements and Y(e.g. Yb=0.78–1.14 ppm; Y=8.85–11.4 ppm) with high Sr/Y(41.91–67.59) and La/Yb(22.64–30.64) ratios,similar to those of adakite. The rocks are calc-alkaline,metaluminous,enriched in LILEs,depleted in HFSEs,and have positive εHf(t) values(+7.7 to +11.6). The Gongbari dacites were probably produced by partial melting of young and hot subducted Neo-Tethyan oceanic crust under amphibolite to garnet amphibolite-facies conditions. Though the Gangdese Mountains may have formed before Indo-Asian collision,the southern margin of Lhasa Terrane might not go through obviously crustal thickening during the northward subduction of NeoTethyan oceanic lithosphere. 相似文献
994.
Yunliang YU Shixiang LIU Narenna WU Xudong ZHANG 《东北亚地学研究》2007,10(1):59-64
The Vision Earth System is a interactive system by employing B/S model.The system has the function of query display and mutually displays relevant geologic information,integrating image information of one outcrop and realizing 3D geologic visualization.In this system,the basis is effective store,transmitting,display and quick query of enormous images and their properties data.From Java technology,this essay researches the elementary realization of Vision Earth System by adopting store formality of enormous images database,quick display image of website and quick image storage method. 相似文献
995.
The geodynamic setting of the Bikou volcanic group is a critical question to trace the Precambrain tectonic framework and evolution for the Yangtze plate. This study has suggested that the Bikou volcanic group is composed of several residual oceanic crust units MORB (mid-ocean ridge basalt), Alk-OIB (alkaline ocean island basalt) and Th-OIB (tholeiitic ocean island basalt) as well as subduction-related volcanic rocks. According to field observation, those distinct rocks occurred collectively in form of tectonic contact, implying that the Bikou volcanic group was an ophiolitic mélange. Coupled with geochronological data, a perished oceanic basin at the northern margin of the Yangtze block during Neoproterozoic was tested by this ophiolitic mélange. Meanwhile, the isogeochemical data suggest that the ocean occurred in the Southern Hemisphere identical to Indian, South Atlantic and South Pacific oceans in terms of their Dupal anomalies, and the original source of the rocks could be probably mixing by EMⅠand EMⅡ component caused by dehydration melting of subducting oceanic crust during subduction process. On the basis of geochemical characteristics of the studied rocks, the Bikou volcanic group could imply that a partial breakup event occurred in the northern margin of Yangtze plate during the Neoproterozoic era. 相似文献
996.
强制海退体系域由于可发育优质的储集层而备受石油地质学者关注,但关于强制海退体系域中烃源岩的研究仍然十分缺乏。根据岩性录井、测井曲线和地球化学分析数据,以尼日尔Termit盆地为例探讨强制海退体系域中烃了源岩的类型及其识别特征和地球化学特征,并通过改进的ΔlogR方法建立烃源岩总有机碳(TOC)含量测井预测模型,初步分析了不同类型烃源岩的发育特征和质量差异。结果表明:强制海退体系域中可以发育煤/炭质泥岩、滨岸泥岩、三角洲泥岩和滨外陆棚泥岩4种烃源岩,其中滨外陆棚泥岩发育于强制海退体系域的底部,而煤/炭质泥岩以薄层状伴生于盆地边缘附近滨岸沼泽相和三角洲相。基础地球化学数据表明滨岸泥岩主要为Ⅱ2型干酪根的好-极好烃源岩,三角洲泥岩为非均质性强烈的差-好烃源岩,而滨外陆棚泥岩整体为Ⅲ型干酪根的差-中等烃源岩。应用lgR-Δt交会图求取ΔlogR值,建立TOC测井预测计算模型,计算了其他井的TOC预测曲线,结果表明Termit盆地强制海退体系域中的泥岩基本为好-极好烃源岩,不同构造区块中差别不大,其中滨岸泥岩为主要的烃源岩类型,累计厚度大且生烃潜力高。从强制海退体系域的演化过程及Termit盆地实例研究来看,强制海退体系域中在一定条件下可以发育优质烃源岩,滨岸泥岩可能是其主要的烃源岩类型。 相似文献
997.
998.
黔西玄武岩铂族元素赋存状态及地质意义 总被引:2,自引:1,他引:2
在地球化学系统中,元素的亲合性是制约元素地球化学行为的基本属性,而赋存状态则反映元素质的属性.对黔西基性玄武岩原岩与流体包体中Pt、Pd的赋存状态进行研究,结果说明了利用元素亲合性对指导其赋存状态查定的重要性,同时表明了研究该地区玄武岩中同生流体包体中铂族元素对重演古流体中元素迁移与富集具有重要的理论与实际意义. 相似文献
999.
U-Pb Zircon Age,Geochemical, and Sr-Nd-Pb Isotopic Constraints on the Age and Origin of Mafic Dykes from Eastern Shandong Province,Eastern China 总被引:1,自引:0,他引:1
LIU Shen HU Ruizhong FENG Caixi GAO Shan FENG Guangying LAI Shaocong QI Youqiang Ian M. COULSON YANG Yuhong YANG Chaogui and TANG Liang 《《地质学报》英文版》2013,87(4):1045-1057
U-Pb zircon age, geochemical, and Sr-Nd-Pb isotopic data of mafic dykes from eastern Shandong Province, eastern China is reported herein. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb zircon analyses of two samples from the investigated mafic dykes yield consistent ages ranging from 121.9 Ma ± 0.47 Ma to 122.9 Ma ± 0.61 Ma. The mafic dykes are characterized by high (87Sr/86Sr) i ranging from 0.7087 to 0.7089, low εNd(t) values ranging from -16.9 to -17.8, 206Pb/204Pb = 17.15 to 17.17, 207Pb/204Pb = 15.45 to 15.47, and 208Pb/204Pb = 37.59 to 37.68. Results from the current study suggest that the mafic dykes are derived from partial melting of ancient lithospheric mantle that was variably hybridized by melts derived from foundered lower crustal eclogite. The mafic dykes may have been generated through subsequent insignificant crystal fractionation and very minor crustal contamination during magma ascent. Combined with previous studies, the current findings provide new evidence that the intense lithospheric thinning beneath the eastern Shandong Province of eastern China occurred at ~120 Ma, and that this condition was caused by the removal of the lower lithosphere (mantle and lower crust). 相似文献
1000.
对张广才岭南部一面坡花岗岩的地质学、岩石学、地球化学及锆石U-Pb年龄研究表明,岩石富硅富铝,属于过铝质岩石(A/CNK=1.04~1.07),全碱(K2O+Na2O)含量为8.24%~8.85%,K2O/Na2O值为1.58~1.68,属于高钾钙碱性系列I型花岗岩。岩石富集LREE、Rb、Th、U、K,相对亏损Nb、Ta、P、Ti,具有明显的Eu负异常,LA-ICP-MS锆石206Pb/238U年龄加权平均值为211Ma±4Ma(MSWD=1.4, 2σ),代表了花岗岩的结晶年龄。岩石具有相对亏损的锆石Hf同位素组成(εHf(t)=+1.75~ +13.81),TDM2为367~1136Ma。结合区域构造环境分析,认为一面坡晚三叠世花岗岩属于I型花岗岩,可能形成于后碰撞伸展构造环境,是岩石圈伸展阶段新增生下地壳物质发生部分熔融的产物。 相似文献