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41.
对柴达木盆地东部地区侏罗系大煤沟剖面、绿草山剖面进行了露头取样,并利用Rock-Eval生油岩评价仪、色谱—质谱仪、稳定同位素质谱仪等实验分析测试技术对样品进行了地球化学特征分析。实验结果表明,样品有机碳含量变化从0.07%到56.8%,有机质类型以Ш型有机质为主,少数为型有机质,极少数为型有机质,灰黑色油页岩及黑色炭质页岩是侏罗系中的优质烃源岩。检测样品C29甾烷异构化参数C29αββ/(αββ ααα)、C29ααα20S/(20S 20R)分布范围分别为0.25~0.35、0.06~0.34,处于未熟—低熟状态。侏罗系水体环境较浅,多为滨浅湖与沼泽环境,具有煤系烃源岩特点,局部为水体比较咸化的半深湖—深湖环境。  相似文献   
42.
薛步高 《地质论评》1993,39(5):450-458
云南省金及伴(共)生金矿,可划分10个成矿带(区),含7个成矿亚带(区),主要分布在大地构造单元的活动区及稳定区的边缘,多沿深大断裂两侧分布。伴(共)生金矿划分8大成因—工业类型,占储量比例大的为火山岩型、沉积变质型、沉积改造型,其中火山岩型、热液型、斑岩型、岩浆型,通过深入工作,往往有发展为独立金矿的可能、而沉积改造型一般只能综合回收利用。  相似文献   
43.
Based on the information of geology, geochemistry, geophysics and remote sensing, the GIS of multi-source information is used to evaluate Cu, W and Au mineral resources in Northern Qilian, China. As the GIS evaluation system works out in the thinking of geological prospecting, its functions include file management, graph edition, database maintenance, information inquiry and comprehensive spatial analysis as well as prospecting target prognosis. Accordingly, the GIS evaluation system can be used directly and conveniently for inquiry and analysis of visual graphs or images.  相似文献   
44.
Collagen of squid(Ommastrephes bartrami) skin was examined in the present study. Histology showed that collagen fiber in the skin was partially cross-linked with muscle fiber. Acid-solubilized collagen(ASC) and pepsin-solubilized collagen(PSC) were extracted from the skin and characterized. The results of amino acid composition and electrophoretic patterns revealed that ASC and PSC were both type Ⅰ collagen,containing α1 and α2 chains. FTIR(fourier transform infrared spectroscopy) investigations confirmed t...  相似文献   
45.
Three Cenozoic basins-the Qaidam basin, the Weihe graben-type basin and the North China plain-which are different in climatic conditions, geological settings and run-off types, are selected for the study. Based on an analysis of background information of the transect along the middle-latitude region, studies of groundwater dynamics, geochemistry, simulation of water circulation of the main elements as well as isotopic chronology, the information on global changes is collected, the formation of groundwater circulation systems and their evolution under stacked impacts of natural conditions and human activities are discussed, and a correlation is made between the evolutionary features of the above systems in these basins since 25 ka B.P. All these have laid a good foundation for further generalizing the evolutionary model of land water in northern China.  相似文献   
46.
Introduction Houhan Shu?ZHANG Heng Biography written by FAN Ye(AD398?AD445,South-North Dynasties)described about the response of ZHANG Heng’s Seismometer to Longxi earthquake as follows.“On one occasion a dragon dropped a ball without an earthquake being felt.All the scholars in the capital blamed this effect happening without any feelings of the earthquake.Several days later,a messenger arrived reporting that an earthquake really had taken place at Longxi.There-upon people all a…  相似文献   
47.
丁旭  赖欣  范广洲 《高原气象》2022,41(1):24-34
利用 197-2014年 GLDAS-CLM(Global Land Data Assimilation System-the Community Land Mod-el)地表参量数据集、中国区域逐日观测资料格点化数据集(CN05.1)和ERA-nterim大气环流再分析数据,研究青藏高原5月(春季)土壤湿度的异常变化...  相似文献   
48.
According to topography of Yemen,most areas and villages are located at obligated crest,toe of mountain and under cliffs.Therefore Al-Huwayshah consisting of Tawilah sandstone group is characterized by steep slope reach to 90° in some areas.This area is affected by strong tectonic movements and faults that occurred during the geological epochs.This effect enhances to find out fractures and joints as well as the rocks become brittle and ready to slide depending on the position of area.And there are some frac...  相似文献   
49.
About forty productive oil/gas fields hosted in volcanic reservoirs have been found since 1957 in fourteen basins of China. They can be simply subdivided into two groups, the east and the west. Reservoir volcanic rocks of the east group are predominantly composed of Late Jurassic to Early Cretaceous rhyolite and Tertiary basalt, preferred being considered as rift type volcanics developed in the circum-Pacific tectonic regime. Those of the west are Permo-Carboniferous intermediate/basic volcanic rocks, being island-arc type ones developed in paleo-Asian Ocean tectonic regime.  相似文献   
50.
The authors tested the percussion-extruding Down-the-hole (DTH)hammer bit with five different structures and mainly analyzed the drilling mechanism between conical bit and stepped bit. In addition, aiming at "the pile effect" in combination with the advantage' of stepped bit, we design a new cam spinning bit and test it outdoors. The result shows that using cam spinning bit can solve the problem of "the pile effect", which can also obtain higher drilling efficiency than using conical bit in high confining pressure strata. It is characterized by novel structure and high drilling speed as well as good guiding, and it is significant for improving efficiency in percussion-extruding drilling technique.  相似文献   
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