长江中下游及邻区区域铅同位素组成背景及其应用   总被引：6，自引：0，他引：6  

马振东  单光祥 《地质学报》1996,70(4):324-334

本文系统地研究了长江中下游及邻区区域各类地质体铅同位素组成背景。研究表明：区域各类地质体铅同位素组成特征是受原始地幔的不均一性、壳幔交换的动力学过程、层圈铀、钍、铅丰度及作用发生的时间等诸因素控制，为此，通过区域铅同位素背景的研究可以为地球化学分区、示踪物质来源及区域成矿预测提供有意义的信息。  相似文献   

双沟蛇绿岩中地幔交代作用的质子微探针研究   总被引：3，自引：0，他引：3  

陈友红  张旗 《岩矿测试》1996,15(3):168-172

采用空间分辨率高和高灵敏度的质子微探针和微束ＰＩＸＥ技术，测定地幔流体结晶后各组成矿物的微量元素组成及其在不同矿物内的分布状况。对云南双沟蛇绿岩中存在的地幔交代作用进行的研究结果表明，由地幔流体结晶而成的矿物（单斜辉石、尖晶石、石榴石、绿泥石），其微量元素组成与分布特征受地幔交代作用过程的控制。这对于进一步探讨双沟地幔交代作用过程中微量元素的地球化学行为很有意义  相似文献   

Geochemistry of the Rare Earth Elements in Natural Terrestrial Waters：A Review of What Is Currently Knows   总被引：3，自引：0，他引：3  

KEVIN  H  JOHANNESSON ZHOUXIAOPING 《中国地球化学学报》1997,16(1):20-42

The range of observed chemical compositions of natural terrestrial waters varies greatly especially when compared to the essentially constant global composition of the oceans.The concentrations of the REEs in natural terrestrial waters also exhibit more variation than what was reported in seawater,In terrestrial waters ,pH values span the range from acid up to alkaline,In addition,terrestrial waters can range from very dilute waters through to highly concentrated brines.The REE concentrations and their behavior in natural terrestrial waters reflect these compositional ranges,Chemical weathering of rocks represents the source of the REEs to natural terrestrial waters and ,consequently,the REE signature of rocks can impart their REE signature to associated waters,In addition,Because of the typical low solubilities of the REEs both surface and solution complexation can be important in fractionating REEs in aqueous solution.Both of these processes are important in all natural terrestrial waters,however,their relative importance varies as a function of the overall solution composition,In alkaline waters,for example,Solution complexation of the REEs with carbonate ions appears to control their aqueous distributions whereas in acid waters,the REE signature of the labile fraction of the REEs is readily leached from the rocks.In circumneutral pH waters,both processes appear to be important and their relative significance has not yet been determined.  相似文献   

鄂尔多斯盆地东胜煤田高岭土的物质组成及质量特征     

黄焱球  程守田 《华南地质与矿产》1997,(2):6-10

东胜煤田延安组含煤岩系砂岩型高岭土矿石属杂砂岩，基质含量高，矿物组成简单，石英和高岭石分别构成砂岩的碎屑和基质，其它组分含量低碎屑与粘土在粒度和物性上的差异，使两者易于分离。精选漂白的高岭土纯工高，细料组分个体户量和自然白度均较高，是一种优良高岭土。分选出的石英等尾砂ＳｉＯ２含量大于９０％，可综合利用。  相似文献   

中国东部上地壳化学组成   总被引：10，自引：0，他引：10  

鄢明才  迟清华  顾铁新  王春书 《中国科学D辑》1997,(3)

在中国东部(东经105°以东)约计330万km~2系统采集了28253个岩石样品,组合成2718件分析样,选用了15种可靠的分析方法,以国家一级标准物质监控分析质量,提出了76种化学元素在中国东部出露地壳、沉积盖层、出露基底和上地壳的平均化学组成.  相似文献   

古里雅冰帽8米浅冰芯的化学成分组成特征及其来源   总被引：10，自引：3，他引：10  

李月芳  姚檀栋 《冰川冻土》1997,19(2):173-179

对古里雅冰帽８ｍ浅冰芯的８０个雪冰样品化学分析结果表明，化学成分主要来自陆源物质，陆源冰芯样品叶弱碱性，明显不同于一般的大气降水及南北极冰雪样品。  相似文献   

东秦岭造山带花岗岩类长石铅同位素组成及其构造学意义   总被引：10，自引：2，他引：10       下载免费PDF全文

张宏飞  张本仁 《地质学报》1997,71(2):142-149

本文对东秦岭造山带内２７个花岗岩类央体４８件长石样品进行了铅同位素成分的测定，结果表明，本区的南秦岭不同时代花岗岩类以贫铀铅和钍铅为特征，具有明显的铅同位素块体效应，反映它们属地同一个铅同位素构造－地球化学省；而本区的北秦岭区岗岩类从晚元古代到早古生长，长石铅同位素组成以富铀铅和钍铅的为特征，但从晚古生长开始，花岗岩类长石铅同位素组成明显发生变化，以贫铀铅和钍铅为特征，反映晚古生长及其后形成花岗质  相似文献   

Isotopic Characteristics and Key Factors Favoring the Formation of Fuwan Super-large Silver Deposit in Guangdong Province     

梁华英  喻亨祥夏萍王秀璋  程景平 《中国地球化学学报》2004,23(4):293-300

Rb-Sr isochron age of fluid inclusions in quartz from the Fuwan super-large silver deposit is 68 - 6 Ma, the silver deposit is characterized by high μ values (10.67 - 10.95 ), which are much higher than those of the ore-hosted Paleozoic strata and are close to those of ores hosted in the Proterozoic metamorphic basement in western Guangdong Province. Based on the Pb isotopic characteristics, coupled with much high background silver contents (200-1000ng/g) in the Proterozoic basement and relatively low silver contents in the Paleozoic strata in the region of the Sanshui Basin, it is concluded that the ore-forming material of the super-large silver deposit came mainly from the old basement. The super-large silver deposit related genetically to the intense volcanic activities during the Upper Cretaceous to Eogene. The formation of the Fuwan super-large silver deposit is controlled by the following favorable geological conditions : ( 1 ) The intersection of deep faults and contemporaneous faults at the margin of the Sanshui Basin led to the formation of an excellent structure as passageway for ore fluids; (2) The special ore-hosted rock association forms a ore gathering-trap structure that favors the precipitation of ore; (3) The silver-rich old basement, multi-stage mineralization and multi-episode volcanic activities which constitute a geothermal convection system.  相似文献   

东濮凹陷白庙地区天然气及凝析油地球化学特征及成因   总被引：1，自引：0，他引：1  

罗小平  沈忠民  彭渤莹  王又杰  林壬子 《沉积学报》2004,22(Z1):50-55

白庙构造是东濮凹陷南部地区的一个含凝析油的富气构造.在研究油藏基本地质特征的基础上,应用多种地球化学手段研究了气藏中天然气组分、甲烷同位素及惰性气体同位素变化规律、凝析油族组成、饱和烃色谱、色质生物标志物特征,进行了油气源分析,探讨了气藏的形成时间与次序,白庙气藏具有多源、多期、复合成藏的特点.  相似文献   

页岩、煤、沥青和原油的生气实验研究   总被引：4，自引：0，他引：4  

王云鹏  耿安松  刘德汉  熊永强  申家贵 《沉积学报》2004,22(Z1):106-109,117

选取了有代表性的页岩(海相页岩与油页岩)、煤、沥青与原油样品进行了真空封闭体系生气模拟实验,研究了不同生气母质的生气高峰阶段及其在不同热演化阶段的气产率及气体组成 ,综合探讨了不同生气母质的生气机制与生气规律及母质类型、热演化程度等对气产率及所生天然气组成的影响.为有效气源岩的判识提供了实验依据.  相似文献