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Trace and RE element geochemistry and genesis have been studied with respect to ferromanganese nodules from the sediments of the Pacific, Atlantic and Indian oceans. 相似文献
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本文应用化学热力学的观点分析讨论了具有正磷酸盐、方解石和文石三种矿物成分的介壳生物化石的形成顺序.从理论上清楚地解释了在介壳生物的演化过程中,磷酸盐介壳形成在先,方解石介壳形成在次,文石介壳形成在后这一地质事实。在此基础上根据活度-pH图解,定性分析了具不同矿物组合的介壳生物化石所处地质时代的海水pH条件,指出元古代末磷酸盐介壳发育时,海水的pH可能接近于6,而古生代碳酸盐介壳广泛发育时,海水的pH可能己接近或超过6.45。 相似文献
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我国台湾浅滩海底沉积物稀土元素地球化学 总被引：12，自引：0，他引：12
REE geochemistry of sea-floor sediments from the Taiwan Shallow has been studied.∑ REE of 76 samples from the Taiwan Shallow was determined by chemical extraetion-spectrophotometry, of which 7 samples were analyzed for 15 rare earth elements by XRF. The analytical results show that ,∑ REE of the samples increases gradually with a decrease in grain size. The average REE contents are 60 ppm for coarse-grained sediments,82 ppm for medium-coarse-grained ones, 145 ppm for fine-grained ones, and 211 ppm for silt. The REE content of the samples is controlled mainly by the grain size and mineralogical composition of sediments. The ehondrite-normalized REE distribution patterns in sediments from the Taiwan Shallow are similar to those in granites in Fujian Province, China, which show a negative Eu anomaly and a positive Ce anomaly. The distribution curves are negative in slope. It is considered that based on REE geochemical characteristics, mineralogical composition and related oceanographic information, the Taiwan Shallow sediments seem to be largely residual deposits of ancient littoral facies from various types of continental rocks during Pleistocene glacial period. These sediments have also been reworked by modern sedimentatoion. 相似文献
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本文根据1983年采集样品系统地研究了冲绳海槽沉积物的化学成分,结果表明,冲绳海槽沉积物的主要化学成分为SiO_2,CaCO_3和Al_2O_3,尤其以CaCO_3含量较高而明显地区别于深海沉积物或陆架沉积物。从常量元素与微量元素之间的关系来看,冲绳海槽沉积物的绝大部分样品接近于陆壳物质,只有少数样品与洋壳物质相近。上述特征表明,冲绳海槽沉积物的物质来源除了生物沉积成因以外,在一定程度上仍以陆源碎屑沉积为主体,同时也有部分海底火山物质的加入。 相似文献
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本文通过对黄河中游地区马兰黄土的大面积野外实地考察，系统采样和室内分析测试，并采用质量加权平均的计算方法，给出了较为准确的中国黄土平均化学成分数据．中国黄土相对于下地壳和全地壳较富大离子半径的亲石元素而贫亲铁元素；与上部大陆地壳相比，中国黄土除相对较富Ｃａ．Ｂ而贫Ｎａ、Ｎｂ外，其余绝大多数化学元素的丰度均非常接近甚至几乎相等。由此表明。中国黄土确属典型的上部大陆地壳物质，它不仅为暴露的上部大陆地壳提供了一种理想的天然平均样品，而且中国黄土的平均化学成分完全可以作为上部大陆地壳化学成分的代表而加以应用。 相似文献
6.
吴明清 《矿物岩石地球化学通报》1997,(1)
老骥伏枥志在千里——贺郭承基教授八十华诞１９９７年１月郭承基教授届满八旬，也是他从事地学工作５７周年，我们在此表示衷心祝贺。郭老１９１７年１月２１日生，山西清徐人，著名的稀土、稀有元素矿物学和地球化学家，中国科学院院士，现任中国科学院地球化学研究所研... 相似文献
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Samples were collected f5rom the Selong-Xishan Permian/Triassic boundary strata,Nyalam County in southern Tibet and systematically analyzed for their rare-earth elements(REE) and trace elements such as U,Th,Sr,Ba,Sc,Ta,Hf,Rb,Cs,Co,Ni,Cr,As and others with emphasis put on the distribution patterns of rare-earth elements and the variation of trace element contents along the Permial/Triassic boundary section.On this basis a discussion will be made of the paleo-ocean depositional environment. 相似文献
8.
吴明清 《矿物岩石地球化学通报》1986,(1)
应日本学术振兴会的邀请,笔者陪同郭承基教授于1985年9月28日至10月25日对日本进行了为期28天的访问。我们先后考察了日本地质调查所、东京大学、京都大学、京都教育大学、奈良教育大学、大阪大学等单位,会见了增田彰正、藤井纪之、森本信男、山本俊夫、小泉光惠等五十多位日本学者,郭承基教授作了两场学术报告,与日本学者举行了多次座谈,交换了大量文字资料和图件。此外,还参观了一些大学和研究所的实验室,所到之处受到 相似文献
9.
南海玄武岩的某些地球化学特征 总被引：14，自引：1，他引：14
Petrochemistry,geochronology,trace and REE geochemistry have been studied of a few basalts from the South China Sea.The results show that the South China Sen basalts may be divided into two types;alkali basalts and tholeiites.The former is similar to common alkali basalts in petrochemistry,REE distribution pattern and trace element geochemistry,but the latter is similar to Hawaiian tholeiites,belonging to the transition type between alkali basalt and MORB(mid-oceanic rise basalt). 相似文献
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