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A total of 21 elements, Si, Al, K, Na, Ca, Mg, Fe, Mn, Ti, P, Cu, Co, Ni, Zn, Pb, Cr, Rb, Sr Ba, Cd and Corg(organic carbon), was determined in the trough. Average contents of most elements were found to be higher in the trough bottom than in the western and eastern slopes. We call these elements the indicator elements because of their "transition" property. This is in keeping with the "intermediate" geographical position of the trough where the continental crust turns to oceanic crust.Though the authigenic fraction of some elements here increases, the detrital fraction .of most elements is still dominant, indicating that the influences of terrigenous and volcanic detrital materials on the trough sediments are still dominant.The abundant biogenous component in the trough is characterized by the increase of Ca, Sr and Corg contents. Ca existes mainly in the form of CaCo3 that is mostly found in various shells. Sr often easily replaces Ca within the shells.A belt-shaped distribution pattern of elements wa 相似文献
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Investigations and studies for years all demonstrated that there is a patch of fine-grained mud in the central area of the South Yellow Sea. However, scientists have different opinions on its material source, genesis, and sedimentation intensity. Some believe that the materials come from the Huanghe River, some think that the mud area represents the depocentre of the South Yellow Sea, and some consider it as "relict mud ". The authors ' geochemical study reveals that the mud is multi-sourced, yet the material supply is not ample, and that a little amount of fine-grained suspended materials deposited slowly under the dynamic action of a cyclonic gyre formed the modern muddy sediment, which is named "multi-source modern mud ". 相似文献
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为了促进大陆金矿地质的研究,查明现代海洋沉积物中金的丰度,无疑有所裨益,为此,本文首次报道了中国海底沉积物中金的丰度。 相似文献
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自从震旦系这一地质名词建立以来,各国学者在国外虽有相当地层的发现,但是由于国际地层表中没有一个统一的与之相应的术语,以致在不同的国家,甚至在同一个国家的不同地区就出现了不同的名称。特别是关于其地质时代问题,各家的意见更是众说纷 相似文献
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一、问题的提出山西式铁矿与G层铝土矿,早已载入了我国地质文献。但是对其成因和时代,以往还没有人作过专门性的详细讨论。近两年来,虽然已有人作了初步的探讨,可是还没有一个完满的答案。1956年夏,笔者到山西太原收集毕业论文的资料 相似文献
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中国大陆架海底沉积物中的稀土元素 总被引:30,自引:2,他引:30
选择渤海、黄海、东海和南海有代表性的大陆架沉积物样品,利用X射张荧光光谱法测定了15个稀土元素。中国大陆架沉积物稀土元素的丰度为156ppm,相对接近于中国黄土和花岗岩的丰度,而与太平洋沉积物的丰度相差较远,具有明显的“亲陆性”。稀土的配分模式旦显著的负斜率,属陆壳稀土的典型特征。稀土含量受沉积物粒度控制。实验表明稀土主要以类质同像存在于粘土矿物之晶体构造中。根据数理统计,稀土与亲陆源粘土矿物的元素为一类,彼此呈正相关;与亲海洋生物的元素为负相关。事实说明中国大陆岩石的风化和搬运,是中国海大陆架沉积物中稀土的主要物质来源。 相似文献
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利用数字地震仪、地质脉冲仪和3.5kH_Z真浅层剖面仪测量结果显示:南黄海地层可分为三个大层组,即第四系、上第三系和下第三系(或第三系以前的地层)。它们分别沉积在南、北两个沉积中心中,这两个沉积中心始终控制着盆地的沉积。在盆地发展过程中,西部大陆的物质一直是盆地沉积的主要物质来源。第四纪时,黄河已经显示了它对南黄海影响的主导地位。无论是第三纪还是第四纪沉积物均以陆相为主。第四纪的地质历史是复杂多变的,至少有两次以上的成陆过程。 相似文献