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一直以来,由Biot孔隙弹性动力方程得到的饱和土地下源Green函数都是u-w形式（u为固相介质位移,w为流相相对于固相的平均位移）。应用两相介质纵波解耦理论,得到了饱和土半空间地下点源荷载的u-P形式（P为孔压）Green函数频域解答;克服了u-w形式Green函数在边界元（BEM）积分时的增根影响。再由Hankel反演,结合Somigliana表象积分,完成BEM计算。并以计算结果分析了地下集中力作用时,饱和土位移、孔压、排水量等动力特性,这对地铁等交通工程、地震工程、土-结构动力相互作用（SSI）的响应计算都具有较重要应用价值。 相似文献
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岩石化学是研究各种地质过程的本质联系和演化规律的重要手段与方法.据国外统计,1841～1913年,全世界完成火成岩分析11024件,加拿大地质调查所1846～1954年分析了1300件,1954～64年分析了6200件,美国1966～68年平均每年分析2800件.随着我国地质科学的迅速发展,对岩石化学分析的要求与日俱增.本文着重讨论蚀变对岩石化学研究的影响.一要求与现状根据岩石学上的要求,在选择岩石化学资料时必须考虑:(1)岩石学的研究程度,样品的岩石名称、岩性及岩相划分、产 相似文献
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Any of iron-copper ore deposits, without exception, contains various associated components. The studies on the distribution and mode of occurrence of over 20 associated elements in 87 iron-copper ore deposits in a certain district in China have shown that the specificity of the associated element distribution is eontrolled by the type of the deposits, that there exists a close relation between ore.forming and associated elements, and that the formation conditions and type of ore deposits, and the geochemical properties of the elements are the decisive factors governing the migration and enrichment of the associated elements during minerogenetie process. 相似文献
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Based on a review of the available petrological and petrochemical data on magmarie rocks in a certain district in China, the average chemical composition of magmarie rocks has been calculated, and the frequenee distribution of elements in rocks,mineralization of rock bodies and regional geochemical characteristics have been discussed. In response to the temporal and. spatiai variations during the evolutionary process of magmatie activity, a systematic variation is obvious from this study in the chemical compositions of magmatie rocks, the frequence distribution patterns of elements, the concentration levels of various elements, the calc-alkaline index of the rocks as well as in the average atomic weight and average atomie valence. Particularly,different geochemical indicators have been observed for mineralized and barren rock bodies respectively. Crystallization-differentiation and postmagmatic metasomatism constitute the most important mechanisms controlling mineralization. 相似文献
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磁铁矿矿物化学、成因及演化的探讨 总被引：13，自引：0，他引：13
本文通过大量实际资料的研究,初步探讨了磁铁矿中主要元素的分布、共生组合、矿物化学类型及其演化。一、磁铁矿类型的划分本文采用的磁铁矿分析数据总数约3000个,主要是我们自己历年积累的资料和国内外有关书刊的资料。为便于研究对比,按产状及成因将磁铁矿划分为岩浆型(或岩浆熔离型)、火山岩型(或玢岩型)、接触交代热液型(简称接触交代型)、矽卡岩型、沉积变质型和副矿物型等六类。第一类有我国四川,陕西、河北和苏联哈萨克斯坦等地的岩浆熔离矿床;第二类有宁 相似文献
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钦州湾不同类型红树林土壤因子调查与分析 总被引：1，自引：0，他引：1
对钦州湾的红树林资源进行实地踏查后,选取中盐区光滩(CK1)和4个红树林类型、高盐区光滩(CK2)和2个红树林类型的土壤进行调查研究,测定土壤理化性状和养分等10个因子,并计算土壤肥力指数。结果表明:①不同类型的红树林土壤因子不同,只有高盐区3个样地的土壤pH值和容重没有显著差异,其他类型的各指标均存在显著差异;②与光滩相比,红树林能改变其生长的土壤理化性状,加重土壤盐渍化和酸化,有利于重金属的沉积,同时,也增加土壤有机质和养分含量,提高土壤肥力。 相似文献
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Based upon a fairly large body of data available on vanadium in rocks and.minerals from a certain district in China, distribution pattern of vanadium is given in igneous and terrestrial volcanic rocks. Geochemical behaviour and favorable conditions for mineralization of this element are also discussed during different geological processes. 相似文献
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