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141.
新疆乔尕山金矿床成矿流体来源研究 总被引:1,自引:1,他引:1
对乔尕山金矿床脆韧性剪切变质成矿作用阶段形成的受不同程度剪切的石英脉中流体包裹体气相成分分析表明,由糜棱岩化石英脉→初糜棱岩石英脉→石英脉糜棱岩,气相成分总量及主要组分H2O和CO2的含量均呈有规律的降低。两个主要成矿阶段形成的石英脉具有相似的H、O同位素组成,δ^18OH2O=5.25‰~9.54‰,δDH2O=-70.9‰,~-42.0‰,受剪切岩石中矿物中流体包裹体所代表的流体是韧性剪切金矿 相似文献
142.
路南石林喀斯特的形态特征及地质演化 总被引:1,自引:0,他引:1
石林喀期特是喀斯特地貌中的一种极端形式,主要由表面溶良发育,高达30 ̄50m的剑状石峰、石柱组成。同世界其他一些著名的剑状喀期特相比,路南石林喀斯特具有最为复杂的地质演化历史和最为多样的形态。研究表明:自2亿5千万年前早二叠世末期首次出现石牙以来,石林的发育经历了四大演化阶段;石林的形成是有利的地质、水文、气候条件综合作用的结果,而土下溶蚀是主要形成机理。剑状、峰状、塔状、蘑茹状及其他不规则状为石 相似文献
143.
Determination of Trace Elements in Twenty Six Chinese Geochemistry Reference Materials by Inductively Coupled Plasma-Mass Spectrometry 总被引:20,自引:0,他引:20
We report new data for thirty seven elements determined in twenty six Chinese geochemistry reference materials using inductively coupled plasma-mass spectrometry and a reliable and simple dissolution technique. One hundred milligrams of sample were digested with 1 ml of HF and 0.5 ml of HNO3 in PTFE-lined stainless steel bombs heated to 200 °C for 12 hours. Insoluble residues were dissolved using 6 ml of 40% v/v HNO3 heated to 140 C for 3 hours. Analytical calibration was accomplished using aqueous standard solutions. Rhodium was used as an internal standard to correct for matrix effects and instrument drift. Precisions were typically better than 5% RSD. Most of the data presented here agree well with the published certified values. For the elements Zr, Hf and most other trace elements, the measured values were less than 10% in error when compared to certified values. 相似文献
144.
145.
本文记述了采自山东淄博地区晚石炭世太原组双壳类化石15属28种,讨论了化石组合特征.在研究双壳类动物群的基础上,划分了3个动物群落,即:Acanthopecten群落、Palacolima群落和Aitartella群落,并对各群落的生态特征进行了系统研究. 相似文献
146.
论当前我国北西部铀矿勘查关键技术 总被引:1,自引:1,他引:1
本文提出当前我国北西部铀矿勘查两项关键技术──中国北西部寻找大型超大型可地浸砂岩铀矿勘查技术和找矿勘探过程中地浸可行性评价技术,并论述了技术内容和技术开发目标。两项关键技术的开发研究和落实对扩大我国铀矿资源有现实意义。 相似文献
147.
非等间距序列的灰色预测模型及其在岩石蠕变断裂中的应用 总被引:3,自引:1,他引:3
给出了非等间距序列的灰色预测模型,讨论了该模型的灰色预测平面和最优预测函数。最一将该模型应用于符合Kelvin模型的岩石材料的蠕变断裂研究,给出了应用实例,并验证了该方法的可行性。 相似文献
148.
在山东省德州市首次探明国内稀有含碘饮用用天然矿泉水--“中华碘泉”,研究表明,矿泉水是在新生代断陷盆地的构造背景和弱碱氧化的水文地球化学环境条件下,地下水与含水介南长期水-岩反应中经溶滤形成的,矿泉水水量丰富,水质优良,为含碘水苏打型矿泉水,但氟含量偏讥;为合理开发这一富足资源,可选用电渗析,倾析方法降低氟含量,并将其作为规模化含碘矿泉水生产的技术工艺。 相似文献
149.
The composition of the Earth 总被引:317,自引:0,他引:317
Compositional models of the Earth are critically dependent on three main sources of information: the seismic profile of the Earth and its interpretation, comparisons between primitive meteorites and the solar nebula composition, and chemical and petrological models of peridotite-basalt melting relationships. Whereas a family of compositional models for the Earth are permissible based on these methods, the model that is most consistent with the seismological and geodynamic structure of the Earth comprises an upper and lower mantle of similar composition, an Fe---Ni core having between 5% and 15% of a low-atomic-weight element, and a mantle which, when compared to CI carbonaceous chondrites, is depleted in Mg and Si relative to the refractory lithophile elements.The absolute and relative abundances of the refractory elements in carbonaceous, ordinary, and enstatite chondritic meteorites are compared. The bulk composition of an average CI carbonaceous chondrite is defined from previous compilations and from the refractory element compositions of different groups of chondrites. The absolute uncertainties in their refractory element compositions are evaluated by comparing ratios of these elements. These data are then used to evaluate existing models of the composition of the Silicate Earth.The systematic behavior of major and trace elements during differentiation of the mantle is used to constrain the Silicate Earth composition. Seemingly fertile peridotites have experienced a previous melting event that must be accounted for when developing these models. The approach taken here avoids unnecessary assumptions inherent in several existing models, and results in an internally consistent Silicate Earth composition having chondritic proportions of the refractory lithophile elements at 2.75 times that in CI carbonaceous chondrites. Element ratios in peridotites, komatiites, basalts and various crustal rocks are used to assess the abundances of both non-lithophile and non-refractory elements in the Silicate Earth. These data provide insights into the accretion processes of the Earth, the chemical evolution of the Earth's mantle, the effect of core formation, and indicate negligible exchange between the core and mantle throughout the geologic record (the last 3.5 Ga).The composition of the Earth's core is poorly constrained beyond its major constituents (i.e. an Fe---Ni alloy). Density contrasts between the inner and outer core boundary are used to suggest the presence ( 10 ± 5%) of a light element or a combination of elements (e.g., O, S, Si) in the outer core. The core is the dominant repository of siderophile elements in the Earth. The limits of our understanding of the core's composition (including the light-element component) depend on models of core formation and the class of chondritic meteorites we have chosen when constructing models of the bulk Earth's composition.The Earth has a bulk Fe/Al of 20 ± 2, established by assuming that the Earth's budget of Al is stored entirely within the Silicate Earth and Fe is partitioned between the Silicate Earth ( 14%) and the core ( 86%). Chondritic meteorites display a range of Fe/Al ratios, with many having a value close to 20. A comparison of the bulk composition of the Earth and chondritic meteorites reveals both similarities and differences, with the Earth being more strongly depleted in the more volatile elements. There is no group of meteorites that has a bulk composition matching that of the Earth's. 相似文献
150.