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401.
东准库布苏南岩体岩石化学特征及其地质意义 总被引:5,自引:3,他引:2
新疆东准噶尔卡拉麦里地区库布苏南岩体以花岗闪长岩为主,岩石具似斑状结构和块状构造.岩石化学研究表明,岩体具富SiO2 (64.24%~67.75%)、低Al2O3 (16.06%~22.00%)、富Na2O K2O (7.03%~7. 50%)特征,且Na2O>K2O,标准矿物中出现刚玉分子,属于准铝质高钾钙碱性Ⅰ型花岗岩类型.较低的DI(69.49~76.62)、FL(64.32~71.56)和MF(69.58~76.00),表明岩体具有壳-幔混合作用的特征.结合东准噶尔卡拉麦里地区晚古生代构造-岩浆演化过程分析,岩体形成于卡拉麦里造山带的大陆主碰撞后初始拉张阶段[(300±10) Ma],属后碰撞花岗岩,它是幔源岩浆在壳下和壳内不同深度上发生垫托,壳幔物质发生不同程度的分熔、混合和交换的产物. 相似文献
402.
403.
通过对西湖茶园的植物和土壤样品进行一系列的调查,以着力寻找茶叶的铅污染源。利用铅同位素技术对西湖茶园的土壤、茶叶和城区的燃煤、大气气溶胶、汽车尾气进行铅同位素示踪研究。研究表明,茶园土壤铅物质的可溶相具同源性和残查态偏于多源性。清洗后的茶叶铅含量显著降低,但其同位素组成不发生明显改变,显示出茶叶中的铅与叶面空气沉降物中的铅同源。不同介质铅同位素对比值平均值呈现表土、大气(气溶胶)、煤的w(206Pb)/w(207Pb)与茶叶趋于相近,汽油低之;表土、大气(气溶胶)、汽油的w(208Pb)/〔w(206Pb)+w(207Pb)〕与茶叶趋于相近,煤略高之。不同区域茶叶铅物质具同源性,与种植的农业地质背景无关。在煤燃烧、气化过程中,Pb进入大气,通过大气沉降或被茶树吸收或附着在茶叶叶面;汽车尾气的排放是茶树铅污染的重要原因之一。 相似文献
404.
405.
新疆与哈萨克斯坦寒武纪磷块岩资源 总被引:1,自引:0,他引:1
新疆和哈萨克斯坦寒武纪均为主要的磷矿成矿时代之一,但所形成的磷块岩资源量差别巨大.新疆寒武纪磷块岩矿层薄、矿石质量差、储量很少,哈萨克斯坦小卡拉套山寒武纪磷块岩矿层厚度大、矿石质量好、储量巨大.从实施“走出去”战略出发,邻国小卡拉套地区丰富的磷矿资源对于弥补新疆磷矿资源的严重不足具有重要意义. 相似文献
406.
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408.
Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea oftransport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory.Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/Magnesium in the mining of salt deposits in Qarhan Salt Lake. 相似文献
409.
LI Wenpeng 《《地质学报》英文版》2008,(5)
Firstly,the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory.The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented,which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake.And secondly,with a model forming idea of transport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference,a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory. Meanwhile,the model was applied to model potassium/magnesium transport in Qarban Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/ Magnesium in the mining of salt deposits in Qarban Salt Lake. 相似文献
410.
CHEN Jing''''an WANG Fushun WAN Guojiang TANG Degui David Dian ZHANG HUNAG Ronggui LI Jian XIAO Tangfu 《《地质学报》英文版》2008,82(5)
The correlation between the Δ13c and 18O in primary carbonates is affected by several factors such as hydrological balance, total CO2 concentrations, climatic condition and lake productivity.The influence of these factors on the Δ13c-δ18 correlation may be different on different time scales. In this paper, two different-type lakes in southwestern China, Lake Erhal and Lake Chenghai, are selected to investigate the influence of climatic pattern on the Δ13c-Δ18o correlation and to evaluate the reliability of the Δ13c-Δ18o covariance as an indicator of hydrological closure. The results show that there exists good correlation between the Δ13c and Δ18o in Lake Erhai (overflowing open lake) and inLake Chenghal (closed lake). This suggests that the Δ13c-Δ18o covariance may be not an effective indicator of hydrological closure for lakes, especially on short time scales. On the one hand, a hydrologically open lake may display covariant Δ13c and δ18 as a result of climatic influence. The particular alternate warm-dry and cold-wet climatic pattern in southwestern China may be the principal cause of the Δ13c-δ18 covariance in Lake Erhai and Lake Chenghal. On the other hand, a hydrologically closed lake unnecessarily displays covariant trends between Δ13c and δ18 because of the buffering effect of high CO2 concentration on the Δ13c shift in hyper-alkaline lakes. We should be the buffering feeect of high CO2 concentration on the 13Cshift in hyper-alkaline lakes.We should be prudent when we use the covariance between 13C and 18O to judge the hydrological closure of lake. 相似文献