黑河中游夏季昼夜水汽同位素特征及水汽来源分析

基于2012年6～8月的实测水汽同位素数据及相关气象数据,对黑河中游夏季昼夜的同位素基本特征、水汽来源方向及潜在蒸发源地进行了研究。结果表明:空气水汽线斜率白天大于夜晚和水汽过量氘值白天大于夜晚,综合说明白天局地蒸发较夜晚强烈;夏季受西风水汽影响显著。其中,6月主要受西风水汽和北冰洋水汽影响,7、8月主要受西风水汽和东南方向水汽影响,且8月受东南方向水汽影响最为明显;水汽运移路径上下垫面地形和气压带移动会影响水汽后向轨迹高度,西北方向上水汽输送通道较顺畅,风速较大,有利于水汽的输送;水汽蒸发源地主要集中在研究区周围及以东、以北部,其次是西北部。绿洲是主要的水汽蒸发源地,其次是城市和河流,白天较夜晚局地蒸发强烈且面积大。     

Mineral and fluid inclusions in zircon of UHP metamorphic rocks from the CCSD-main drill hole: A record of metamorphism and fluid activity

The Chinese Continental Scientific Drilling (CCSD) main drill hole (0–3000 m) in Donghai, southern Sulu orogen, consists of eclogite, paragneiss, orthogneiss, schist and garnet peridotite. Detailed investigations of Raman, cathodoluminescence, and microprobe analyses show that zircons from most eclogites, gneisses and schists have oscillatory zoned magmatic cores with low-pressure mineral inclusions of Qtz, Pl, Kf and Ap, and a metamorphic rim with relatively uniform luminescence and eclogite-facies mineral inclusions of Grt, Omp, Phn, Coe and Rt. The chemical compositions of the UHP metamorphic mineral inclusions in zircon are similar to those from the matrix of the host rocks. Similar UHP metamorphic P–T conditions of about 770 °C and 32 kbar were estimated from coexisting minerals in zircon and in the matrix. These observations suggest that all investigated lithologies experienced a joint in situ UHP metamorphism during continental deep subduction. In rare cases, magmatic cores of zircon contain coesite and omphacite inclusions and show patchy and irregular luminescence, implying that the cores have been largely altered possibly by fluid–mineral interaction during UHP metamorphism.

Abundant H₂O–CO₂, H₂O- or CO₂-dominated fluid inclusions with low to medium salinities occur isolated or clustered in the magmatic cores of some zircons, coexisting with low-P mineral inclusions. These fluid inclusions should have been trapped during magmatic crystallization and thus as primary. Only few H₂O- and/or CO₂-dominated fluid inclusions were found to occur together with UHP mineral inclusions in zircons of metamorphic origin, indicating that UHP metamorphism occurred under relatively dry conditions. The diversity in fluid inclusion populations in UHP rocks from different depths suggests a closed fluid system, without large-scale fluid migration during subduction and exhumation.     

西藏班戈县东嘎花岗岩体特征及锡找矿前景分析

东嘎花岗岩体位于冈底斯一念青唐古拉板片北缘、班公错一怒江结合带中段班戈一崩错板片。岩体时代为燕山晚期,属印度一欧亚板块碰撞造山构造环境。岩石属富钠、硅铝过饱和类型,该岩体位于斑戈一嘉黎一波密一察隅锡成矿远景带内,岩浆分异程度高,具有S型花岗岩体的典型特征,与滇西、川西含锡花岗岩体特征相似,成矿条件有利。区域化探资料显示锡异常明显,异常为Sn、Rb、Y、u、Nb、Ag、w、Th、Pb等多元素组合。sn元素的强度高、规模大。据区域地质、岩石化学及地球化学特征及区域成矿资料,东嘎花岗岩体具有良好的锡成矿前景。     

渤海中南部悬浮物海洋调查资料分析

对于悬浮物 (SPM)的研究目前已引起诸多学者关注。作者利用 1998和 1999年的中德合作海洋调查所获得的资料进行分析。主要进行三个方面的工作 :研究悬浮物与透明度的关系 ;研究悬浮物与浊度的关系 ;估计海底剪切速度。并为研究悬浮物输运提供资料和作前期研究     

新型节水灌溉控制原理的应用研究

在土壤-植物-大气连续体系(SPAC)中,以植物茎、果微增长及其含水量变化作为植物需水信息建立的灌溉自动控制系统,可实现植物水分适度亏缺,有效调控其生长发育。实验结果表明,同充分供水的植株或树体相比,节水15.6%时,玉米长势良好,节水21.4%时,柑桔果实生长未受影响。     

Estimation of critical state-related formula in advanced constitutive modeling of granular material

Different critical state-related formulas, for the critical state line and the critical state-dependent interlocking effect, have been proposed in constitutive modeling of granular material during last decades, which rises up a confusion on how to select an appropriate model in the geotechnical applications. This paper aims to discuss the selection of these critical state-related formulas and parameters identification. Three formulas of critical state line together with two formulas of critical state-dependent interlocking effect are combined to propose six elasto-plastic models. Drained and undrained triaxial tests on four different granular materials are selected for simulations. In order to eliminate artificial errors, a new hybrid genetic algorithm-based intelligent method is proposed and used to identify parameters and estimate simulations with minimum errors for each granular material and each model. Then, the performance of each CSL and each state parameter is evaluated using two information criteria. Furthermore, the performance was evaluated by simulating three footing tests using finite-element analysis in which the models are implemented. All comparisons demonstrate the incorporation of nonlinear critical state line combined with the state parameter e/e _c in constitutive modeling can result in relatively more satisfied simulated results.     

黄海冷水域水化学要素的垂直分布特性

黄海夏季深层冷水(简称黄海冷水), 又称为黄海冷水团, 已为海洋物理学家进行过较多的研究。该水域化学研究开展较晚，近年来顾宏堪首先报道了黄海夏季溶解氧垂直分布最大值与黄海冷水密切相关。黄海冷水与其它水团一样，理、化、生物等特性是相互关联的统一体。遗憾的是，迄今尚未见到有关于此的多学科综合性的研究报道。 本文根据1959年海洋调查资料，对黄海冷水域主断面水文化学要素的垂直分布特性进行了研究，并讨论了该冷水形成及诸参数变化的原因。     

滇西北高原强对流天气客观物理量特征分析

应用MICAPS客观物理量资料,对丽江市2006—2011年82次强对流天气进行诊断分析。结果表明,强对流天气发生前,水汽大多处于高湿或中等湿度状态,一般暴雨时700hPa比湿大于等于9g/kg,冰雹时大于等于6g/kg,或700hPa相对湿度暴雨时大于等于80%,冰雹时大于等于60%;热力状况大多处于高温、高热、高能和对流不稳定状态,部分在川滇间有明显的能量锋存在,特别是暴雨,一般沙氏指数SI小于等于0℃、K指数大于等于35℃、丽江假相当位温θse大于等于68℃,丽江与西昌或成都间的θse差大于等于10℃;动力条件则大多表现为低层正涡度,高层负涡度的有利配置,部分中高层有明显的冷平流,特别是冰雹时,一般700hPa涡度大于等于0×10-5s-1,300hPa以上任一层涡度小于等于-30×10-5s-1,或700hPa层以上任一层温度平流小于等于-1×10-5℃·s-1。     

土壤类型及组分对热活化过硫酸盐氧化降解土壤中挥发性氯代烃的影响

为了探究高级氧化技术对土壤中有机氯代烃的氧化降解作用,为ISCO（in situ chemical oxidation）技术体系提供重要的理论依据和数据支撑,考察了热活化过硫酸盐（persulfate,PS）氧化降解不同类型土壤（砂类土壤、黏土类土壤）中挥发性氯代烃污染物（三氯乙烯（TCE）、三氯乙烷（TCA）、顺式-1,2-二氯乙烯（cis-1,2-DCE）、1,2-二氯乙烷（1,2-DCA））的效能;同时,通过硫酸盐与土壤相互作用过程研究,探究了不同土壤介质中有机质和无机组分在过硫酸盐消耗中所占比例。结果表明：在50℃时,热活化过硫酸盐可有效降解土壤中1,2-DCA、cis-1,2-DCE、TCA和TCE,砂类土壤介质中4种氯代烃降解效果依次为25%、89%、5%和61%,黏土类土壤介质中4种氯代烃降解效果依次为35%、86%、8%和63%;4种氯代烃的降解效果从高到低顺序依次为cis-1,2-DCE、TCE、1,2-DCA、TCA,砂类土壤中的氯代烃总体降解效果优于黏土类土壤中氯代烃的降解效果。另外,土壤中过硫酸盐氧化降解氯代烃反应研究发现,砂类和黏土类土壤介质组分中有机质消耗率分别为81.3%和72.6%,铁元素消耗率分别为80.5%和38.6%,表明土壤介质组分与过硫酸盐发生了氧化还原反应,从而导致过硫酸盐自身的大量消耗。由此可知,土壤介质中的有机质、铁元素等矿物质均参与过硫酸盐的消耗过程,且土壤有机质、铁元素与氯代烃之间在消耗过硫酸盐反应上存在竞争关系,土壤组分过多地消耗了过硫酸盐,导致了氯代烃的氧化降解效率较低。因此,针对实际有机氯代烃污染场地,采用过硫酸盐氧化技术进行修复时,过硫酸盐的实际投加量要远高于化学计量值,需充分考虑到土壤组分对过硫酸盐自身的消耗作用。