尖晶石在地幔橄榄岩部分熔融和亚固相平衡过程中的化学指示——实验研究及在自然岩石中的应用

以三组不同的重组的尖晶石橄榄岩为起始成分.在压力为0.10—0.15GPa和温度为1000—1380℃条件下,进行了系统的部分熔融和亚固相平衡实验。实验结果显示,在部分熔融过程中,尖晶石的Mg＃,即Mg/(Mg+Fe),和Cr＃,即Cr/(Cr+Al),随熔融度的增大而增大;在亚固相平衡过程中,尖晶石的Mg＃随温度的升高而增大,但Cr＃在纯橄榄岩中保持不变,而在二辉和方辉橄榄岩中稍有增大。尖晶石的Mg＃—Cr＃间反相近线性代表了一种非整体平衡的等热关系。计算模拟得到同样的结果。这同时被自然橄榄岩中尖晶石的Mg＃—Cr＃间的关系所证明。由于亚固相条件下平衡的结果,尖晶石的化学成分中只有Cr＃变化不大,故能用来衡量其所在岩体曾经受的相对熔融度。即尖晶石的Cr＃越大,所在岩体经受的熔融度越大。相反,尖晶石的Mg＃和Cr＃在岩浆结晶过程中应随温度的降低而减小;因此,可用玄武岩中尖晶石的Cr＃来指示其岩浆的原始Cr_2O_3/Al_2O_3特征,及用尖晶石的环带特征来探讨岩浆的演化(冷却速度,混染情况)。     

川西义敦岛弧北段的古海相火山机构

在对川西义敦火山弧北段三种不同类型火山机构进行恢复工作后，总结出川西古海相火山机构的一般特征与火山机构恢复的基本方法．     

新疆金矿及其找矿远景分析

按金矿的集中分布区介绍了新疆１１个主要岩金产全区金矿的地质分布。成矿特征、控矿因素和矿床类型。对新疆金矿的找矿远景作出评估。认为新疆存在有利的金矿成矿条件，指出了找矿方向，提出了在新疆要重视对大型一特大型金矿研究。     

Evaluation of Experimental Procedures and Discussion of Two Different Modelling Approaches with Respect to Long-term Kinetics of Metal Cation Sorption onto (Hydr)oxide Surfaces

Experimental procedures as well as literature data and modelling of long-term kinetics of metal ion adsorption processes onto thermodynamically stable (hydr)oxide surfaces from aqueous solution are evaluated. It is concluded that when experimental uptake data are obtained by the solution depletion method precise information on experimental procedures is crucial. This is true both for preliminary kinetics studies (which intend to fix an equilibration time used for subsequent thermodynamic studies) and for true kinetic studies. For the usually given adsorption versus time curves the corresponding (possibly changing) values of pH should be added. The use of sorption pH edges measured at different times to obtain kinetics curves at constant pH may not correspond to the actual behaviour of the system but be rather an artificial construct.Concerning the models two basically different mechanisms have been used to account for the slow sorption step, which occurs in long-term studies: intraparticle diffusion of the adsorbing metal cation and slow redistribution of surface species. It is shown that the two mechanisms cannot be distinguished using macroscopic uptake data alone: data, which have been interpreted using one approach, may equally well be interpreted using the other one.     

桂北含锡花岗岩形成机理的实验研究

实验证明雪峰期含锡黑云母花岗岩是由元古宙四堡群变质岩在500×10~5—2000×10~5Pa的压力和750—570℃的温度范围內,经过重熔再结晶而成,而且进一步证实含F和B的水溶液对降低成岩的温度起了重要的作用。实验的结果与野外实际情况相符,揭示了含锡黑云母花岗岩形成的机理,阐明了它的形成在中国南方地壳动力学上的意义。     

AN EXPERIMENTAL STUDY OF SHEET EROSION IN GRANITIC REGION OF WUHUA COUNTY,GUANGDONG PROVINCE

1.IntroductionWuhuaCounty,locatedintheupstreamOfHanjianghiver,isoneofthemostseriouslyerodedcountiesinSouthChinagraniticweatheringregionOfGUangdOngPrOvince.ByinveStighion,thetOtalerodedareaisestimatedtobe875.33km,whichoccupiedbot30percentofthetOtalerodedareaoftenmostseriouserodedcountiesintheregion.Insomeconununes,theeroddareaevenreachedtomorethan6Opercent.ErosionresuItedinwidesPedOfbemountalns,landdopadaion,shortOfwterresourceshoperecotw.~ngthethreetypesoferosionintheupstreamOfHanjian…     

LY-921计算机实验装置的总体设计与调试

本文介绍LY—921计算机原理实验装置的总体结构设计和整机调试。该装置能进行计算机部件实验,整机实验以及小型数字系统调试等实验。     

缩套型高温高压三轴室热应力分析

以８００ＭＰａ高温高压三轴室为例，介绍了简体热应力计算方法和结果。分析讨论了热应力对筒体安全性的影响，指出高温差低载荷是最危险的情况，并提出预防与解决的方法。     

鄂东南地区印支-燕山期区域构造变形的实验研究与动力学分析

本文根据国内已建成通车的高速公路运行调研资料，结合高速公路线形设计经验，就有关问题进行分析探讨。提出了对高速公路线形设计的几点看法和意见，供应用参考。