高岭石的热稳定性和热处理产物的DTA IR和EPR研究

本文利用DTA、IR和EPR等方法研究了高岭石的热稳定性及100—900℃热处理产物的系统特征。高岭石的热稳定性会因为堆垛层错缺陷浓度的增大而降低。根据IR和EPR实验,所有高岭石热处理过程中的变化包括:脱羟前、脱羟和脱羟后三个阶段。小于400℃时,产物成分和结构同原高岭石相同,≥400℃开始产物的堆垛层错浓度增大并有利于继续升温后的脱羟过程。变高岭石可能介于晶质和非晶质之间。此外,高岭石Ⅰ位Fe~(3+)和变高岭石结构中的Fe~(3+)可能有某些相似的特征。     

热处理低温钠长石的EPR和X射线衍射研究

利用电子顺磁共振(EPR)和X射线衍射方法研究了天然和热处理钠长石单晶。热处理在500—850℃水热条件下完成。在外加磁场B平行于晶体c~*轴的方向上,测量了加热前后Fe~(3+)的EPR谱和线宽△B随温度和加热时间的变化。结果显示,线宽随Al、Si无序的增大而增加。由此得出结论,在低温钠长石中,Fe~(3+)位于Al~(3+)占据的T_1(o)位置,在被研究的温度范围内,Fe~(3+)未参与四面体位置T间Al、Si交换。谱线的加宽主要是由在Fe~(3+)邻近位置上Al、Si无序的增大引起的,同时与观测到的晶胞参数变化有关。在Al、Si无序更强的晶体中,Fe~(3+)谱变得极宽。     

天然单斜辉石中Cr ~(3+)的晶位对称性和偏振吸收谱的分析

通过对单斜辉石系列钠铬辉石-硬玉样品中Cr~(3+)偏振吸收谱的谱带强度、形状及位置的分析,提出:这类矿物晶体中Cr~(3+)应处于四角畸变D_4对称晶场的晶位。由此计算出的谱带位置和观测结果一致。说明了D_4晶位假设更优于Khomenko等提出的三角畸变C_(3v)对称假说。     

碱性长石中Fe^3＋在四面体位置间交换动力学的EPR研究

在加热条件下,利用EPR方法研究了碱性长石中不同四面体位置间的Fe~(3+)、Al~(3+)交换。低温钠长石和透长石晶体分别在水热,1 kbar,500—900℃和干加热,1050℃条件下加热。在低温钠长石中,加热后Fe~(3+)线被加宽,当温度为800℃时,除T_1(o)位置外,没有出现其余四面体位置Fe~(3+)产生的谱线。透长石在1050℃加热1300h后,T_1和T_2线的相对强度发生了变化。实验表明,在碱性长石中不同四面体间Fe~(3+)、Ak~(3+)和Fe~(3+)、Si~(4+)交换与Al~(3+)、Si~(4+)交换比较,前者速度要缓慢得多。     

沉积岩中地开石-高岭石混层矿物的发现及成因探讨

1979年夏,笔者在河北省曲阳县灵山镇附近的石炭纪地层中,发现一种晶体巨大的高岭石族矿物,最大的晶粒沿C轴长度可达2厘米,(001)面的直径可达0.5毫米。由于晶粒巨大,易于挑选,引起了我们对其单矿物进行研究的兴趣。用多种手段对该矿物进行了矿物学研究,发现它既有高岭石的特征,又兼有地开石的特征,但它既不是简单的高岭石,又不是简单的地开石,而是一种地开石-高岭石的混层矿物。     

辽宁桓仁夕线石玉的宝石矿物学研究

近来实验室收到几块外观与和田玉极为相似的玉石样品,为了更好地鉴别该玉石,采用常规的宝石学测试、薄片分析、化学全分析、红外光谱分析、X射线粉晶衍射分析、拉曼光谱分析等方法对其进行了测试研究。结果表明,该玉石样品的主要矿物组成是夕线石,并含有少量的云母和高岭石,其结构为柱状纤维变晶结构,主要呈柱状、纤维状、毛发状分布,样品呈黑色的原因可能与晶格中Fe~(3+)替代Al~(3+)有关,Fe~(3+)含量越多颜色越深。     

“老挝田黄石”的物质组成特征

针对近年市场新出现的老挝"田黄"石,采用折射率仪、静水称重法等常规宝石学特征分析,并结合傅里叶红外光谱(FTIR)、电子微探针(EPMA)、X射线粉晶衍射(XRD)等大型仪器分析测试技术,对老挝田黄石的谱学特征进行了研究,并与寿山田黄石进行对比。结果表明,老挝田黄石与寿山田黄石均以高岭石族矿物为主,常规宝石学性质相近。老挝田黄石主要成分为地开石、高岭石及地开石-高岭石过渡矿物,与地开石质寿山石(高山石等)类似,不含珍珠陶石;寿山田黄石主要成分则为地开石、高岭石、珍珠陶石,部分样品含有白云母。     

煤系高岭岩的XRD曲线特征——对高岭石—地开石混层矿物XRD曲线特征的一点看法

根据高岭石基面衍射是否加强以及加强的程度,将我国煤系高岭岩的XRD曲线分为3种基本形态类型。介绍了3种XRD曲线的形态特征,并分析了造成高岭石XRD曲线差异的原因,同时否定了将基面衍射加强的高岭石看作高岭石—地开石混层矿物。      

波伏棱（Povlen）型羟基纤蛇纹石的谱学研究

波伏棱型羟基纤蛇纹石是波伏棱型纤蛇纹石矿物的新变种,本文报导它的吸收光谱、红外光谱、穆斯堡尔谱、电子顺磁共振谱和核磁共振谱。 研究表明,吸收光谱是Fe~(3 )和Fe~(2 )的晶场跃迁以及Fe~(2 )→Fe~(3 )的荷移跃迁引起的;红外光谱是OH和Si-O的伸缩振动、OH转动以及Mg-O和Si-O的弯曲振动引起的;穆斯堡尔谱是Fe~(2 )_(八面体)、Fe~(3 )_(八面体)和Fe~(3 )_(四面体)引起的;电子顺磁共振谱是Mn~(2 )_(八面体)、Fe~(3 )_(八面体)和Fe~(3 )_(四面体)引起的;核磁共振谱是管道水,镁八面体和硅氧四面体上的OH引起的;矿物加热到825℃时,结构开始破坏并出现镁橄榄石相。 此外,本文还解释了该蛇纹石颜色的本质,阐明了上述过渡金属离子和OH在该矿物中的结构环境。     

福建寿山高山石与坑头石的矿物学特征

运用显微硬度测试仪、静水称重法、X射线粉晶衍射仪、傅立叶红外光谱仪、原子吸收分光光度计、环境扫描电镜等测试手段,对福建寿山高山石和坑头石的矿物学特征进行了研究。结果表明,高山石含有多种高岭石族矿物,其中以地开石为主要矿物;坑头石中除含有地开石外,还存在相当数量的珍珠陶石以及地开石-高岭石、地开石-珍珠陶石的过渡矿物。认为寿山石的透明度与矿物颗粒的粒度、结晶程度有关。另外,发现铁离子为黑色寿山石的主要致色离子,寿山石中的裂解主要由矿物颗粒间定向排列造成。     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H₂O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H₂O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

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GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)     

GEOCHEMISTRY

正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861