Rietveld全图拟合法定量分析伊利石矿的精确度及误差来源

伊利石是一种重要的矿产资源,准确获得矿石中矿物组成和含量具有重要的理论和实际意义.Rietveld全图拟合法采用整个衍射图进行分析,具有较高的准确度.然而由于缺少纯的伊利石样品,目前对于该方法在分析伊利石矿样的精确度和误差来源尚不清楚.本文采用Rietveld全图拟合法对人工配制和天然的伊利石典型矿样进行了分析和计算,...     

山西晋城和阳泉地区石炭系太原组铵伊利石矿物特征及成因

铵伊利石是伊利石层间域的K+被NH+4替代而形成的类质同象.文中运用X射线衍射分析、傅里叶红外光谱分析以及热重—热流—红外光谱同步分析等手段,对山西晋城及阳泉地区的15号煤层夹矸及煤中矿物进行了研究,发现15号煤层夹矸和煤低温灰中黏土矿物以铵伊利石和高岭石为主,铵伊利石含量为21％～74％;X射线衍射图谱上d(001)...     

福建云霄岩田山伊利石矿地质特征及成因探讨

云霄岩田山伊利石矿床是福建境内新发现的少有的伊利石矿床。在对岩田山伊利石矿床形成地质特征总结基础上,通过对矿石XRD衍射和扫描电镜分析研究,认为岩田山矿床是以伊利石矿物为主的伊利石矿,矿床成因属低温热液蚀变型伊利石矿床,风化作用对矿石起到了改造(良)作用。     

自生伊利石同位素年代学在钾盐矿床中的应用展望

伊利石是一种层状硅酸盐矿物,层间主要为钾离子,可利用K-Ar法、Ar-Ar法和Rb-Sr法等相关的测年方法来分析和限定与自生伊利石有关的地质事件的时代,例如盆地演化历史、热液活动、构造活动和油气运移。本文讨论了利用钾盐矿床中自生伊利石进行蒸发岩地层年代学研究的可能性。虽然多数研究表明温度是控制自生伊利石形成的主要控制因素,即自生伊利石一般形成于温度较高的条件下,但一些研究表明在地表温度的盐湖环境中也可形成自生伊利石,此种环境下控制自生伊利石形成的主要因素为流体成分。这构成了利用自生伊利石定年来研究蒸发岩地层时代的理论基础。然而在实际研究过程中仍存在很多问题,需进行进一步的研究。     

陕西洛川黄土-古土壤剖面中伊利石结晶度——黄土物质来源和古气候环境的指示

伊利石是我国黄土和古土壤中最主要的粘土矿物。本文选择陕西洛川黄土-古土壤国际典型剖面为研究对象,通过测定伊利石的结晶度(Kubler指数)、Srodon峰强比值(Ir)和2M_1多型含量,发现黄土物质的起源与中高温(>280℃)地质环境有关;黄土样品中伊利石结晶度值为0.25°2θ(Cu Ka),古土壤样品中伊利石结晶度值大于0.27°2θ(Cu Ka);黄土和古土壤中伊利石结晶度值的差别,是由于古土壤中伊利石含少量的膨胀层,而黄土样品中的伊利石不含有膨胀层而引起的。古土壤中伊利石的膨胀层的成因,与伊利石     

天津蓟县二维纳米级伊利石研究

天津蓟县中元古界串岭沟组上部黑色页岩产有丰富的伊利石,其矿物组合仅为石英和伊利石,是重要的可利用伊利石资源。运用化学成分分析和XRD方法确定出伊利石含量为64％～70％。由Scherrer方程计算的平均c^*轴方向厚度为12nm,平均6轴方向长度为167nm,结合伊利石的片状生长习性,可确定串岭沟组上部黑色页岩所产伊利石为二维纳米级伊利石,具有重要的纳米属性。化学成分分析表明,黑色页岩所产伊利石具有0．75的层间电荷和二八面体为主的二八-三八面体的过渡类型八面体结构特点。对数正态粒度大小的分布特征表明黑色页岩中的伊利石经历了由成核→等体积转移→最终长大的Ostwald成熟效应。     

伊利石40Ar-39Ar年龄的统计分析与成藏期

为了确定鄂尔多斯盆地苏里格气田的成藏年代,通过提取砂岩储层中的黏土质填隙物,分离分级成 < 0.5、0.5~1.0、1.0~2.0μm的分样品,进行伊利石激光阶段加热40Ar-39Ar定年.等时线年龄是自生伊利石与碎屑伊利石的混合年龄.通过趋势分析和回归分析分别获得极小的趋势年龄和极小的回归年龄,该年龄比较接近自生伊利石年龄.测试结果表明,伊利石的等时线年龄介于160.9~232.0 Ma之间,为自生伊利石与碎屑伊利石的混合年龄.采用数理统计方法获得极小趋势年龄和极小回归年龄分别为151.7 Ma和152.4 Ma,该年龄比较接近自生伊利石年龄,代表了热流体活动和油气成藏时间.      

东昆仑阿拉克湖早更新世沉积物黏土矿物特征及其古气候环境意义

为了揭示东昆仑阿拉克湖地区早更新世的气候环境演化,利用X射线衍射、扫描电子显微镜以及古地磁对位于东昆仑山系东段的阿拉克湖断陷盆地早更新世沉积物样品进行了分析.结果表明,黏土矿物的成分主要为伊利石和绿泥石,含有少量的高岭石.伊利石结晶度在0.280～0.513°之间,反映伊利石结晶度存在明显的差别.古地磁分析结果显示,磁化率介干14.85×10-6～214.20×10-6SI之间,平均为68.41×10-6SI,也存在着明显的变化.ω(Kao)/ω(I Ch)比值在0.11～0.22之间,反映不同时期沉积物中高岭石与伊利石、绿泥石之间相对含量的变化.ω(Kao)/ω(I Ch)比值、伊利石结晶度以及古地磁分析结果的变化特征,均反映了东昆仑阿拉克湖的古气候经过了从冷干到温湿的气候变化,而沉积物以伊利石和绿泥石为主以及相对较高的伊利石结晶度和偏低的磁化率值则说明早更新世阿拉克湖地区的气候总体以冷干为主.     

大安油田泉四段自生伊利石对致密砂岩优质储集层的影响

大安油田泉四段自生伊利石普遍存在于岩石孔喉中,主要以3种产状分布:1分布在碎屑颗粒表面的蜂窝状伊利石,由蒙皂石转化而来;2由高岭石转化的丝状伊利石,常以搭桥式分布在岩石颗粒之间或其他黏土矿物边缘;3片状伊利石,可能是由蒙皂石转化或直接结晶形成的。从表面上看,储集层孔喉中发育的自生伊利石会增加喉道弯曲度,减小孔隙空间。但伊利石同时也会防止石英次生加大而对储集层孔隙度起保护作用,并且伊利石的形成也会促进钾长石溶解形成次生孔隙。综合来看,自生伊利石对储集层物性起促进作用。通过垂向储集层物性及自生伊利石含量确定主力油层,并叠合主力油层沉积微相图和成岩相,判定平面上伊利石含量较高的A区和胶结程度较弱的B区为今后勘探有利目标。     

伊利石结晶度Kübler指数的校正与近变质带的确定

就像用"砝码"标定"称"来测量物质质量一样,伊利石结晶度的测量也需要这样的"砝码"标定它的测量工具——衍射仪,从而能够进行伊利石结晶度的测量和对比。这个砝码就是伊利石结晶度标样或称伊利石结晶度国际标样。第2届Kübler-Frey国际研讨会伊利石结晶度圆桌会议就伊利石结晶度标样和近变质带的确定的问题进行了深入的讨论。会议一致认为,用伊利石结晶度标样校正X射线衍射仪是极为重要和必要的,没有进行标样校正的伊利石结晶度数据将被拒绝发表,经过伊利石结晶度国际标样校正后的伊利石结晶度数据才可用于近变质带的划分和国际对比。本文就伊利石结晶度测量的有关衍射仪类型与差别,衍射仪系统,测量条件,样品的影响和国际标样对仪器的校正等问题进行了分析研究。结果表明不同型号仪器,同型号仪器不同测量条件与状态,样品的不同制备方法都将影响伊利石结晶度Kübler指数的测量。指出只有使用国际标样才可校正测量的伊利石结晶度Kübler指数,从而达到消除偏差准确划分近变质带的标准和进行国际对比的目的。     

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.     

Définition d'une limite multicritère ; stratigraphie du passage Campanien–Maastrichtien du site géologique de Tercis (Landes,SW France)Definition of a multi-criteria boundary; stratigraphy of the Campanian–Maastrichtian interval of the geological site at Tercis (Landes,SW France)

Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.     

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.     

Late Wuchiapingian (Late Dzhulfian,early Late Permian) limestone olistolites within the Tertiary flysch of Glypia Unit (Mount Parnon,central–eastern Peloponnesus,Greece)

Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.     

PALEONTOLOGY

正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)     

GEOCHEMICAL EXPLORATION

正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)     

MICROPALAEONTOLOGY

正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)     

PETROLOGY

正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,     

ENVIRONMENTAL GEOLOGY

正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an     

PROSPECTING EXPLORATION

正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of