含片钠铝石砂岩与地层水相互作用实验

不同温度(100℃、150℃和200℃)地层水对含片钠铝石砂岩的改造作用研究显示,随着温度升高,砂岩的溶解程度逐渐增强,样品中片钠铝石的稳定性逐渐减弱。在片钠铝石溶解的同时,200℃时样品表面有高钠长石和绿泥石生成,且通过X-射线衍射分析发现,在150℃和200℃时有某种未知的碳酸盐矿物生成,生成量随温度升高而增大。100℃时片钠铝石的微弱溶解及150℃和200℃时碳酸盐矿物的生成表明,在地层条件下以片钠铝石等碳酸盐矿物形式捕获的CO2能够稳定存在。     

CO2流体对含片钠铝石砂岩改造作用的实验研究

不同温度（100℃,200℃和300℃）下CO_{2流体对含片钠铝石砂岩的改造作用研究显示:随着温度的升高,砂岩的溶蚀、溶解程度逐渐增强,样品中片钠铝石的稳定性逐渐减弱。同时,各温度下样品表面均有一水软铝石放射状集合体沉淀。200℃时,随着片钠铝石的溶解有自生菱铁矿生成,300℃时样品局部有绿泥石沉淀。100℃下片钠铝石的微弱溶解及200℃下菱铁矿的形成表明,在地层条件下以碳酸盐矿物形式捕获的CO2,不会由于CO2的二次注入而重新释放。}     

温室气体CO2与钠长石相互作用实验研究

为寻求减缓全球变暖的途径,利用高压釜,开展不同温度下(75、100、125、150和175℃)CO₂与钠长石的水热实验研究,以探讨CO₂在长石砂岩中地质封存的可能性。结果表明,随着温度的升高,钠长石溶蚀强度逐渐增强,在150℃左右开始有菱镁矿、菱铁矿等碳酸盐矿物生成,175℃新矿物生成量增加,这表明CO₂能够以碳酸盐矿物的形式在含钠长石的长石砂岩中以矿物的形式被“固定”,其被“固定”的温度在150℃左右。     

海拉尔盆地乌尔逊凹陷片钠铝石的碳氧同位素组成及流体来源探讨

作为胶结物或交代自生矿物,片钠铝石(分子式为NaAlCO_3(OH)_2)大量发育于海拉尔盆地乌尔逊凹陷下白垩统南屯组、大磨拐河组砂岩中。根据片钠铝石稳定同位素组成,探讨了片钠铝石中碳的来源。片钠铝石的δ~(13)C分布连续,其范围为-5.253‰～-1.210‰(PDB),δ~(18)O分布范围为-24.896‰～-20.960‰(PDB),考虑到海拉尔盆地探井中未钻遇碳酸盐地层,片钠铝石属岩浆成因碳酸盐范畴。结合与片钠铝石平衡的CO_2的δ~(13)C值,含片钠铝石井和幔源CO_2气井分布相吻合且位于燕山期花岗岩或附近的深大断裂带上,认为海拉尔盆地乌尔逊凹陷岩浆活动-砂岩成岩(片钠铝石形成)-幔源CO_2气成藏不论在物质成分上还是在时空上均具备较好的耦合关系,形成片钠铝石所需的CO_2气为与燕山期岩浆作用有关的幔源CO_2气,深大断裂是深部CO_2气向上运移到浅部砂岩的主要通道,片钠铝石形成时因油气充注而介入少量生物成因碳。     

沉积岩中无机CO2热模拟实验研究

结合三水盆地的地质特点，分析了无机CO₂热模拟实验研究的可能性，进行了不同条件下的模拟试验和相关的分析测试，提出了无机CO₂生成量和转化率的概念和计算方法。从实验结果来看：含有一定量碳酸盐矿物的沉积岩，在一定温度下可转化形成相当数量的无机CO₂，无机CO₂转化率越高，岩石中碳酸盐矿物越容易转化生成无机CO₂；相同热成熟度条件下，Ⅱ型干酪根生成有机CO₂的量较Ⅲ型的少；CO₂中碳同位素与CO₂的成因密切相关，随有机质热成熟度的增加，同种类型有机质生成的有机CO₂相对富集¹³C；无机CO₂较有机CO₂的碳同位素明显富集¹³C，随水介质的pH值降低，无机CO₂气含量、模拟温度及时间的增加，无机CO₂相对富集¹³C。实验研究结果为CO₂成因研究及其资源评价提供了实验依据。     

含片钠铝石砂岩的基本特征及地质意义

含片钠铝石砂岩是一种含片钠铝石自生矿物的砂岩，一般为富含长石的砂岩，与片钠铝石稳定共生的自生矿物主要为铁白云石、菱铁矿等碳酸盐矿物。砂岩中片钠铝石的含量变化较大，其存在与否不受砂岩结构的制约。含片钠铝石砂岩往往分布在断裂和岩浆岩体附近，既可以作为CO2气储层，又可以作为油气储层。含片钠铝石砂岩是一种具有特殊地质意义的砂岩，表现为：①含片钠铝石砂岩记录了深、浅部层圈之间及烃源岩—储层之间的物质转移；②在含油CO2气藏和油藏中，含片钠铝石砂岩记录了CO2与油气双重充注，其中含油CO2气藏中的含片钠铝石砂岩记录了CO2充注驱油现象；③含片钠铝石砂岩是进行CO2地下储存研究的理想的天然实验室。     

白云鄂博超大型稀土-铌-铁矿床成矿过程中的流体不混溶作用

白云鄂博超大型REE-Nb-Fe矿床赋存在白云岩内，矿体由磁铁矿、稀土氟碳酸盐、萤石、霓石、角闪石、方解石和重晶石等矿物组成。在白云鄂博矿床矿石和脉石矿物中赋存有两/三相富CO₂、三相高盐卤水和两相水溶液包裹体3大类型。显微测温表明富CO₂包裹体内还有近于纯的CO₂，成矿流体为H₂O-CO₂-NaCl-（F-REE）体系。高盐卤水包裹体和富CO₂包裹体共生且具有近似的完全均一温度，表明初始热液发生了流体不混溶作用。流体包裹体中出现稀土子矿物，表明初始成矿流体含有很高的稀土元素，这也许是形成白云鄂博超大型稀土矿床的原因。     

海拉尔盆地乌尔逊凹陷无机CO2气储层的岩石学与碳氧同位素特征

海拉尔盆地乌尔逊凹陷无机 CO_2气储集砂岩中含有大量片钠铝石,是查明无机 CO_2气注入对砂岩的改造和形成的自生矿物组合的理想砂岩。通过偏光显微镜、扫描电镜、X-射线衍射分析和 MAT253稳定同位素质谱仪等,确定了含片钠铝石砂岩中的胶结物与自生矿物类型、成岩共生序列和引起片钠铝石形成的 CO_2的成因。CO_2气注入前形成的自生矿物组合主要为方解石、次生加大石英和高岭石,在次生加大石英形成过程中发生了第一期油气注入。CO_2气注入晚于第一期油气注入,CO_2气注入后形成的自生矿物组合主要为片钠铝石和铁白云石。第二期油气注入发生在 CO_2气注入后。片钠铝石的δ~(13)C 为-5.3～-1.5‰PDB,与片钠铝石平衡的δ~(13)C_(CO2),为-10.7～-7.0‰PDB,与海拉尔盆地 CO_2气的δ~(13)C_(CO2)值(-11.36～-8.02‰PDB)一致,表明形成片钠铝石的 CO_2和气藏中的 CO_2均来源于无机 CO_2与有机 CO_2混合背景,总体上以无机 CO_2为主。结合含片钠铝石砂岩与 CO_2气的分布都受控于深大断裂和γ5花岗岩的特点,CO_2气和形成片钠铝石的 CO_2绝大部分属于幔源-岩浆型。含片钠铝石砂岩中保存了 CO_2驱油的迹象。     

莺歌海盆地乐东区片钠铝石特征及其对浅层CO2充注的指示

作为天然CO₂的示踪矿物,片钠铝石的形成与CO₂充注密切相关.莺歌海盆地乐东区乐东X构造莺歌海组-黄流组CO₂气藏内发育含片钠铝石砂岩,在开展的岩石学和地球化学研究基础上,确定了研究区片钠铝石的产状和纵向分布特征,分析了形成片钠铝石的“碳来源”和气水条件,进而探讨了与片钠铝石具有成因联系的CO₂的成因.乐东X构造含片钠铝石砂岩为细—极细粒长石石英砂岩和岩屑石英砂岩,片钠铝石主要以充填孔隙及交代颗粒的形式产出,是成岩共生序列中形成较晚的自生矿物之一.在纵向上,片钠铝石仅集中发育于高含CO₂气层的底部以及其下的水层中,这一分布特征以地质实例的形式证实了片钠铝石的形成需要水的参与.研究区浅层CO₂充注后形成的碳酸盐矿物为片钠铝石和铁白云石.片钠铝石的碳氧同位素特征表明形成片钠铝石的“碳”与LDX构造气层中CO₂具有相同的碳来源,以无机幔源成因CO₂为主.红河断裂以及莺歌海盆地中央坳陷内一系列底辟构造及伴生的垂向裂隙可能为CO₂的运移通道.      

CO_2流体与储层砂岩相互作用机理实验

储存于地下岩层中的CO2与矿物发生化学反应导致次生碳酸盐矿物的沉淀,CO2将以碳酸盐矿物的形式长时间地固结在储层岩石中,从而有效减少CO2向大气中的排放。通过对不同温度下CO2-H2O-砂岩相互作用机理的研究,以及反应后样品的扫描电镜观察、质量损失量和剩余反应液中总矿化度变化的分析发现:砂岩样品的溶蚀程度随温度的升高而逐渐增强;100℃和175℃时样品表面分别有方解石和白云石生成,250℃时新生成的矿物因温度过高而溶解。这表明CO2能够以碳酸盐矿物的形式固定在矿物中,175℃为本实验所证明较适合的贮存温度。     

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.     

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).     

NONMETALS DEPOSITS

正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)     

MATHEMATICAL GEOLOGY

正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,     

PROSPECTING EXPLORATION

正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)     

STRUCTURAL GEOLOGY

正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-     

STRUCTURAL GEOLOGY

正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with