怀安—大同一带基性麻粒岩变质反应序列与水活度

晋冀蒙三省交界的怀安－大同一带基性麻粒岩有保存完好的变质反应结构。依据岩相学特征，可在基性麻粒岩中区分出四个世代的矿物组合：①峰前阶段（Ｍ１）以包裹在石榴石或紫苏辉石中的Ｈｂ＋Ｐｌ±Ｑｚ、Ｃｐｘ＋Ｈｂ＋Ｐｌ±Ｑｚ组合为代表，Ｔ为６００℃～７００℃，Ｐ为０．７０～０．８２ＧＰａ，相应的ａＨ２Ｏ值为０．５０～０．６２；②峰期阶段（Ｍ２）以三联点结构的基质矿物为特征，组合为Ｏｐｘ＋Ｃｐｘ＋Ｈｂ＋Ｐｌ±Ｑｚ、Ｇｔ＋Ｏｐｘ＋Ｃｐｘ＋Ｈｂ＋Ｐｌ±Ｑｚ，Ｔ为７５０℃～８５０℃，Ｐ为０．８４～１．０５ＧＰａ，相应的水活度降至０．３９～０．５２；③峰后近等温减压阶段（Ｍ３）以石榴石普遍转变为Ｏｐｘ＋Ｐｌ±Ｍｔ及角闪石转变为Ｏｐｘ＋Ｃｐｘ后成合晶为特征，Ｔ为７００℃～７８０℃，Ｐ为０．５０～０．７０ＧＰａ，相应的ａＨ２Ｏ值降至０．０８～０．１１；④至降温阶段（Ｍ４），以无水矿物石榴石、辉石退变为Ｈｂ＋Ｐｌ组合为代表，Ｔ为５３０℃～６３０℃，Ｐ为０．３０～０．４２ＧＰａ，ａＨ２Ｏ值再次升至０．３７～０．４０。研究表明，矿物组合演化和所发生的（脱水）变质反应不仅受ＰＴ条件的控制，而且与体系水活度密切相关     

勉县地区勉略带内麻粒岩的发现及构造意义

勉县菜马河南部徐家坪附近勉略带中多处发现基性麻粒岩岩块,基矿物共生组合为：Ｃｐｘ＋Ｇｔ＋Ｐｌ（Ａｎ３０）＋Ｑｚ＋Ｒｕｔ。采用Ｅｌｌｉｓ等温度计获得Ｔ为６５７￣７７２℃,采用Ｎｅｗｔｏｎ等压力计获得峰值Ｐ达０．８２￣１．１７ＧＰａ考虑到该压力计获得值往往偏低,校正后压力最高达０．９７￣１．３２ＧＰａ。基性麻粒岩中存在Ｇｔ＋Ｃｐｘ＝Ｈｂ＋Ｐｌ的退变反应,表明经历了等温降压过程,ＰＴｔ轨迹为顺时针,反映     

大别山北部石榴二辉麻粒岩变质结构特征

通过对大别山北部石榴二辉麻粒岩中的变质结构及变质反应特征的研究,认为石榴二辉麻粒岩在变质作用过程中,经历了四个主要的变质演化作用阶段：（１）Ｓ１阶段以早期的残留矿物,并呈包体的形式产于石榴石中为特征,以Ｃｐｘ＋Ｑ（Ｃｓ）＋Ｒｕ＋Ｇｔ组合为代表,Ｔ＝６１２～７５０℃,表明石榴二辉麻粒岩曾经历过榴辉岩相阶段的变质作用;（２）Ｓ２阶段是以Ｏｐｘ＋Ｃｐｘ＋Ｇｔ＋Ａｍｐ＋Ｑ＋Ｔｉ＋Ｍｔ矿物组合为牲,其相应的Ｔ＝８３７～８８７℃,Ｐ＝１．０３～０．９５Ｇｐａ,此时的变质条件为麻粒岩相;（３）Ｓ３阶段,矿物组合为Ｃｐｘ＋Ｇｔ＋Ａｍｐ＋Ｐｌ＋Ｍｔ,Ｔ＝５３０～６６０℃,Ｐ＝０．８５～０．９５Ｇｐａ,此时的温故知新压条件代表岩石已经进入了角闪岩相阶段;和（４）晚期的低角闪岩相阶段Ｓ４,其形成的温压条件为Ｔ＝４９５℃,Ｐ＝０．５６～０．７０Ｇｐａ。     

大别山区深部地壳的变质岩石学证迹：罗田惠兰山一带的麻粒岩研究

大别杂岩中新太古代或古元古代麻粒岩相岩石分布具一定的区域规模。罗田黄土岭、惠兰山一带出露中性和基性麻粒岩，其矿物组合分别为；１．Ｇｒｔ＋Ｏｐｘ１＋Ｂｉ＋Ｋｆｓ＋Ｐｌ（Ａｎ２０）（中性），２．Ｇｒｔ＋Ｈｂ１＋Ｏｐｘ＋Ｃｐｘ＋Ｐｌ（Ａｎ４Ｏ）＋Ｉｌｍ（基性），它们的高峰变质条件分别为ＰＯ．８９～１．０４Ｇｐａ、Ｔ７５０～８５０℃（中性）以及Ｐ０．９～１．２９ＧＰａ、Ｔ６８２～８８０℃，平均７７１±５３℃（基性），说明其形成深度在３０ｋｍ以上。在中性麻粒岩中发现堇青石＋石英和堇青石＋黑云母的后成合晶，分别位于Ｇｒｔ与Ｏｐｘ１之间或穿插于Ｇｒｔ晶内，退变质反应条件为Ｐ为０．４１～０．５５ＧＰａ，Ｔ＝７１０℃，属减压退变质性质；后成合晶的形态与区域面理无关，说明减压退变质反映了碰撞造山带后期的近绝热隆升。区域花岗岩或地幔热流可能是绝热隆升的热源，现今出露的深源麻粒岩有过长期居留下地壳的历史，它们的抬升剥露是后期构造事件所致。     

胶东莱西地区高压基性麻粒岩的变质作用

胶东地区莱西－莱阳－栖霞－带晚太古代花岗片麻碉中,出露相当规模的高压基性麻业岩和超镁铁质岩组合,曾被认为它们是与苏鲁－大别超高压碰撞造山作用有关的一套岩石组合,高在性麻粒岩中可同三期变质矿物组合;早期为Ｇｒｔ核部）＋Ｃｐｘ＋Ｐｌ;中期为Ｇｒｔ（边中）＋Ｃｐｘ＋Ｏｐｘ＋Ｐｌ＋Ａｍｐ＋Ｑ＋Ｍｔ;晚期为Ｃｐｘ＋Ｐｌ＋Ａｍｐ＋Ｑ＋Ｍｔ。早期的石榴石含钱铝榴石和镁铝榴石组分较高,单斜辉石含Ａｌ高。应用矿物温     

晋蒙边界富铝片麻岩的矿物演化序列及动力学意义

华北地台北缘早前寒武纪孔兹岩系的变质反应结构及矿物组合演化序列在晋蒙边界地区代表性岩石；夕线石榴黑云钾长（二长）片麻岩（Ａ）和石榴（紫苏）黑云斜长片麻岩（Ｂ）中保存的最为完整，以岩相学及显微组构特征为依据，可将其划分四个世代的矿物组合；（１）峰前以含蓝晶石残晶和包裹于平衡镶嵌，出现典型的麻粒岩相矿物组合；Ｋｙ±Ｇｔ＋Ｋｆ±ｐｌ＋Ｑｚ（Ａ），Ｂｉ±Ｇｔ＋Ｐｌ＋Ｑｚ（Ｂ）；（２）峰期以基质矿物平衡镶嵌     

辽西建平变质杂岩区蠕虫状后成合晶的成因与意义

建平变质杂岩中发育蠕虫结构的后成合晶，它受与石榴石共生的矿物组合、变质流体中水活度和变质岩原岩的制约。这种后成合晶可出现四种矿物组合：（１）Ｏｐｘ＋Ｐｌ＋少量Ｃｐｘ，（２）Ｏｐｘ＋Ｍｔ＋Ｐｌ＋Ｑ＋少量Ｃｐｘ，（３）Ｈｂ＋Ｐｌ，（４）Ｃｏｒｄ＋Ｏｐｘ±Ｐｌ。它们是在建平变质杂岩受中元古代三座庙序列侵入岩侵位作用影响发生的相当于辉石角岩相接触热变质作用中形成的，温压条件为７２０℃～７８０℃，０．６４～０．７０ＧＰａ。这些后成合晶的结构特征、矿物学特征、变质反应前后体积变化、岩体热传导模型的时间域的半定量估算等都表明它们是在压力降低，热扰动历史较为短暂（介于２．８５Ｍａ和１１．４０Ｍａ之间）的非平衡条件下形成的     

太行山太古宙变质杂岩中富铝片麻岩的变质作用

太行山太古宙变质杂岩中富铝片麻岩主要分布在湾子岩系的底部，常常与大理岩密切伴生或者以似层状体产于花岗质片麻岩中。依据岩石结构和反应关系将变质作用分为早期、中期和晚期三个阶段。早期矿物组合为Ｇｔ（石榴石）＋Ｓｔ（十字石）＋Ｐｌ（斜长石）＋Ｍｓ（白云母）＋Ｂｉ（黑云母）＋Ｒｕ（金红石）＋Ｑｚ（石英）±Ｋ－ｆｓ（钾长石）；中期矿物组合为Ｇｔ＋Ｇｅｄ（铝直闪石）＋Ｂｉ＋Ｐｌ＋Ｉｌｍ（钛铁矿）＋Ｃｏ（刚玉）＋Ｓｉｌ１（毛发状夕线石）＋Ｑｚ＋Ｋ－ｆｓ±Ｍｓ；晚期矿物组合为Ｈｃ＋Ｋ－ｆｓ＋Ｓｉｌ２（针柱状夕线石）。矿物温度压力计和内部一致性热力学计算结果表明早期矿物组合形成于６８０℃和０．８ＧＰａ左右，刚玉、铝直闪石和毛发状夕线石组合形成于７３０℃～７５０℃和０．７ＧＰａ左右的很窄的Ｐ－Ｔ范围内，夕线石和尖晶石矿物组合的形成温度与前一组合相似或略高，压力偏低。在Ｐ－Ｔ空间上上述矿物组合的演化构成了一条近等温减压（ＩＴＤ型）的ＰＴｔ轨迹。     

日照岚山头榴辉岩的成因及演化的PTt轨迹

岚山头含柯石英榴辉岩呈透镜状构造块体产于晚元古代含霓石碱长花岗质片麻岩中，其原岩为玄武岩浆分离结晶晚期堆积的辉长岩。该榴岩曲型的共生矿物组合可划分为４个世代：（１）Ｃｐｘ１＋Ｍｕ１（ＯｒＰｈｅｎ１）＋Ｑｚ＋Ｐｌ１；（２）Ｃｐｘ２（Ｏｍ１）＋Ｇｒ１＋Ｋｙ＋Ｃｓ；（３）Ｃｐｘ３（Ｏｍ２）＋Ｇｒ２＋Ｐｈｅｎ２＋Ｋｙ＋Ｚｏ＋Ｑｚ；（４）Ｐｌ２＋Ｔｌ＋Ｍｒｇ＋Ｐｈｅｎ３＋Ｃｚｏ＋Ｑｚ。它们分别反映４个变质演     

浙西南松阳地区石榴辉石岩变质作用演化与地质意义

浙西南松阳地区的八都群中分布有一套基性变质岩:石榴辉石岩与石榴角闪岩,其变质作用演化特点目前尚不明确。根据岩相学和矿物微区化学系统研究,发现石榴角闪岩是由石榴辉石岩退变而来,而非由榴辉岩退变而来,并经历了三个变质演化阶段,分别为峰期高压麻粒岩相阶段(M1),其矿物组合为石榴石+次透辉石±钛铁矿±石英;峰后近等温减压中压麻粒岩相退变质阶段(M2),以出现典型的减压反应结构和斜方辉石+斜长石(An_(90-92))为标志;角闪岩相退变质阶段(M3),以角闪石+斜长石(An_(33-53))+钛铁矿±次透辉石±石英等退变矿物组合为特征。相平衡模拟与传统地质温压计结合限定M1期温压条件为P=11. 6～12. 5kbar,T=780～840℃,M2期温压条件为P=7. 4～8. 2kbar,T=800～880℃,M3期温压条件为P=6. 6～7. 5kbar,T=500～560℃,三个变质阶段的温压条件具有典型的顺时针近等温减压型ITD型特征,这种演化轨迹通常代表加厚下地壳快速折返地表的动力学过程,因此,该项研究对华夏地块构造作用演化的动力学过程具有重要意义。     

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