初论福建推覆构造

本文通过实例说明了福建省推覆构造是广泛发育的,根据推覆构造介入的地层特点和发育所在的层位,将推覆构造划分三种基本类型:即基底逆冲推覆构造、盖层间拆离推覆构造和盖层间逆冲推覆构造。并按类型较详细地总结了推覆构造发育的基本特点。明确指出了基底逆冲推覆构造和盖层间拆离推覆构造是福建最基本的构造类型,对福建省基本的构造特点具有重大的影响。推覆构造的形成是受同一的、继承性的由北西向南东挤压应力作用,具有间歇性、多期次的特点形成的时代,主要是印支期和燕山早期、燕山晚期又继续发生推覆,并定位予白垩纪。文中对推覆构造的发生和发展模式提出了新的认识。     

南大巴山西北段镇巴—下高川地区地质构造解析

在南大巴山西北段镇巴—下高川地区进行1∶50 000地质填图基础上,通过对地质构造现象野外的详细观测,运用持平投影的构造几何学和运动学等方法对主要断层面擦痕和断层两侧不对称褶皱枢纽以及褶皱两翼产状进行统计分析和构造解析,结合区域沉积资料和地质年代学资料,对该区构造进行构造序列分析,并探讨南大巴山构造带的变形时限、动力学机制及其演化。研究表明：南大巴山西北段镇巴—下高川地区断裂构造特征表现为高角度逆冲推覆兼有右行走滑性质的叠瓦式逆冲推覆构造;与逆冲推覆构造相关褶皱多为轴面东倾西倒的同斜褶皱和斜歪褶皱,而且由东向西褶皱紧闭程度逐渐减弱,表明逆冲推覆方向由东向西,扩展方式为前展式。该区是在印支期扬子地块与秦岭造山带全面碰撞造山作用基础上,在燕山期中—晚期整个大巴山构造系由北东向南西方向大规模的陆内造山,形成了现今的构造几何形态,其中右行走滑构造是燕山期中—晚期（J3-K2）逆冲推覆构造持续向西南推移过程中形成的。     

福建省推覆构造研究及其意义

本文主要是根据“闽西南地区推覆构造与隐伏煤田预测研究”的主要成果来写的。在概述两次研究课题取得主要成果的同时，对福建省重大基础地质有关的问题提出了新的认识。文中重点是总结了福建省推覆构造发育的特征，将推覆构造划分为两大类（逆冲推覆构造，拆离构造）和五种类型（中深层次逆冲推覆构造、浅层次逆冲推覆构造、褶皱逆冲推覆构造和拆离（滑脱）构造、褶皱拆离构造），对各类型的主要特征、分布规律、组合特征和推覆构造的发生和发展进行系统的总结，明确指出了燕山早期中深层次边冲推覆构造是福建省规模最大、对今后寻找隐伏矿产关系最密切和最重要的推覆构造，对研究我省的推覆构造具有重要意义。并结合福建省的实际，从基础地质和找矿两方面进行论述。     

幕阜山-九岭隆起侧缘逆冲推覆和滑动拆离以及山体的不对称性

由元古界组成的幕阜山—九岭隆起,横亘于萍乐坳陷与江汉坳陷之间。隆起南侧发育了一套向南逆冲于萍乐坳陷的逆冲推覆构造,北侧发育了一套向北滑向江汉坳陷的重力滑动拆离构造。两种构造系的结构和性质迥异,构成了幕阜山-九岭山体的不对称构造。两套构造统一形成于燕山期,是在不均一侧压下引起的隆起中,南侧发生逆冲、北侧发生滑动拆离的结果。     

闽西南新泉地区推覆构造特征与成矿关系

闽西南新泉地区推覆构造发育,有逆冲推覆构造和滑脱构造2种类型。逆冲推覆构造主要发生于燕山早期,推覆方向自北西西向南东东运动,该推覆构造之下隐伏有童子岩组煤矿;燕山晚期推覆构造规模小,推覆方向自西向东运动。推覆构造及运动方向与太平洋板块由东向西俯冲有关。滑脱构造见于印支期,主要构造要素有下伏系统、润滑层及滑面、滑动系统,煤系地层在滑动过程中被切失破坏,构造变得复杂,给采矿带来了难度。滑脱构造主要与印支期岩浆热隆作用有关。推覆滑脱构造对成矿具有利和弊的双重作用。连城坪上煤矿的发现及普查成果对区域地质找矿有示范作用和指导意义。     

冀中坳陷中区中生代中晚期大型拆离滑覆构造的确定

晚侏罗世至早白垩世 ,太行地区受区域热构造事件的影响 ,燕山期的岩浆活动达到高潮 ,并由此引发了阜平、赞皇变质核杂岩的强烈拱升及浅层的侧向伸展拆离作用 ,在阜平变质核杂岩东侧的冀中坳陷中区形成了西部伸展而东部挤压的有机相连、有序发展的拆离滑覆构造体系 ,波及宽度达 1 5 0km。其后缘伸展区表现为变质核杂岩内的韧性剪切带、盖层内的拆离伸展断层及伴随的断陷盆地 ;而前缘挤压区形成叠瓦状逆冲推覆构造体系 ;介于二者之间的中部过渡带构造变形相对较弱     

江西萍乡——乐平地区推覆构造

萍—乐坳陷及其基底存在不同层次的滑脱,并由宜春盆地滑覆系、九岭南缘逆冲推覆系和乐平逆冲推覆系组成一个规模宏大的复杂推覆系。推覆系内部存在三种不同的结构类型:基底逆冲叠瓦式、盆地盖层对滑式和盆岭对冲式。盖层区逆冲断层扩展的主导因素是盖层底部不整合面的拆离,后继作用是多层次滑脱和随后的切层逆冲,扩展顺序由盆内指向盆缘,即内序列。推覆作用主要导源于东秦岭中生代的陆内俯冲,分三个推覆期:印支期、燕山早期和喜马拉雅期。     

赣西北中部逆冲推覆构造的形成时间和形成模式

江西九岭地体南缘武功山地体北侧以及其间的萍乐盆地内,有大量的逆冲推覆构造分布。逆冲推覆构造的类型有两种－－逆冲推覆型和重力滑覆型。逆冲推覆构造具有横向上对冲挤压,纵向上多层滑动的特征,据此笔者建立了一个可能的多层滑动－－对冲挤压模式,并根据地质和同位素年龄资料了逆冲推覆构造的演化历史,指出区内大规模逆冲推覆构造的形成时间为中生代晚期（１１９．６Ｍａ）。     

西藏聂荣变质杂岩及邻区逆冲推覆与构造隆升时代

通过详细的野外观测结合地质填图资料,在聂荣变质杂岩及邻区厘定大规模逆冲推覆构造,不同时代的逆冲岩席自北—北东向南—南西逆冲推覆于上白垩统红层及下伏岩石地层之上,形成大量逆冲断层、滑脱构造、飞来峰、构造窗和褶皱构造。逆冲推覆构造运动导致侏罗纪蛇绿混杂岩、石炭系—二叠系构造层、古生界浅变质岩、变质基底之间发生拆离滑脱,在聂荣变质杂岩内部形成韧性剪切带和高角度斜冲断层。在唐古拉山口南侧形成北西—南东向土门-托纠-杂色右旋走滑断裂,走滑断裂末端转换为近东西向逆冲推覆构造。聂荣变质杂岩顶部逆冲推覆叠加滑覆,导致侏罗系混杂堆积和古生界沉积盖层向南西—西向运移86~110km,在那曲-巴尔达-班戈北形成近东西向长透镜状懂错蛇绿混杂岩逆冲岩席,沿缓倾斜断层发育向西倾斜的构造片理、摩擦镜面和近东西走向的矿物线理。裂变径迹测年表明,聂荣变质杂岩及邻区逆冲推覆及构造隆升时代主要为早白垩世晚期—晚白垩世早期(111±5~91±5Ma)、晚白垩世晚期(89±6~69±5Ma)、古新世晚期—始新世早期(55±4~44±2Ma),估算构造隆升视速率为0.10~0.69mm/a,部分断层逆冲推覆及构造隆升延续至古近纪晚期。综合各类观测资料,建立不同时期构造模式,探讨聂荣变质杂岩及邻区逆冲推覆构造演化过程及形成机理。     

江西南城地区中—新生代推滑覆构造研究

通过对江西南城地区侏罗系林山群与下伏前泥盆纪变质地层、白垩纪地层与前白垩纪地层接触关系调查和谢家构造窗、竺由新村构造窗、上乌石构造窗、望天石飞来峰的发现及钻孔验证,初步厘定了区内燕山期滑覆构造和喜马拉雅期推覆构造。燕山期滑覆构造发生在中侏罗世末,主滑面沿华力西—印支构造层(D—T2)、燕山构造层(T3—K1)与下伏地层间角度不整合面扩展而成,泥盆纪—早白垩世地层为滑覆体,滑覆在前泥盆纪变质地层之上,动力学来源为太平洋板块由南东向北西对欧亚板块俯冲。喜马拉雅期推覆构造规模大、动力学机制复杂(顺层和切层推覆),彻底打破了华南地区原有的地层沉积层序,形成了现存的横向分带、纵向分层的多层叠瓦、堆垛推覆构造格局。前白垩纪地质体为外来推覆体,由南东向北西推覆堆垛在白垩纪地层之上,白垩纪地层呈"构造窗"分布于前白垩纪地质体之下,动力学来源可能为印度板块与欧亚板块碰撞形成。     

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.     

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