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Acta Geologica Sinica(English Edition) 1993年第4期67卷 465-476页

作者： department of earth sciences, NSFC

Geostrophic Wave Circulations(English edition)

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Advances in Atmospheric sciences 1995年第2期12卷 259-260页

作者： Yong L.McHall(Dept.of earth,Atmospheric and planetary sciences,MITPublished by china Meteorological Press) Dept. of earth Atmospheric and Planetary Sciences MIT Published by China Meteorological Press USA

Abstract

关键词： Wave English edition Geostrophic Wave Circulations

Almandine megacrysts from Yingfengling Cenozoic basalt in Leizhou Peninsula and their parental magma origin

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Chinese Science Bulletin 2001年第14期46卷 1215-1219页

作者： YU Jinhai & S. Y. O’Reilly1. National Key Laboratory of Metallogenic Mechanism of Endogenetic Deposits, department of earth sciences, Nanjing University, Nanjing 210093, china 2. National Key Center of GEMOC, department of earth and planetary sciences, Macquarie University, North Ryde, NSW 2109, Australia National Key Laboratory of Metallogenic Mechanism of Endogenetic Deposits Department of Earth Sciences Nanjing University Nanjing China National Key Center of GEMOC Department of Earth and Planetary Sciences Macquarie University North Ryde Australia

The garnet megacrysts from Yingfengling basalts are characterlzed by high FeO (>20%), CaO (7.02% -8.16%) and low MgO (5.88%-10.87%). Significant composition variations are observed in these megacrysts, of which Ni, V, Sc, Co, and HREE are positively correlated with their Mg# and Zr, Hf, Ga, Y, Sr, Nb, Zn and LREE-MREE are negatively correlated with Mg#. Megacryst parent magma is a highly evolved residual melt with strongl depletion in Ti, Sr, Hf, Nb and HREE. This parental magma was generated by more than 60% of crystallization fractionation of clinopyroxene, garnet, plagioclase and ilmenite from quartz tholeiitic magma. It has not erupted to the surface, but stayed at the upper mantle and formed the megacrystic cumulate. Megacrysts and their host basalt are in disequilibrium.

关键词： almandine megacryst geochemistry LAM-ICPMS Lei-zhou Peninsula.

Garnet-bearing Granulite Facies Rock Xenoliths from Late Mesozoic Volcaniclastic Breccia, Xinyang, Henan Province

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 445-451页

作者： ZHENG Jianping, SUN Min, LU Fengxiang, WANG Chunyangand ZHONG Zengqiu Faculty of earth sciences, china University of Geosciences, Wuhan 430074, china department of earth sciences, The University of Hong Kong, china Faculty of earth sciences China University of Geosciences Wuhan 430074 China department of earth sciences The University of Hong Kong China [?]3Zheng Jianping Born in 1964 graduated from the china University of Geosciences (Wuhan) with a PhD degree in 1997 mainly engaged in teaching and scientific researches on petrology and chemical geodynamics. E-mail: jpzheng@***.

This paper presents the primary results of petrologic, mineralogical and petrochemical studies of garnet-bearing granulite facies rock xenoliths from Xinyang, Henan Province. These xenoliths, which are found in a pipe of late Mesozoic volcaniclastic breccia, are of high density (3.13–3.30 g/cm3) and high seismic velocity (Vp = 7.04–7.31 km/s), being products of underplating of basaltic magmas and had experienced granulite facies metamorphism. The underplating and metamorphism took place before the eruption of the host rock. Petrographical studies and equilibrium T-P calculations show that these xenoliths were captured at a 49 km depth and experienced at least a 16 km uplift before they were captured. The dynamics of the uplift could be related to the continent-continent collision between the North china plate and the Yangtze plate during the Triassic.

关键词： granulite facies mafic rock xenolith uplift Xinyang

^(40)Ar-^(39)Ar and U-Pb ages of metadiorite from the East Kunlun Orogenic Belt: Evidence for Early-Paleozoic magmatic zone and excess argon in amphibole minerals

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Chinese Science Bulletin 2001年第4期46卷 330-333页

作者： CHEN Nengsong, SUN Min, ZHANG Kexin & ZHU YunhaiFaculty of earth sciences, china University of Geosciences, Wuhan 430074, china department of earth sciences, The University of Hong Kong, Hong Kong SAR, china Faculty of earth sciences China University of Geosciences Wuhan China department of earth sciences The University of Hong Kong Hong Kong SAR China

Single-grain zircon U-Pb and amphibole 40Ar-39Ar dating have been conducted on a deformed and metamorphosed diorite in the East Kunlun Orogenic Belt, which intruded into the middle Proterozoic Kuhai Group exposed in the south of Xiangride region, Dulan County, NW Qinghai Province. The zircon gives a concordant U-Pb age of (446.5±9.1) Ma. The amphibole yields Ar plateau age of (488.0±1.2) Ma and an isochronal age of (488.9±5.6) Ma. Age results of both stepwise released Ar and conventional K-Ar analysis are remarkably higher than that of zircon U-Pb, suggesting that the amphibole contains excess argon and the amphibole plateau age cannot be taken as the timing of metamorphism or deformation. The zircon age is interpreted to be crystallization age of the diorite pluton, which suggests that an Early-Paleozoic magmatic zone indeed existed in the East Kunlun Orogenic Belt stretching along the region south to the Golmud, Normuhong and Xiangride.

关键词： East Kunlun Orogenic Belt metadiorite geochronology excess argon.

DISCOVERY OF THE OLIGO-MIOCENE RODENTS FROM WEST JAPAN AND THEIR GEOLOGICAL ANDPALEONTOLOGICAL SIGNIFICANCE

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古脊椎动物学报(中英文） 1995年第4期 320-329页

作者： TAKAFUMI KATO(department of earth and planetary sciences, Kyushu University, Fukuoka 812-81,Japan)HIROYUKI OTSUKA(Institute of earth sciences, Faculty of science, Kagoshima University, Kagoshima 890, Japan)

New rodent fossils found in the Oligo-Miocene sedboents in Kyushu, West Japan, are identified to the following four taxa: 1) Castoridae gen. et sp. indet. A, 2) Steneofiber sp. from the Late Oligocene Sasebo Group; 3) Castoridae gen. et sp. indet. B; 4) Diatomys shantungensis from the Early to Middle Miocene Nojdria Group. Studies of two specimens identified to the family Chstoridae gen. et sp. indet. A and B indicate that they are large beavcrs with the skull of nearly same sise as Trogontherium that holds enamel of longitudinally grooved indsors. Resemblance in sise and features of the incisor enamel indicates that these specimens could be of the same genus. Furthermore, it is known that Steneofiber is a cosmopolitan genus, however, it has not been found in the Late Oligocene in East Asia. The occurrence of Diatomys shantungensis, on the other hand, strongly suggests that the late Early Miocene mammls from Japan and the East *** to the same faunal province in Easl Asian margin.

关键词： Kyushu Japan Late Oligocene-Early Miocene Rodents

Depth zonation of Arenigian acritarchs in South china

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Chinese Science Bulletin 1997年第3期42卷 248-251页

作者： XU Wanhongdepartment of earth sciences, Nanjing University, Nanjing 210093, china department of earth sciences Nanjing University Nanjing China

STAPLIN revealed that palaeoenvironment changes seem to control acritarch distribution patterns. However, scientists have been puzzled by the fact that characteristic offshore acritarchs occur with nearshore ones. This note demonstrates depth zonation of Arenigian acritarchs in South china and reveals the variation of water depth in South china during the Arenig Age.

关键词： South china Arenigian acritarch depth zonation.

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3 1 department of earth sciences, Durham University, Durham DH1 3LE, UK 2 School of earth sciences and Resources, china University of Geosciences, Beijing 100083, china 3 School of earth and Space sciences, Peking University, Beijing 100871, china department of earth sciences Durham University Durham DH1 3LE UK School of earth sciences and Resources China University of Geosciences Beijing 100083 China School of earth and Space sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3) assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

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Progress in Natural Science:Materials International 2007年第5期17卷 551-558页

作者： Jia Dong, Chen Zhuxin, Luo Liang, Hu Qianwei and Jia Qiupeng (department of earth sciences, Nanjing University, Nanjing 210093, china) [a]department of earth sciences Nanjing University Nanjing China

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 224 oriented specimens have been drilled at 23 different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2) an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.

关键词： magnetic fabric finite strain fault-related fold trishear zone Longmenshan.