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Chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU MeifuInstitute of geology and geophysics, Chinese Academy of Sciences, Beijing 100029, China Key Laboratory of Mineral Resources, Institute of geology and geophysics, Chinese Academy of Sciences, Beijing 100101, China department Institute of geology and geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China department of Earth Sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

Oroclinal bending and block rotations in South China since the Mesozoic——Geological and paleomagnetic evidence

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Chinese Science Bulletin 1997年第2期42卷 132-136页

作者： LI Zhengxiang, FANG Dajun, Christopher McA. Powell and LOU Gang1. department of geology and geophysics, The University of Western Australia, Nedlands WA 6907, Australia 2. department of Earth Sciences, Zhejiang University, Hangzhou 310027, China department of geology and geophysics The University of Western Australia Nedlands Australia department of Earth Sciences Zhejiang University Hangzhou China

THE South China Block exhibits a complex structural pattern in its Neoproterozoic-Mesozoic sedimentary cover. The lack of knowledge about the formation of this pattern hinders our understanding of the regional tectonic evolution and paleogeography, and the reconstruction of Phanerozoic apparent polar wander path(s). In this note we present a synthesis based on a paleomagnetic and tectonic analysis, which suggests that (i) the structural pattern over

关键词： Mesozoic paleomagnetism block rotation.

Garnet-Spinel Transition in the Upper Mantle: Review and Interpretation

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Journal of Earth Science 2010年第5期21卷 635-640页

作者：苏本勋张宏福 Sakyi Patrick Asamoah 秦克章汤艳杰英基丰肖燕 Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences department of Earth Science University of Ghana Legon-Accra Ghana

This study carried out a comprehensive review of mantle-derived garnet peridotites on the basis of their garnet-spinel compositional relationships. The P-T estimates of the garnet peridotites of both orogenic and xenolithic derivations confirm previously established two garnet-spinel transition （GST） zones. Results of natural samples and experimental studies of all the garnet peridotites plot below the first GST at low P （〈2 GPa）. The second GST at high P （6-10 GPa）, obtained from the experimental system （MgO-Cr203-SiO2）, was firstly evidenced from natural samples in this study and may imply a challenge to our understanding of Cr-rich and Al-poor mineral phase transition under ultrahigh P condition. Based on the data and our estimates, we propose the existence of another GST within the garnet peridotite discontinuous zone and a potential spinel-phase peridotite zone in the upper mantle.

关键词： garnet peridotite garnet-spinel transition spinel peridotite ultra-high P-T upper mantle.

Precise dating of East-Asian-Monsoon D/O events during 95―56 ka BP:Based on stalagmite data from Shanbao Cave at Shennongjia,China

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Science China Earth Sciences 2007年第2期50卷 228-235页

作者： XIA ZhiFeng KONG XingGong JIANG XiuYang CHENG Hai College of Geographic Science Nanjing Normal UniversityNanjing 210097China department of geology and geophysics University of MinnesotaMN 55455USA

Based on 23 U/Th analyses and 532 oxygen isotopic data, an averaged 80-a stalagmite oxygen isotopic composition series was established through 95 to 56 thousand years before present (ka BP) from two speleothems in Shanbao Cave, Shennongjia, central China. Shanbao Cave record (referred to as SB record) replicates well with Hulu Cave record, extending the characteristics of millennial oscillations in East-Asian-Summer-Monsoon (EASM) to the past 95 ka. The trend of the SB record generally follows mid-July solar insolation at 65°N, suggesting that mid-high northern latitude insolation, in the first or- der, controls changes of EASM intensity. Millennial oscillations of EASM recorded in the stalagmites are well related to the Greenland interstadials referred to as Dansgaard/Oeschger (D/O) events from 1 to 22, indicating that rapid ocean-atmosphere reorganization in North Atlantic has a remote effect in EASM. The well-dated D/O events by stalagmites probably provide an absolute calibration for chro- nologies of Greenland ice cores. The timings of D/O events in the SB record are different variously from those in Greenland ice cores. For D/O 19 and 20, the age offsets between the stalagmites' and the Greenland ice cores' record are significant, larger than the uncertainties of uranium-series dating. The two events in the SB record are younger than those in North GRIP time scale by 1―2 ka, and older than the counterparts in GISP2 by approximately 3―4 ka. A comparison between the SB and Brazil stalag- mite record shows an anti-phase relation in millennial-scale monsoon precipitation between the two localities. This supports a mode for the coupled ocean-atmosphere "See-saw".

关键词： the last glacial Shennongjia stalagmite Greenland ice cores timing of D/O event

Structure of the crust and uppermost mantle from broadband seismic array in the western Dabie Mountains,east central China

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Science China Earth Sciences 2009年第2期52卷 203-212页

作者： LI Hua WANG LiangShu LI Cheng LIU FuTian HU DeZhao YU DaYong department of Earth Sciences Nanjing UniversityNanjing 210093China Institute of geology and geophysics Chinese Academy of SciencesBeijing 100029China

A broadband seismic array of 7 stations was set up in the western Dabie Mountains (31°20′-31°50′N, 114°30′-115°E). Teleseismic events from May 2001 to November 2001 were collected and analyzed by radial receiver function to determine the S-wave velocity structure of the crust and uppermost mantle. The crustal thickness is 32-38 km beneath the array. The crust-mantle boundary appears as a gently north-dipping velocity discontinuity, but turns to be a velocity gradient beneath a station near the Qiliping shear zone in the south of the array. In the north of the array, a large offset of 4-6 km exists in the Moho along the Tongbai-Tongcheng shear zone, suggesting a suture zone formed by the northward subduction of the Yangtze plate beneath the North China plate. Along the Tongbai-Tongcheng shear zone, a north-dipping, EW-striking low-velocity zone was observed in the upper mantle, which may be related to the collision boundary between the Yangtze and the North China plates in the Triassic. Therefore the Tongbai-Tongcheng shear zone is the southern boundary of suture zone between the Yangtze and the North China plates. In the south of the array, a high-velocity body in the lower crust near the Qiliping shear zone probably results from the underplate of mafic magma into the lower crust, which is generally associated with large-scale extension triggered by delamination of the thickened crust.

关键词： Dabie Mountains receiver functions S-wave velocity lithosphere structure

Experimental Investigation of the Creep Behavior of Garnet at High Temperatures and Pressures

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Journal of Earth Science 2010年第5期21卷 532-540页

作者： Shenghua Mei Ayako M Suzuki David L Kohlstedt 许丽丽 department of geology and geophysics University of Minnesota MN 55455 USA Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

To provide constraints on the rheological properties of garnet, we have experimentally investigated the creep behavior of garnet at high pressures and temperatures using a deformation-DIA. Samples were cold-pressed from a garnet powder and deformed at constant displacement rates ranging from 1.1×10^-5 to 2.6×10^- s^-1 at high temperatures （1 273-1 473 K） and high pressures （2.4-4.1 GPa）. Differential stress and pressure were measured using X-ray diffraction techniques based on the elastic strain of various lattice planes as a function of orientation with respect to the applied stress field. The plastic strain of a deforming sample was monitored in-situ through a series of radiographs. Our results provide a measure of the dependence of creep rate of garnet on the temperature with an activation energy of -280 kJ/mol and on pressure with an activation volume of -10×10^-6 m3/mol. The flow behavior of garnet quantified by this study provides the basis for modeling geodynamic processes occurring within subducted lithosphere.

关键词： garnet creep lithosphere geodynamics high pressure.

RIVERINE SEDIMENTS AND CHINESE COASTLINE CHANGES

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Chinese Geographical Science 1997年第3期7卷 201-207页

作者：李从先张桂甲 department of Marine geology and geophysics Tongji University Shanghai P. R. China

The tectonic uplifting and depression in the coastal zones results in the anormal distribution of riverine sediments. The coastal zones of tectonic depression areas received about 95% of the riveine sediments, whereas the tectonic uplift belts received only 5% of that, which is the main reason for the variety of the coastline types and the changes in the coastline. On the basis of this anormal distribution of riverine sediments in Chinese coastline, this paper discusses the scope and time of the maximum transgression, the trend, rate and period of the coastline changes, and the impact of riverine sediments on the future changes in coastline.

关键词： coastline coastal environment riverine sediments sea level rise

The evolution of refertilized lithospheric mantle beneath the northeastern Siberian craton:Links between mantle metasomatism,thermal state and diamond potential

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Geoscience Frontiers 2022年第6期13卷 153-169页

作者： Sergei Skuzovatov Vladislav S.Shatsky Alexey L.Ragozin Alexander P.Smelov Vinogradov Institute of Geochemistry Russian Academy of SciencesSiberian Branch1AFavorskogo Str.Irkutsk 664033Russia Sobolev Institute of geology and Mineralogy Russian Academy of SciencesSiberian Branch3Koptyug Ave.Novosibirsk 630090Russia geology&geophysics department Novosibirsk State University2 Pirogova Str.Novosibirsk 630090Russia Diamond and Precious Metal geology Institute Russian Academy of SciencesSiberian Branch39Lenina Ave.Yakutsk 677000Russia

Although the diamond potential of cratons is linked mainly to thick and depleted Archean lithospheric keels, there are examples of craton-edge locations and circum-cratonic Proterozoic terranes underlain by diamondiferous mantle. Here, we use the results of comprehensive major and trace-element studies of detrital garnets from diamond-rich Late Triassic(Carnian) sedimentary rocks in the northeastern Siberia to constrain the thermal and chemical state of the pre-Triassic mantle and its ability to sustain the diamond storage. The studied detrital mantle-derived garnets are dominated by low-to mediumCr lherzolitic(~45%) and low-Cr megacrystic(~39%) chemistries, with a significant proportion of eclogitic garnets(~11%), and only subordinate contribution from harzburgitic garnets(~5%) with variable CrOcontents(1.2–8.4 wt.%). Low-Cr megacrysts display uniform, “normal” rare-earth element(REE)patterns with no Eu/Eu* anomalies, systematic Zr and Ti enrichment(mainly within 2.5–5), which are evidence of their crystallization from deep metasomatic melts. Lherzolitic(G9) garnets exhibit normal or humped to MREE-depleted sinusoidal REE patterns and elevated Nd/Y(up to 0.33–0.41) and Zr/Y ratios(up to 7.62). Rare low-to high-Cr harzburgitic(G10) garnets have primarily “depleted”, sinusoidal REEpatterns, low Ti, Y and HREE, but vary significantly in Zr-Hf, Ti and MREE-HREE contents, Nd/Y(within 0.1–2.4) and Zr/Y(1.53–19.9) ratios. The observed trends of chemical enrichment from the most depleted,harzburgitic garnets towards lherzolitic(including high-Ti high-Cr G11-type) garnets and megacrysts result from either voluminous high-temperature metasomatism by plume-derived silicate melts or recurrent mobilization of less voluminous kimberlitic or related carbonated mantle melts, rather than the initially primitive, fertile nature of the Proterozoic SCLM. Calculated Ni-in-garnet temperatures(primarily within ~1150–1250 ℃) indicate their derivation from at least ~220 km thick Cr-undersa

关键词： Siberian craton Kimberlite Diamond placers Peridotites Eclogites Megacrysts

Test of Deep Seismic Reflection Profiling across Central Uplift of Qiangtang Terrane in Tibetan Plateau

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Journal of China University of Geosciences 2009年第2期20卷 438-447页

作者：卢占武高锐李秋生贺日政匡朝阳侯贺晟熊小松管烨王海燕 Klemperer S L Lithosphere Research Centre Institute of GeologyKey Laboratory of Earthprobe and GeodynamicsChinese Acdemy of Geological Sciences department of geophysics Stanford University

A test of deep seismic reflection profiling across the central uplift or metamorphic belt of the Qiangtang （羌塘） terrane, Tibet plateau, provides a first image of the crustal structure. Complex reflection patterns in the upper crust are interpreted as a series of folds and thrusts, and bivergent reflections in the lower crust may represent a convergence between the Indian and the Eurasian plates.

关键词： Qiangtang terrane central uplift zone crustal structure test of deep reflection profiling,convergent process.

Hour-to-hour variability of the ionosphere: An application of the classical multidimensional scaling method

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Science China Earth Sciences 2015年第7期58卷 1243-1250页

作者： SHI Hao ZHANG DongHe HAO YongQiang XIAO Zuo department of geophysics Peking University

The classical multidimensional scaling(MDS) method is introduced and applied in the study of the hour-to-hour ionospheric variability based on the ionospheric fo F2 observed at three ionosonde stations in East-Asia in 2002 and 2007. Results from the matrix eigen decompositions indicate that the annual part of the ionospheric variation is large in middle latitude and solar maximum period(2002) while low in the low latitude and solar minimum period(2007). The connectivity maps of the hour-to-hour ionospheric variability based on MDS method show some common diurnal features. The ionospheric connectivity between adjacent hours near noon hours and near midnight hours is high. The ionospheric connectivity between adjacent hours near sunrise hours and near sunset hours is poor, especially for the sunrise hours. Also there are latitudinal and solar activity dependences in this kind of connectivity. These results revealed from the ionospheric connectivity maps are useful physically and in practice for the ionospheric forecasting on the hour-to-hour scale.

关键词： ionospheric variability classical multidimensional scaling connectivity map