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TAKE ANOTHER VISION TO THE UPLIFT OF THE QING—ZANG (TIBETAN) PLATEAU BASED ON CENOZOIC VOLCANISM

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地学前缘 2000年第S1期7卷 370-371页

作者： Liu Jiaqi [WT5,5”BX](institute of geology and geophysics,chinese academy of sciences,beijing 100029, china)

The emergence of the Qing—Zang plateau is among the most important geological events on the globe since the Cenozoic Era. Many geological issues can find answer from here. The major issues concerning plateau probably have three: (1) geodynamics, timing and speed of the plateau uplift;(2) The plateau uplift impact on surrounding environment;(3) mineral resources in the plateau. The authors want to focuses on first issue based on volcanisms occurred in interior and surrounding of the plateau, The new opinions are following:(1) Each volcanic eruptive episode corresponded to strong uplift stage;(2) The dynamic mechanism of the plateau uplift can not ignore another force from west beyond collision between Indian and Eurasia plates from South;(3) The surrounding volcanic chain is not only related to the collision from South, but also from west.

关键词： Tibetan plateau the Cenozoic volcanism volcanic chain surro unding plateau west collision uplift mechanism

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, china

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science china Earth sciences 2004年第2期47卷 171-180页

作者： LIU Jianming, ZHANG Hongfu, SUN Jinggui & YE Jie1. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. School of Earth science, Jilin University, Changchun 130061, china Correspondence should be addressed to Liu Jianming (email: jmliu@***) institute of geology and geophysics Chinese Academy of Sciences Beijing China School of Earth science Jilin University Changchun China

This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, china. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13C and δ18O in the range of -4.8‰--7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North china Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demonstrates that the lithospheric mantle beneath the region underwent at least twice reconstructions since the Paleozoic. Available data imply that the first reconstruction mainly happened during the Triassic-Jurassic time with gradual changes and the second in the Cretaceous with abrupt changes. Results also show that the early Cretaceous (especially at 120-130 Ma) was perhaps the key period leading to the dramatic change of the Mesozoic geodynamics on the eastern North china Craton.

关键词： mantle-derived rocks, carbonate minerals, C-O isotope, Sr-Nd isotope, lithospheric mantle, Shandong.

The deep thermal characteristic of continental margin of the northern South china Sea

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chinese science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. Graduate School, University of science and Technology of china, chinese academy of sciences, beijing 100039, china 2. institute of geology, chinese academy of sciences, beijing 100029, china Graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

SEISMIC STUDIES OF MARINE GAS HYDRATES

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化工学报 2003年第Z1期54卷 47-56页

作者： SONG Haibin (institute of geology and geophysics, CAS, beijing 100029, china) institute of geology and geophysics CAS Beijing 100029 China

We give a brief introduction of developments of seismic methods in the studies of marine gas hydrates. Then we give an example of seismic data processing for BSRs in western Nankai accretionary prism, a typical gas hydrate distribution region. Seismic data processing is proved to be important to obtain better images of BSRs distribution. Studies of velocity structure of hydrated sediments are useful for better understanding the distribution of gas hydrates. Using full waveform inversion, we successfully derived high-resolution velocity model of a double BSR in eastern Nankai Trough area. Recent survey and research show that gas hydrates occur in the marine sediments of the South china Sea and East china *** we would like to say seismic researches on gas hydrate in china are very preliminary.

关键词： gas hydrates, bottom-simulating reflector, seismic, full waveform inversion, Nankai Trough

Mid-Holocene climate change in North china, and the effect on cultural development

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chinese science Bulletin 2002年第5期47卷 408-413页

作者： JIN Guiyun & LIU Dongsheng (LIU Tungsheng)institute of Cultural Relics and Archaeology of Shandong Province, Jinan 250012, china institute of geology and geophysics, chinese academy of sciences, beijing 100029, china institute of Cultural Relics and Archaeology of Shandong Province Jinan China institute of geology and geophysics Chinese Academy of Sciences Beijing China

In this study, to reconstruct the paleoclimatic history, pollen and oxygen isotope were analyzed on the 160 samples of a 2.7 m peat core from Taishizhuang, Huailai County, Hebei Province. Combining our data with other information of climate history and archaeology from this area, we found that there is a close linkage between cultural development and the mid-Holocene (6000-3000 cal. aBP) environment changes. The main results and conclusions are presented as the following: The climate during 5678-5400 cal. aBP was unstable and in general colder and drier than today. From 5400 to 4800 cal. aBP the climate was much warmer and wetter than before. The climate during 4800-4300 cal. aBP was persistently cold, with an exceptional cold event occurring at 4600-4300 cal. aBP. This cold event was recorded at several other localities in Northern china even the Northern Hemisphere and played an important role in the cultural development. After the cold event, there was a return to warmer conditions between 4200 and

关键词： North china peat mid-Holocene cold event cultural development.

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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science china Earth sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of Mineral Resources, institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. beijing institute of geology for Mineral Resources, beijing 100012, china Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China beijing institute of geology for Mineral Resources Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North china Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Typical basin-fill sequences and basin migration in Yanshan, North china ——Response to Mesozoic tectonic transition

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science china Earth sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of geology and geophysics, chinese academy of sciences, beijing 100029, china 2. china University of Geosciences, beijing 100083, chinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) institute of geology and geophysics Chinese Academy of Sciences Beijing China china University of Geosciences Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North china may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

^(40)Ar/^(39)Ar chronology and geochemistry of high-K volcanic rocks in the Mangkang basin, Tibet

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science china Earth sciences 2005年第1期48卷 1-12页

作者： ZHANG Huihua, HE Huaiyu, WANG Jianghai & XIE Guanghong Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china institute of geology and geophysics, chinese academy of sciences, beijing 100029, china College of Life sciences, Sun Yat-Sen University, Guangzhou 510275, china chinese academy of sciences Guangzhou Institute of Geochemistry Guangzhou China chinese academy of sciences Institute of Geology and Geophysics Beijing China College of Life sciences Sun Yat-Sen University Guangzhou China

Our two newly obtained high-quality 40Ar/39Ar ages suggest that the high-K volcanic rocks of the Lawuxiang Formation in the Mangkang basin, Tibet were formed at 33.5 ( 0.2 Ma. The tracing of elemental and Pb-Sr-Nd isotopic geochemistry indicates that they were derived from an EM2 enriched mantle in continental subduction caused by transpression. Their evidently negative anomalies in HFSEs such as Nb and Ta make clear that there is an input of continental material into the mantle source. The high-K rocks at 33.5 ( 0.2 Ma in the Mangkang basin may temporally, spatially and compositionally compare with the early one of two-pulse high-K rocks in eastern Tibet distinguished by Wang J. H. Et al., implying that they were formed in the same tectonic setting.

关键词： Cenozoic high-K volcanic rocks, 40Ar/39Ar chronology, Mangkang basin, Tibet.

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

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science china Earth sciences 2007年第8期50卷 1266-1272页

作者： YAN BangLiang CMSR, institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china CMSR Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.

关键词： Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback