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Relativistic electron flux enhancement at synchronous orbit during SEP event.on July 14,2000

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Science China Earth Sciences 2002年第5期45卷 399-408页

作者：赵华朱光武王世金高玉芬刘振兴 Space Weather Research Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China

Relativistic (E >1.6 MeV) electron flux enhancements during Solar Energetic Particle (SEP) event. as observed by the synchronous FY-2 satellite at orbit located at 105°E are investigated. Energetic protons during SEP event. heavily contaminate relativistic electron flux measurements. The ratio of the contamination in the original measurement of relativistic electron flux was over 30% during most of the SEP event.on July 14, 2000. A method has been developed to eliminate the contamination caused by the energetic protons, and a 'corrected' relativistic electron flux has been obtained. The 'cleaned-up' relativistic electron flux measurement shows that relativistic electron flux enhancement at synchronous orbit is well correlated with SEP event. during which the IMF Bz has some southward periods. The enhancement could arise as the transport of relativistic electrons from the upstream solar wind into synchronous orbit via the magnetotail.

关键词： synchronous orbit, relativistic electron flux, solar energetic particle event.

Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, China

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Science China Earth Sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Key Laboratory for Mineral Resources Research, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Chu Xuelei (email: xlchu@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory for Mineral Resources Research Chinese Academy of Sciences Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜1300 Ma may signify two correlative global tectonic event..

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

Ordovician chitinozoan diversification event. in China

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Science China Earth Sciences 2004年第10期47卷 874-879页

作者： WANG Xiaofeng CHEN Xiaohong Center for Stratigraphy and Palaeontology CGS Yichang 443003 China Center for Stratigraphy and Palaeontology CGS Yichang 443003 China

Correlative study of the Ordovician chitinozoan biostratigraphy in China with grap- tolite and conodont biozones, and comprehensive analysis of the sequence- and event.strati- graphic indicated that 17 chitinozoan zones and 5 main chitinozoan diversification event. subsequently occurring could be recognized in the Ordovician System of China. The 5 event. comprise: event.1 — appearance of the earliest Ordovician chitinozoans, event.2 —appearance of C. symmetrica, event.3 —juvenile radiation of chitinozoans, event.4 —appearance of chitinozoans with high diversity, and event.5 —development of chitinozoans of deep-water facies. The age and feature of each event.and its relation with the sea-level change and other geological event.are discussed.

关键词： chitinozoan, Ordovician, diversification event.

Age distribution of the fauna 5.3 Ma B. P. and climatic deterioration event. in North China

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Chinese Science Bulletin 1997年第21期42卷 1826-1829页

作者： Zhang, YX Chen, DL Xue, XX NW Univ Xian Dept Geol Inst Cenozoic Geol & Environm Xian 710069 Peoples R China

THE climatic deterioration is an important event.in the geological history and generally recog-nized by composition of strata and variation in some elements. However, the study on the cli-matic deterioration event. in terms of age distribution of animals has been rarely *** note reports the study on a climatic deterioration event.and its affected area during theMiocene Epoch based on thousands of fossils of Hipparion fauna from Longjiagou in Wudu,

关键词： Hipparion fauna taphonomy climatic event.

The 1997-1998 warm event.in the South China Sea

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Chinese Science Bulletin 2002年第14期47卷 1221-1227页

作者： WANG Dongxiao XIE Qiang DU Yan WANG Weiqiang CHEN Ju Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China College of Marine Environment Ocean University of Qingdao

A strong warm event.happens during spring 1997 to spring 1999 in the South China Sea. Its intensity and duration show that it is the strongest event.on the record over the past decades. It also corresponds with the severe flood over the valley of the Yangtze River and a couple of marine environmental event.. This note addressed the evolution process by using several data sets, such as sea surface temperature, height and wind stress in addition to subsurface temperature. The onset of the warm event.almost tele-connects with the El Nino event.in the tropical Pacific Ocean. Summer monsoon is stronger and winter monsoon is weaker in 1997 so that there are persistent westerly anomalies in the South China Sea. During the development phase, the warm advection caused by southerly anomalies is the major factor while the adjustment of the thermocline is not obvious. Subsequently, the southerly anomalies decay and even northerly anomalies appear in the summer of 1998 resulting from the weaker than normal summer

关键词： South China Sea advection mode downwelling mode prolonged warm event.

Link between the geomagnetic polarity reversal and global-geology event.

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Chinese Science Bulletin 1999年第20期44卷 1843-1851页

作者： Rixiang Zhu Qingsong Liu Yongxin Pan Chinese Acad Sci Inst Geophys Beijing 100101 Peoples R China

The origin of the earth’s magnetic field is one of the five most important unsolved problems in physics, especially geomagnetic polarity reversal remains one of Nature’s most enigmatic phenomena. It is proposed that the geomagnetic polarity reversal links with some global-geology event., although it is difficult to clarify the mechanism of this correlation. The history of continental structures in eastern China would be also linked with some global-geology event..

关键词： geomagnetic reversal paleointensity global-geology event.

Premonitory phenomenon of El Nino event.reflected in the observations of LOD and sea level

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Chinese Science Bulletin 2000年第24期45卷 2231-2236页

作者： ZHENG Dawei DING Xiaoli ZHOU Yonghong CHEN Yongqi LI Zhilin LIAO Xinhao Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Center of National Astronomical Observation Chinese Academy of SciencesBeijing 100012China Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic UniversityHung HornKowloonHong KongChina

Data sets of the changes of the length of day, the sea surface temperature in the eastern Pacific and of the sea level in Hong Long from tide gauge observations are used to analyze and reveal the reflections in the observations of the length of day and the sea level changes concerned with the premonitory phenomenon of next El Nino event. The results from this study indicate that a new El Nino event.has been brewing with the ending of the strong La Nina event.that started in early summer of 1998. The estimated formation period of the new El Nino event.will begin before the end of 2000, and the peak period may be reached at around the end of 2001.

关键词： change of the length of day sea level change El Nino event.

Pedosedimentary event. in loess of China and Quaternary climatic cycles

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Chinese Science Bulletin 1996年第14期41卷 1189-1193页

作者：郭正堂丁仲礼刘东生 Institute of Geology Chinese Academy of Sciences Beijing 100029 China

In the Loess Plateau of China, the orbitally induced climatic oscillations are generally expressed by alternation of pedogenetic and sedimentary event. (pedosedimentary event.). In the last years, investigations at different localities revealed that complete loess-soil sequences contain 37 major soil stratigraphic units which are spatially correlativ. Recent studies have demonstrated that many of these soil units are polygenetic (polycyclic), which were formed by several pedogenetic stages interrupted by dust deposition stages, evidencing climatic oscillations within the interglacial periods. Some loess units contain also clearly ex-

关键词： loess-paleosol sequence polycyclic soil pedosedimentary event.

Millennial-scale paleoceanography in Okinawa Trough during Late Quaternary period

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Chinese Science Bulletin 1999年第18期44卷 1705-1709页

作者： F. Guichard G. Floch Centre des Faibles Radioactivites FranceFrench Oceanographic Institute IFREMER France

Based on the analyses of foraminifer and accelerator mass spectrometer radiocarbon dating in DGKS9603 core from mid-Okinawa Trough close to bottom, oscillation curve, which expressed the relation between the surface water temperature and the depth, has been obtained by using foraminifer analysis and calculation of FP-12E transfer function. The whole core indicated seven cold phases and eight warm phases. Obvious expression of low

关键词： Okinawa Though Late Quaternary period paleoceanograph Heinrich event.