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Ginkgo from Lower Cretaceous Changcai Formation in Helong of Jilin, NE China

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Global Geology 2005年第Z1期 1-8页

作者： SUN Yue-wu, WANG Yu-xin, WEI Wen-yan Research Center of Palaeontology & Stratigraphy, Jilin University, changchun 130026, Jilin, China College of Earth Sciences, Jilin University, changchun 130061, Jilin, China

Based on gross morphological and cuticular study, two species of Ginkgo From the Lower Cretaceous Changcai Formation in Helong of Jilin. were identified from this area for the first time, including Ginkgo coriacea Florin and G. sibirica Heer. The study is significant for better understanding the paleophytogeographic, paleoecologic and stratigraphic characters of the Early Cretaceous Changcai flora.

关键词： Ginkgo cuticle Lower Cretaceous Changcai Formation Jilin of China

MID-PROTEROZOIC METAMORPHIC ROCKS, METAMORPHISM AND CRUSTAL EVOLUTION IN THE WEST OF LIAONING PROVINCE

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Scientia Geologica Sinica 1998年第1期 37-47页

作者： Yu Liangjun Institute of Geology, Chinese Academy of sciences, Beijing, 100029 Zhou Yuwen changchun university of science and technology, changchun, 130061 Li Jiliang Institute of Geology , Chinese Academy of sciences, Beijing, 100029

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关键词： MID-PROTEROZOIC METAMORPHIC ROCKS LIAONING OF THE EVOLUTION CRUSTAL AND

Macro-and microscopic mechanical behaviour of flow of coal samples experimentally deformed at high temperatures and pressures

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Chinese Science Bulletin 2005年第S1期50卷 59-66页

作者： LIU Junlai , YANG Guang & MA Rui State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geosciences, Beijing 100083, China College of Earth Sciences, Jilin University, changchun 130061, China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China College of Earth Sciences Jilin University Changchun China

Coal samples from Qinshui Basin, Shanxi, China are experimentally deformed at temperatures and confining pressures of 200 - 500℃and 200 - 500 Mpa, strain rate of 0.5×10-5/s and total strain of 10%. The vitrinite reflectance of the coal samples varies from 3.04 to 1.79. It is shown that the strengths of the deformed samples change obviously with coeval increasing temperatures and pressures (T/P). At the experimental range of T/P, the effects of increasing temperature predominate over that of increasing pressure. Microstructural analysis indicates a brittle to ductile transition under experimental T/P conditions from 200 to 300℃, and 200 to 300Mpa. Brittle deformation microstruc-tures include macroscopic fracture zones and penetrative fracture associations. Elongation, undulose or irregular extinction, deformation lamellae and dynamic recrystallization of grains are the main ductile deformation microstructures. The variation of deformation mechanisms of the experimentally deformed coal samples is related to both the components of coals and T/P conditions. At low T/P, fractures occur in both inertinite and vitrinite of the samples. At higher T/P, crystalline plastic deformations are observed in the inertinite only.

关键词： coal experimental deformation brittle to ductile transition.

A Simple Shear Model for the Asymmetry in the Paleoproterozoic Fold Belt in Liaodong Peninsula

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Global Geology 2001年第1期6卷 26-33页

作者： Cui Yingchun, Liu Junlai, Ma Lijie and Guan Huimei (Dept. Earth Sci., Jilin University, changchun 130061 P.R. China) Dept. Earth Sci. Jilin University Changchun 130061 P.R. China

Several aspects of the Liaodong Paleoproterozioc fold belt, including its components, tectonic, metamorphic and magmatic characteristics are discussed in the paper, with emphasis on the asymmetry of the fold belt and differences between the northern lineal-fold belt and the southern dome-fold belt. It is suggested that the fold belt is one magmatic passive margin, instead of a rift zone or the classical passive continental margin. The formation and evolution of the fold belt is dis- cussed with a simple shear model, which may best explain the co-existence of contemporaneous tectonic facies with different characteristics, the volcanic and plutonic activities, sedimentary formations and their geological attributes etc.

关键词： Liaodong, differentiation, magmatic passive continental margin, simple shear model

SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science China Earth Sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2 & SU Li3 1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 College of Earth Sciences, Jilin University, changchun 130061, China 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources, China University of Geo- sciences, Beijing 100083, China Institute of Geology Chinese Academy of Geological Sciences Beijing China College of Earth Sciences Jilin University Changchun China The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

PERIODIC SOLUTIONS FOR A DISCRETE TIME RATIO-DEPENDENT TWO PREDATOR-ONE PREY SYSTEM

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Annals of Differential Equations 2004年第1期20卷 1-13页

作者：柏灵范猛王克 Institute of Math. Science Jilin University Changchun 130061 Dept. of Math. Northeast Normal University Changchun 130024

In this paper, we consider a three-species ratio-dependent predator-prey model governed by difference equations with periodic coefficients. By using the method of coincidence degree, we discuss the existence of positi... 详细信息

关键词： ratio-dependent predator-prey system positive periodic solution difference equation coincidence degree

ROCK－FORMING　MINERALS　AND　ORE－FORMING　MINERALS　OF　DASHUIGOU　TELLURIUM　ORE　DEPOSIT　UNIQUE　IN　THE　WORLD－A　PRELIMINARY　STUDY

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Scientia Geologica Sinica 1994年第2期 197-210页

作者： Yin Jianzhao Zhou Jianxiong and Mao Jingwen(Chinese Academy of Geological Sciences, Beijing 100037)Yang Baichuan(Nonferrous Rare and Precious Metals Company of Sichuan Province,Chengdu 610036)Zhang Yuan(changchun College of Geology, changchun 130061)

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关键词： ORE FORMING ROCK AND

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.

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浅论会计计量属性

吉林省经济管理干部学院学报 2003年第2期17卷 47-48页

作者：孙英长春税务学院会计系吉林长春130021

FASB在财务会计概念公告(SFAC5)“企业财务报表项目的确认和计量”中介绍了五种计量属性。但在我国现有的法律体系和弱式有效市场务件下,仍应以历史成本为主要计量属性,以防止人为操纵利润。

关键词：会计计量历史成本现行成本 FASB 财务会计企业利润操纵