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Megaripples from the Mesoproterozoic of the Kimberley region,northwestern Australia and its geological implications

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Journal of Palaeogeography 2012年第1期1卷 15-25页

作者： Lan Zhongwu 1,2,3,,Zhong-Qiang Chen 2,4.1.State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese {4. of Sciences,Beijing 10002.,china 2.School of Earth and Environment,The University of Western Australia,Australia 3.Key Lab of Petroleum Resources Research,institute of geology and geophysics,chinese {4. of Sciences,Beijing 10002.,china 4.State Key Laboratory of Biogeology and Environmental geology,china University of Geosciences (Wuhan),Wuhan 4.0074.china State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Earth and Environment The University of Western Australia Key Lab of Petroleum Resources Research Institute of Geology and Geoph

Large ripples are described from the Mesoproterozoic Hilfordy Formation in the Kimberley region,northwestern *** ripple index (RI) and ripple symmetry index (RSI) suggest the Kimberley ripples were likely generated by storm *** wave height is up to 15 23 cm and wave length is up to 70 90 *** features,incorporated with other morphological characteristics such as symmetry,steepness,ripple spacing,and compositions,agree well with the megaripples previously reported from the intertidal-nearshore settings of modern seas and the geological *** Mesoproterozoic ripples were likely generated by the storm-induced *** survey of the global record of megaripples reveals that such structures have occurred through the geological past from the Archean to present *** were particularly common in the Neoproterozoic and had the largest ripple length and ripple height among the modern and geological *** is probably because extreme storms prevailed at that *** frequent occurrence in present day beach is probably due to the prevalence of extreme storms caused by the monsoon or tsunami/earthquake influenced climatic regimes.

关键词： megaripples palaeohydrodynamics extreme storms Mesoproterozoic Hilfordy Formation Kimberley northwestern Australia

Gas formation mechanism of marine carbonate source rocks in china

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Science china Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2, ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4.& QIN Yong5 1. Research institute of Petroleum Exploration & Development, Petrochina, Beijing 100083, china 2. Petrochina Exploration & Production, Beijing 100011, china 3. Department of geology, Lanzhou University, Lanzhou 730000, china 4. Guangzhou Geochemical institute, chinese academy of Sciences, Guangzhou 51064., china 5. china University of Mining and Technology, Xuzhou 221000, china 1. Research institute of Petroleum Exploration & Development 100083 PetroChinaBeijin China 2. Petrochina Exploration & Production 100011 Beijing China 3. Department of geology Lanzhou University 730000 Lanzhou China 4. Guangzhou Geochemical institute Chinese Academy of Sciences 510640 Guangzhou China 5. china University of Mining and Technology 221000 Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

Principles and methods of quantitative analysis on b-axis disorder in 2 : 1 dioctahedral phyllosilicate

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chinese Science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese academy of Sciences, Changsha 4.0013.{4. 2. institute of geology, chinese academy of Sciences, Beijing 10002.,{4. Changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3n) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3n) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.

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 {4. of Sciences, Beijing 10002., china 2. Key Laboratory for Mineral Resources Research, chinese {4. of Sciences, Beijing 10002., china Correspondence should be addressed to Chu Xuelei (email: xlchu@***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China 2. Key Laboratory for Mineral Resources Research Chinese Academy of Sciences 100029 Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13. 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 δ13. 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 δ13. value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13. value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜13.0 Ma may signify two correlative global tectonic events.

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

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3 1 State Key Laboratory of Loess and Quaternary geology (SKLLQG),institute of Earth Environment,chinese academy of Sciences,Xi’an 710075,{4. 2 Graduate University of chinese academy of Sciences,Beijing 10004.,{4. 3 Key Laboratory of Cenozoic geology and Environment,institute of geology and geophysics,chinese academy of Sciences,Beijing {14.,{4. State Key Laboratory of Loess and Quaternary geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Graduate University of chinese academy of Sciences Beijing 100049 China Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4.Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern china during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积

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 {4. of Sciences, Beijing 10002., china 2. Beijing institute of geology for Mineral Resources, Beijing 100012, china Correspondence should be addressed to Wang Lijuan (email: wlj@***) 1. Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Beijing institute of geology for Mineral Resources 100012 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.

DMTB:A comprehensive online resource of 16S rRNA genes,ecological metadata,oligonucleotides,and magnetic properties of magnetotactic bacteria

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chinese Science Bulletin 2011年第6期56卷 476-478页

作者： LIN Wei1,2, LI Bi1,2 & PAN YongXin1,2 1 Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth’s Deep Interior, institute of geology and geophysics, chinese {4. of Sciences, Beijing 10002., china 2 France-china Bio-Mineralization and Nano-Structures Laboratory, institute of geology and geophysics, chinese {4. of Sciences, Beijing 10002., china Paleomagnetism and Geochronology Laboratory Key Laboratory of the Earth"s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences France-china Bio-Mineralization and Nano-Structures Laboratory Institute of Geology and Geophysics

Magnetotactic bacteria (MTB) are of interest in microbiology, biomineralization, advanced magnetic materials, and bio-geo-sciences because of their ability to form highly ordered intracellular magnetic minerals. Great strides for MTB studies have been made in the past four decades. In this paper we complied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It contains information of 16S rRNA gene sequences, corresponding ecological metadata, oligonucleotides, and magnetic properties of MTB. The comprehensive information contained in DMTB will provide a very useful data resource for researchers from different disciplines. The website of DMTB is at http://***/.

关键词： rRNA基因序列趋磁细菌 16S 网上资源寡核苷酸磁学性质生态磁性材料

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 {4. of Sciences, Beijing 10002., china 2. china University of Geosciences, Beijing 100083, chinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China 2. china University of Geosciences 100083 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.

Lower Cretaceous angio-sperm leaf from Wuhe in Anhui,china

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chinese Science Bulletin 2003年第6期48卷 611-614页

作者： LI Haomin Nanjing institute of geology and Palaeontology, chinese academy of Sciences, Nanjing 210008,{4. Nanjing institute of geology and Palaeontology Chinese Academy of Sciences China

A new early angiosperm leaf species is reported from the Xinzhuang Formation in Wuhe County, Anhui Province. It is probably of Barremian or slightly later in geological age. The fossil leaf is small, no more than 0.6 cm both in length and in width. The leaf veins are well preserved and clearly visible under a low power microscope. Leaf ar-chitectural analysis shows that such a leaf should belong to the first leaf rank of Hickey, i.e. the most primitive one. There are no early angiosperm leaves published completely similar to ours. A new species name of Dicotylophyllum minutissimum sp. nov. is established for the present leaf fos-sils.

关键词：安徽下白垩统早期被子植物叶片结构叶片化石