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Devonian ichnofossils and their environmental significance of northern belt of Western Qinling Mountains

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Science China Chemistry 1995年第1期38卷 85-96页

作者：李育慈晋慧娟 Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou 730000 China

It is beheved that the Shujiaba Formation belongs to a series of thick turbidites. 20 ichnogenera have been found in the formation, of which 14 genera were found in the Devonian System of China for the first time The ichnogenera are mostly of typical deep-water ones and belong to the Nereites ichnofacies A detailed study of morphology and behaviour of the trace fossils indicates that the Shujiaba Formation was deposited in a bathyal-abyssal environment.

关键词： Nereites ichnofacies terrigenous clastic turbidite series bathyal-abyssal sedimentary environment. Devonian Shujiaba Formation northern belt of Western Qinling Mountains.

Coral Ba/Ca and Mn/Ca Ratios as Proxies of Precipitation and Terrestrial Input at the Eastern Offshore Area of Hainan Island

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Journal of Ocean University of China 2017年第6期16卷 1072-1080页

作者： JIANG Qiaowen CAO Zhimin WANG Daoru LI Yuanchao WU Zhongjie NI Jianyu School of Marine Geosciences Ocean University of China Qingdao 266100 P. R. China Second Institute of Oceanography State Ocean Administration Hangzhou 310012 P. R. China Hainan Academy of Ocean and Fisheries Sciences Haikou 570125 P. R. China

Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set(1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island(19?12'28.4''N, 110?37'38.8''E) were analyzed using inductively coupled plasma-optic emission spectrometry(ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol^(-1) in 1903 to a maximum of 10.064 μmol mol^(-1) in 1944, with an average of 5.256 μmol mol^(-1). Mn/Ca ratios varied from 0.206 to 5.708 μmol mol^(-1) with an annual average of 1.234 μmol mol^(-1), with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future.

关键词： Porites lutea eastern offshore area of Hainan Island Ba/Ca and Mn/Ca ratios terrigenous input precipitation climate proxy records

Sedimentological Study of Caves in the Zemo Imereti Plateau, Georgia, Caucasus Region

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Open Journal of Geology 2017年第4期7卷 465-477页

作者： Lasha Asanidze Nino Chikhradze Zaza Lezhava Kukuri Tsikarishvili Jason Polk Giorgi Chartolani Vakhushti Bagrationi institute of Geography Ivane Javakhishvili Tbilisi State University Department of Geomorphology Tbilisi Georgia School of Natural Sciences and Engineering Ilia State University Tbilisi Georgia Center for Human Geo Environmental Studies Department of Geography and Geology Western Kentucky University Kentucky USA

The Zemo Imereti Plateau is located in the easternmost part of the limestone region of western Georgia and is Caucasus’ only karst plateau. It is centrally located in a relatively elevated part of the intermountain plain of the country of Georgia. Lithostratigraphical (petrographic, mineralogical, and XRD) research on terrigenous sediments found in caves in the region was conducted in the Upper Cretaceous limestones located at different hypsometric levels (400 - 700 m). This study focused on allochthonous deposits, which, due to sedimentological features, contains significant and complete information for paleogeographic reconstruction as opposed to the autochthonous sediments. Source provinces of the sediments’ origin were determined using petrographic analysis. Lithological study of the terrigenous sediments indicated their origin from the Racha range, as well as their transportation mechanisms, and sedimentation conditions during deposition. Approximate ages (the end of the Middle Pleistocene and the beginning of the Late Pleistocene) of ancient terrestrial sediments in Rganisklde Cave were achieved by taking into account the geological and geomorphological development of the region. Lithostratigraphical analysis of the cave deposits and modern archaeological data indicate that the formation of the caves in the Zemo Imereti plateau took place mainly during the end of the Middle Pleistocene and in the beginning of the Pleistocene;while on the southern slope of the Racha range and in the surrounding area of Ertso-Tsona (Caucasus southern slope), they formed in the Early Pleistocene.

关键词： terrigenous Sediments Geomorphologic Evolution Zemo Imereti Plateau Georgia

Distributions of pigments in reef sediments, contribution of phytoplankton to organic matter budget in coral reef

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Natural Science 2011年第5期3卷 344-350页

作者： Mohammed Rasheed Tariq Al-Najjar Said Damhoureyeh 不详

The temporal distributions of pigment on bio-genic calcareous and terrigenic reef sediments, chlorophyll a, chlorophyll b, chlorophyll c, fuco- xanthin, and porphine concentrations were mea- sured monthly in two sediment columns (0 - 15 cm) for one year. Pigment concentrations in-creased significantly during winter (Novem-ber-April) in both sediment types particularly in the upper layers of the sediments. Phytoplankton contributions to organic matter were found to be 8 ± 3 and 6 ± 2% in calcareous and terrigenous sediments respectively. The accumulation and the successive degradation of phytoplankton detritus to inorganic nutrients in calcareous sand may partly sustain the productivity of the coral reef communities which live in nutrient-poor environments.

关键词： Pigment Calcareous Sediments terrigenous Sediments

Current Situation and Application in Coal-Generated Hydrocarbons

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Global Geology 2001年第2期6卷 129-134页

作者： YANG Guang (College of Earth Science, Jilin University, Changchun, 130061, P.R.China) XU Hongdong (No.7 Oil Extraction Factory, Daqing Oil Field ltd., Heilongjiang Province, 163517, P.R.China) College of Earth Science Jilin University Changchun 130061 P.R. China No. 7 Oil Extraction Factory Daqing Oil Field ltd. Heilongiang Province 163517 P.R. China

The characteristics and research methods of terrigenous organic hydrocarbon-generated source rock in coal measures are studied in this thesis. After abundance of organic matters, pyrolysis parameter of rocks and hydrocarbon generated capacity of macerals are basically discussed in coal measures of the Cretaceous Muleng-Chengzihe formation in Suibin depression in Sanjang basin, the hydrocarbon generated grade in coal-genera^ted source rock is ascertained in this depression. At last, we think that it is a main attack prospect in coal-genera^ted hydrocarbons study in the future to research the macerals of coal measures organic source rock and to build a criterion to classify the coal-generated hydrocarbons in Northeast region.

关键词： Coal - generated Hydrocarbons, terrigenous Organic Matter, Olefiant System, Macerals, Suibin Depression.