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The hydrologic record of karst systems: linking soil moisture to the carbon isotope signatures of soils above the Blue Spring cave system

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Acta Geochimica 2017年第3期36卷 392-395页

作者： Yuchen Liu Jessica L.Oster Jennifer L.Druhan department of geology University of Illinois Urbana Champaign department of Earth and environmental Science Vanderbilt University

Speleothem carbonates are precipitated continuously from inorganic carbon dissolved in seepage water infiltrating from the land surface,that reflects a mixture of atmospheric CO_2,respired soil carbon,and epikarst sources,each with distinct δ^(13)C *** aid in deconvolving these signatures,soil samples were collected above the Blue Spring cave system in Sparta,Tennessee,USA and subjected to a series of incubation experiments,in order to constrain the correlation between CO_2respiration rates and soil *** relationship is used to parameterize a simple mixing model which predicts the relationship between δ^(13)C and soil moisture in fluids infiltrating into the underlying cave system.

关键词： Speleothem δ^13C CO2 respiration Soil moisture

Facies Analysis and Sequence Stratigraphy of the Qal'eh Dokhtar Formation(Middle-Upper Jurassic) in the West of Boshrouyeh, East Central Iran

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1797-1819页

作者： Mahnaz SABBAGH BAJESTANI Asadollah MAHBOUBI Reza MOUSSAVI-HARAMI Ihsan AL-AASM Mehdi NADJAFI department of geology Faculty of Sciences Ferdowsi University of Mashhad department of Earth and environmental Sciences University of Windsor

The study area is located in the east Tabas Block in Central Iran. Facies analysis of the Qal＇eh Dokhtar Formation（middle Callovian to late Oxfordian） was carried out on two stratigraphic sections and applied to depositional environment and sequence stratigraphy interpretation. This formation conformably overlies and underlies the marly-silty Baghamshah and the calcareous Esfandiar formations, respectively. Lateral and vertical facies changes documents low-to high energy environments, including tidal-flat, beach to intertidal, lagoon, barrier, and open-marine. According to these facies associations and absence of resedimentation deposits a depositional model of a mixed carbonate-siliciclastic ramp was proposed for the Qal＇eh Dokhtar Formation. Seven third-order depositional sequences were identified in each two measured stratigraphic sections. Transgressive systems tracts（TSTs） show deepening upward trends, i.e. shallow water beach to intertidal and lagoonal facies, while highstand systems tracts（HST） show shallowing upward trends in which deep water facies are overlain by shallow water facies. All sequence boundaries（except at the base of the stratigraphic column） are of the no erosional（SB2） types. We conclude eustatic rather than tectonic factors played a dominant role in controlling carbonate depositional environments in the study area.

关键词： Sequence stratigraphy Qal9eh Dokhtar Formation mixed sUiciclastic-carbonate ramp Jurassic Central Iran

A critical review of mineral-microbe interaction and co-evolution:mechanisms and applications

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National Science Review 2022年第10期9卷 209-229页

作者： Hailiang Dong Liuqin Huang Linduo Zhao Qiang Zeng Xiaolei Liu Yizhi Sheng Liang Shi Geng Wu Hongchen Jiang Fangru Li Li Zhang Dongyi Guo Gaoyuan Li Weiguo Hou Hongyu Chen Center for Geomicrobiology and Biogeochemistry Research State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences State Key Laboratory of Biogeology and environmental geology China University of Geosciences Illinois Sustainable Technology Center Illinois State Water Survey University of Illinois at Urbana-Champaign department of geology and environmental Earth Science Miami University

Mineral-microbe interactions play important roles in environmental change,biogeochemical cycling of elements and formation of ore *** provide both beneficial(physical and chemical protection,nutrients,and energy) and detrimental(toxic substances and oxidative pressure) effects to microbes,resulting in mineral-specific microbial *** impact dissolution,transformation and precipitation of minerals through their activity,resulting in either genetically controlled or metabolism-induced *** these interactions,minerals and microbes co-evolve through Earth ***-microbe interactions typically occur at microscopic scale but the effect is often manifested at global *** advances achieved through decades of research,major questions *** areas are identified for future research:integrating mineral and microbial ecology,establishing mineral biosignatures,linking laboratory mechanistic investigation to field observation,and manipulating mineral-microbe interactions for the benefit of humankind.

关键词： biomineralization co-evolution interactions microbe mineral nutrients

Palaeo-sea-ice changes on the North Icelandic shelf during the last millennium:Evidence from diatom records

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Science China Earth Sciences 2015年第6期58卷 962-970页

作者： SHA LongBin JIANG Hui LIU YanGuang ZHAO MeiXun LI DongLing CHEN ZhenLou ZHAO Yun Key Laboratory of Geographic Information Science East China Normal University Key Laboratory of Marine sedimentology and environmental geology First Institute of OceanographyState Oceanic Administration Key Laboratory of Marine Chemistry Theory and Technology of the Ministry of Education Ocean University of China department of City Science Ningbo University

A high resolution record of sea-ice concentration on the North Icelandic shelf during the last millennium has been reconstructed using a diatom-based sea-ice transfer function. The reconstructed sea-ice record for the top of sediment core MD99–2275 exhibits a slightly increasing trend over the last 1000 years. Prior to AD 1300 sea-ice abundance was generally below the mean value, suggesting the strong influence of warm waters from the Irminger Current during the Medieval Warm Period. A marked increase of sea-ice concentration indicates an abrupt change to colder conditions after AD 1300, corresponding to the onset of the Little Ice Age. The agreement between the reconstructed sea-ice concentration and IP25 data obtained from the same core, as well as with historical records of Icelandic sea ice, suggests that diatoms may provide a valuable tool for future quantitative reconstructions of past sea-ice variability. In addition, agreement between changes in the reconstructed sea-ice record and variations in the abundance of the major diatom components indicates that sea-ice conditions on the North Icelandic shelf are generally strongly influenced by changes in the strength of two different water masses, the cold Polar water periodically derived from the East Greenland Current and the warm Irminger Current derived from the North Atlantic Current. Our proxy evidence also indicates that variations in solar activity have a considerable impact on ocean dynamics, which in turn affects sea-ice abundance.

关键词： palaeo-sea-ice changes North Icelandic shelf Medieval Warm Period Little Ice Age

Development of Geothermal Resources in China: A Review

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Journal of Earth Science 2018年第2期29卷 452-467页

作者： Xiaobo Zhang Qinhong Hu School of environmental Studies State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences department of Earth and environmental Sciences University of Texas at Arlington

Geothermal resources in China are distributed throughout the country, with hydrother- real systems of high temperature in the Tibet Autonomous Region, Yunnan Province and Taiwan Island and hydrothermal systems of low-medium temperature mainly in various sedimentary basins. Devel- opment and exploration of geothermal energy in China are below expectations. The purpose of this study is to comparatively review the characteristics （geology, hydrogeology, hydrochemistry and geo- physical data） of typical hydrothermal fields/areas and suggest development and utilization approaches in the future. Hydrothermal systems formed by mountain Hfting contain a considerable amount of en- ergy for geothermal power generation, especially in the Tibet Autonomous Region, Yunnan Province and Taiwan Island. However, geothermal water in the Tatun geothermal field has high TDS （total dis- solved solids）, an issue that requires more research to resolve this problem for power generation. The large storage of geothermal resources has been investigated in Meso-Cenozoic sedimentary basins; it is basically used for heating, bathing or greenhouse plantation. Moreover, hydrothermal resources of low-medium temperature can also be used in binary power plants. Although the enhanced geothermal systems （EGS） in China are promising, the resources have not yet been commercially exploited, because the emerging technologies （hydraulic fracturing） and concerns over environmental impacts （induced miero-seismicity） lead to slow development. On the contrary, shallow geothermal energy has been di- rectly utilized mainly for heating and cooling buildings. Cities like Beijing, Tianjin and Shenyang have established a series of ground-source heat-pump systems, which has led to a massive reduction of CO2 emission of 19.87×10^6 t.

关键词： geothermal energy potential exploitation and utilization China.

Geometries and mechanism of folds in sediments on the southern Huanghai Sea shelf

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Acta Oceanologica Sinica 2006年第4期25卷 23-31页

作者： LI Xishuang LIU Baohua ZHAO Yuexia LI Sanzhong Earth Science College Ocean University of China Qingdao 266003 China Key Laboratory of Marine sedimentology ＆ environmental geology of State Oceanic Administration Qingdao 266061 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

Most descriptions and studies about folds have been associated with consolidated strata; fold deformation in loosely-consolidated sediments, however, has been rarely discussed. Since the Pleistocene, tectonic activities have been intensive over the South Huanghai Sea （SHS） shelf, resulting in fold deformation features that are preserved in thick sediment layers. Four types of folds with different geometries have been identified on the basis of an analysis of single - channel seismic profiles from the SHS shelf region：（1） fault-propagation fold; （2） fault-drag fold; （3） transversal bending fold; and （4） multi-action-folding fold. Studies on the geometry and mechanism of the folds indicate that base faults and fault blocks control the folding patterns in loosely-consoli- dated sediments on the SHS shelf and a large quantity of pore water in sediments plays an important role in cansing the deformation of sediment layers. The continuity of deformations of fault-propagation fold and fault-drag fold indicates that there is a genetic relationship between these fold types. The potential of earthquakes induced by fault-propagation folding in the deformation zone should be taken into account in the assessment of the marine engineering geology conditions of the SHS shelf.

关键词： fold loosely-consolidated sediment base fault marine engineering south Huanghai Sea shelf

Crystallization Conditions and Petrogenesis of the Paleoproterozoic Basement Rocks in Bangladesh:An Evaluation of Biotite and Coexisting Amphibole Mineral Chemistry

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Journal of Earth Science 2014年第1期25卷 87-97页

作者： Ismail Hossain Toshiaki Tsunogae department of geology and Mining University of Rajshahi Faculty of Life and environmental Sciences (Earth Evolution Sciences) University of Tsukuba department of geology University of JohannesburgAuckland Park 2006

The Paleoproterozoic （-1.73 Ga） basement rocks from Maddhapara, Bangladesh show a large range of chemical variations including diorite, quartz diorite, monzodiorite, quartz monzonite and granite. These are composed of varying proportions of quartz＋plagioclase＋K-feldspar＋biotite＋ hornblende±epidote＋titanite＋magnetite＋apatite and zircon. Amphibole and biotite, dominant ferro- magnesian minerals, have been analyzed with an electron microprobe. The biotite, Mg-dominant trioc- tahedral micas, is classified as phlogopitic nature. Relatively high Mg （1.33-1.53 pfu）, Mg^# （0.52-0.59） and low AIw （0.13-0.25 pfu） contents in the biotite reflect slightly fractionated magma, which might be a relative indicator for the origin of the parental magma. Biotite is also a very good sensor of oxidation state of the parental magma. Oxygen fugacity of the studied biotites estimate within the QFM and HM buffers and equilibrate at about -12.35 and -12.46, which exhibit the source materials were relatively higher oxidation state during crystallization and related to arc magmatism. Whereas, calcic amphi- boles, a parental member of arc-related igneous suite, display consistent oxygen fugacity values （-11.7 to -12.3）, low Al^# （0.16-0.21） with H2Omelt （5.6 wt.%-9.5 wt.%） suggest their reliability with the typical values of calc-alkaline magma crystallization. The oxygen fugacity of magma is related to its source material, which in turn depends on tectonic setting. Discrimination diagrams and chemical indices of both biotite and amphibole of dioritic rocks reveal calc-alkaline orogenic complexes; mostly I-type suite formed within subduction-related environments. Moreover, igneous micas are used as metal- logenic indicator. The biotites with coexisting amphibole compositions show an apparent calc-alkaline trend of differentiation. The study suggests that the trend of oxidized magmas is commonly associated with compressive tectonic and convergent plate boundaries.

关键词： oxygen fugacity biotite Paleoproterozoic basement rock Columbia supercontinent Bangladesh.

Contribution of phytoliths to total biogenic silica volumes in the tropical rivers of Malaysia and associated implications for the marine biogeochemical cycle

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Chinese Journal of Oceanology and Limnology 2016年第5期34卷 1076-1084页

作者：臧家业刘森刘焱光马永星冉祥滨 Marine Ecology Research Center First Institute of OceanographyState Oceanic Administration Tianjin Marine environmental Monitoring Central Station State Oceanic Administration Key Laboratory of Marine sedimentology and environmental geology First Institute of OceanographyState Oceanic Administration College of Chemistry and Engineering Qingdao University

The contribution of phytoliths to total biogenic silica(BSi) volumes in rivers worldwide,and the associated implications for the biogeochemical cycle,require in-depth *** on samples from rivers in Peninsular Malaysia,this project investigated the source and characteristics of B Si found in Asian tropical rivers,as well as the process of reverse weathering taking place in these fluvial *** indicated that BSi samples collected in sediments consisted of phytolith,diatom and sponge ***,predominantly of the elongate form,comprised 92.8%-98.3% of BSi in the Pahang *** BSi in this river consisted mainly of pennatae diatoms,but represented a relatively small proportion of the total BSi ***,diatom BSi(predominantly of the Centricae form) was more prevalent in the Pontian and Endau Rivers with shares of 68.8% and 79.3% of the total BSi volumes,respectively,than Pahang *** contents of the BSi particulates ranged from 1.85% to 10.8% with an average of 4.79%.These values are higher than those recorded in other studies to date,and indicate that BSi plays a major role in controlling permanent carbon *** study suggests that phytoliths from terrestrial plants are the primary constituents of BSi in the rivers of Peninsular Malaysia,and therefore represent a significant proportion of the coastal silica budget.

关键词： biogenic silica phytolith diatom Malaysia biogeochemical cycle

Partitioning of grain-size components of estuarine sediments and implications for sediment transport in southwestern Laizhou Bay, China

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Chinese Journal of Oceanology and Limnology 2013年第4期31卷 895-906页

作者：陈广泉易亮陈沈良黄海军刘艳霞徐勇航曹建荣 State Key Laboratory of Estuarine and Coastal Research East China Normal University Key Laboratory of Marine sedimentology and environmental geology First Institute of OceanographyState Oceanic Administration State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Marine geology and Environment Institute of OceanologyChinese Academy of Sciences Open Laboratory of Ocean & Coast environmental geology Third Institute of OceanographyState Oceanic Administration College of Environment and Planning Liaocheng University

Sediment transport in estuarine systems has been of increasing interest for scientists during the past few decades. However, the mechanisms for sediment redistribution remain unclear. We characterized in detail sediment transport in the Xiaoqing River estuary using the mathematical Weibull function to partition grain-size components of surface sediments in the southwestern Laizhou Bay, Northeast China. Four partitioned components: finer than 4,4.6-12.5, 23.4-63.3, and 67.1-132.6 μm were interpreted in terms of hydrodynamic conditions. During sediment transport, silt grains were suspended and moved seaward from three depositional centers, whereas fine-grained sands moved generally landward. Overall, sediments are transported clockwise in a generally NNE direction near shore and then turn eastward offshore. The mathematical partitioning method showed a great potential for future estuarine environmental studies.

关键词： sediment transport estuarine environment sediment grain size mathematical partitioning Laizhou Bay (China)