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Geochemical Characterization and Origin of High-Sulfur,Heavy Oils in Jiyang Sub-Basin,East China

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Acta Geologica Sinica(English Edition) 2011年第4期85卷 923-931页

作者： WANG Guangli WANG Tieguan ZHANG Linye State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China institutes of geological Science SINOPEC Shengli Oilfield CompanyDongying 257015China

High-sulfur,heavy petroleum is widely occurring in the Tertiary lacustrine Jiyang sub-basin, Bohai Bay *** are differentiated into two families based on the bulk properties and biomarker *** 1 is characterized by high resins（40%-71%）and sulfur（2%-4%）,and low wax （l%-6%）,with n-alkanes removed by biodegradation,whereas family 2 is characterized by extremely abundant sulfur（3%-10%）,and high asphaltenes（7%-31%）and wax（2%-19%）,with no evidence of microbial *** oils of family 1 are distributed in the reservoir,lower than 1500 m throughout the *** assemblages,such as low pristane/phytane ratios（1 Pr/Ph）and a high abundance of carotane,gammacerane,and dinosterane,suggest that they are derived from the calcareous mudstones and shales among the stratified,saline Es_4~u unit,in addition to the in situ biodegradation-concentrated sulfur ***,the oils of family 2 are identified only in the western Zhanhua and eastern Chezhen depressions,with a depth deeper than 1700 *** properties,together with biomarker ratios,including even-numbered n-alkanes,1 Pr/Ph,trace diasteranes,higher C35 homohopanes,and abundant dibenzothiophene series,with1 dibenzothiophene/phenanthrene,indicate an origin from carbonate source *** X-ray diffraction analysis showed that the carbonate source rock is limited in the Es_4~u unit of the Bonan sag,which is different from most other source rocks in the same *** is suggested that the high-sulfur,heavy oils are generated at the early stage of the oil *** sulfate reduction might be responsible for the occurrence of sulfur species in the high-sulfur,heavy oils,while heavy biodegradation will enhance sulfur concentrations.

关键词： high-sulfur heavy oil bacterial sulfate reduction biodegradation lacustrine carbonate

Preparation and Microwave Absorbing Properties of Double-layer Fine Iron Tailings Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1126-1135页

作者： LI Huawei WANG Rong WANG Yulin LIU Feiyu WANG Qian WEI Muwang School of Civil Engineering and Architecture Wuyi UniversityWuyishan 354300China Engineering Research Center of Prevention and Control of geological Disasters in Northern Fujian Fujian Province Higher Education InstitutesWuyishan 354300China

To develop the microwave absorbing(MA)properties of cementitious material mixed with mine solid waste,the iron tailings cementitious microwave absorbing materials were *** iron tailings was treated into different particle sizes by planetary ball mill,and the physicochemical properties of iron tailings were tested by laser particle size analyzer and scanning electron microscope(SEM).The electromagnetic parameters of iron tailings cementitious materials were characterized by a vector network analyzer and simulated MA properties,and the MA properties of iron tailings-cement composite system with steel fiber as absorber was *** on the design of the single-layer structure,optimum mix ratio and thickness configuration method of double-layer structure were further studied,meanwhile,the mechanical properties and engineering application were analyzed and *** results show that the particle size of iron tailings can afiect its electromagnetic behavior in cementitious materials,and the smaller particles lead the increase of demagnetisation efiect induced by domain wall motion and achieve better microwave absorbing properties in cementitious *** the thickness of matching layer and absorbing layer is 5 mm,the optimized microwave absorbing properties of C1/C3 double-layer cementitious material can obtain optimal RL value of-27.61 dB and efiective absorbing bandwidth of 0.97 GHz,which attributes to the synergistic efiect of impedance matching and attenuation *** double-layer microwave absorbing materials obtain excellent absorbing properties and show great design flexibility and diversity,which can be used as a suitable candidate for the preparation of favorable microwave absorbing cementitious materials.

关键词： microwave absorbing properties iron tailings electromagnetic parameters single-layer structure double-layer structure impedance matching

Using our mini-brains: cerebral organoids as an improved cellular model for human prion disease

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Neural Regeneration Research 2020年第6期15卷 1019-1020页

作者： Bradley R.Groveman Ryan walters Cathryn L.Haigh Laboratory of Persistent Viral Diseases National Institute of Allergy and Infectious Diseases Division of Intramural ResearchRocky Mountain Laboratories National Institutes of Health

Neurodegenerative diseases are an ever-increasing burden in an aging *** no cure is available for any of these diseases and treatment is based on managing *** many candidate therapeutics demonstrating promise in animal models,none has yet shown efficacy in human *** is self-evident that humans are different from the animals used to model our diseases,especially models that have been highly manipulated to generate a disease in an animal that does not naturally have such a *** differences are likely the reason for the failures of drug candidates in human trials but,until recently,human models of neurodegenerative diseases were *** development of the human cerebral organoid model,by differentiating three-dimensional human neuronal tissue from pluripotent stem cells,represents a significant advance in studying human brain *** organoids have been used to model Alzheimer’s disease,Parkinson’s disease,Down’s syndrome dementia and we have now shown they can be infected with human prions creating a new model of human prion diseases.

关键词： cerebral likely spite

Tectonic Evolution of the Meso-Tethys in the Western Segment of Bangonghu-Nujiang Suture Zone: Insights from Geochemistry and Geochronology of the Lagkor Tso Ophiolite

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 369-388页

作者： YUAN Yajuan YIN Zhengxin LIU Weiliang HUANG Qiangtai LI Jianfeng LIU Hongfei WAN Zhifeng CAI Zhourong XIA Bin School of Marine Sciences Sun Yat-sen University Key Laboratory of Offshore Oil Exploration and Development of Guangdong Higher Education institutes Guangzhou Institute of Geochemistry Chinese Academy of Sciences Xizang geological Survey

The subduction of the Bangonghu-Nujiang Meso-Tethys and the collision between the Lhasa and Qiangtang blocks were important events in the growth of the Tibetan crust. However, the timing of collision initiation and closure timing, as well as nature and structure of the Bangonghu ocean basin, are still poorly constrained. The Lagkor Tso ophiolite, located in the south of Gerze County, Tibet, is one of the most completed ophiolites preserved in the southern side of the Bangonghu- Nujiang suture zone. This study discussed the tectonic evolution of the Bangonghu-Nujiang suture zone as revealed by the Lagkor Tso ophiolite investigated by field investigations, petrology, geochemistry, geochronology and tectonic analysis methods. We present new LA-ICP-MS zircon U-Pb and 39Ar/4~Ar ages for the Lagkor Tso ophiolite, in addition to geochemical and platinum-group element （PGE） data presented for the Lagkor Tso ophiolite in Tibet. It is suggested that the ancient Lagkor Tso oceanic basin split in Middle Jurassic （161.2 ± 2.7 Ma - 165.4 ± 3.5 Ma）, and experienced a second tectonic emplacement during the Early Cretaceous （137.90 ± 6.39 Ma）. The Lagkor Tso ophiolite likely developed in an independent suture zone. The Bangonghu-Nujiang ocean subducted southwards, and the dehydration of the subducting oceanic crust materials caused partial melting of the continental mantle wedge, which formed the second-order expanding center of the obduction dish. This led to inter-arc expansion, followed by the formation of inter-arc and back-arc basins with island arc features, which are represented by ophiolites around the Shiquanhe-Lagkor Tso -Yongzhu region. The tectonic environment presently can be considered to be similar to that of the current Western Pacific, in which a large number of island arc-ocean basin systems are developed.

关键词： ophiolite geochemistry geochronology inter-arc basin Lagkor Tso Bangonghu-Nujiangsuture zone

The significance of cherts as markers of Ocean Plate Stratigraphy and paleoenvironmental conditions:New insights from the Neoproterozoic-Cambrian Blovice accretionary wedge,Bohemian Massif

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Geoscience Frontiers 2023年第1期14卷 162-180页

作者： LukášAckerman Jirízák Václav Kachlík Jan Pašava KarelZák Andreas Pack František Veselovsky Ladislav Strnad Institute of Geology of the Czech Academy of Sciences Rozvojová269CZ-16500 Prague 6Czech Republic Czech geological Survey Klárov3CZ-11821 Prague 1Czech Republic Institute of Geology and Paleontology Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic Geowissenschaftliches Zentrum Universität GöttingenGoldschmidtstraβe 1D-37077 GöttingenGermany laboratories of the geological institutes Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic

The Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of *** relationships of cherts to their host,their microstructure and elemental as well as isotopic compositions revealed diverse processes of chert petrogenesis reflecting depositional environment and position on the oceanic *** deep-water cherts formed through a hydrothermal precipitation of silica-rich gels on outer trench swell of the subducted slab with none or only minor addition of terrigenous *** the contrary,the shallow-water cherts formed in lagoons on seamount slopes,and at least some of them represent a product of hydrothermal replacement of former carbonate and/or evaporite *** both chert types,the hydrothermal fluids were of low temperature and continuous pervasive hydrothermal alteration of oceanic crust,together with an elevated Si content in Neoproterozoic seawater,served as the major source of *** the other hand,minor carbon enrichment in chert is mostly linked to variable incorporation of organic matter that was deposited on the *** earth element(REE)systematics of the cherts indicate predominantly oxygenated environment for the shallow-water cherts whereas the deep-water cherts were deposited in diverse redox conditions,depending on their distance from hydrothermal *** these data,we demonstrate that the cherts once formed a part of Ocean Plate Stratigraphy(OPS)now dismembered and mixed with terrigenous siliciclastic material to form OPS mé*** our data with those from the existing literature,we show that cherts can serve as significant markers of OPS since the Archean,recording a complex interplay between seafloor-related volcanic(production of MORB-and OIB-like magmas)and sedimentary processes,hydrothermal activity at mid-ocean ridges and seamount chains as well as at outer slopes o

关键词： Chert Accretionary wedge Ediacaran Triple oxygen isotopes Strontium isotopes Ocean Plate Stratigraphy

The Late Carboniferous–Early Permian Ocean-Continent Transition in the West Junggar,Central Asian Orogenic Belt: Constraints from Columnar Jointed Rhyolite

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 265-282页

作者： XU Shenglin CHEN Xuanhua LI Tingdong SHI Jianjie DING Weicui LI Bing HUANG Penghui ZHANG Yiping ZHANG Yaoyao MA Feizhou School of Earth Sciences and Resources China University of Geosciences Chinese Academy of geological Sciences Beijing Research Institute of geological Engineering Design

The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean-continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first *** on zircon U-Pb dating, we determined that the ages of the newly-discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO_2(75.78–79.20 wt%) and a moderate content of Al_2O_3(12.21–13.19 wt%). The total alkali content(K_2O +Na_2O) is 6.14–8.05 wt%, among which K_2O is 2.09–4.72 wt% and the rate of K_2O/Na_2O is 0.38–3.05. Over-based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO_2(0.09–0.24 wt%), CaO(0.15–0.99 wt%) and MgO(0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi-aluminum-weak peraluminous high potassium calc-alkaline and some calc-alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE(Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE(Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2-type granite, similar to the Miaoergou batholith,which indicates they both were affected by post-orogenic extension. Combining petrological, zircon U-Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean-continent transition of the West Junggar is the Late Carboniferous–Early Permian.

关键词： rhyolite columnar joint zircon U-Pb dating geochemistry ocean-continent transition West Junggar

Density Calculation for NaCl-H_2O Solutions in the Liquid-Solid TwoPhase Field in NaCI-H_2O Three-Phase Inclusions

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Acta Geologica Sinica(English Edition) 2015年第3期89卷 911-917页

作者： CHEN Wenming WANG Yong CHEN Weishi Institute of Mineral Resources Chinese Academy of Geological Sciences

Three-phase NaCl-H_2O fluid inclusions featuring halite dissolution temperature（Tm）higher than vapor bubble disappearance temperature（T_h） are commonly observed in porphyry copper/molybdenum deposits,skarn-type deposits and other magmatic- hydrothermal ore *** on ｜ΔV_1｜（the absolute value of volume variation of NaCl-H_2O solution in a heating or cooling process of inclusions）= ｜ΔV_s｜（the absolute value of volume variation of the halite crystal in a heating or cooling process of inclusions） and on the principle of conservation of the mass of NaCl and H_2O,we systematically calculated the densities of NaCl-H_2O solutions in the solid-liquid two-phase field for temperatures（T_h） from 0.1℃ to 800℃ and salinities from 26.3 wt%to 99.2wt%.Consequently for the first time we obtained the upper limit of the density of NaCI-H_2O solutions in the solid-liquid twophase field for T_b〈T_m inclusions with variant *** results indicate that for inclusions of the T_h〈T_m type with the same T_h,the higher the T_m or salinity is,the higher the density of the NaClsaturated solution will *** a group of fluid inclusions were homogeneously trapped,they must have the same T_h value and the same T_m or salinity *** may be used to distinguish homogeneous,inhomogeneous,and multiple entrapments of fluid inclusions.

关键词： Density calculation NaCl-H2O three-phase inclusions Th〈Tm homogeneous trapping,solid-liquid two-phase field

Reclamation of oil-induced soil hydrophobicity in the hyper-arid Evrona Nature Reserve,southern Israel

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Pedosphere 2021年第6期31卷 892-902页

作者： Zheng LI Zeev RONEN Faina GELMAN Onn CROUVI Gilboa ARYE Ravid ROSENZWEIG Zuckerberg Institute for Water Research Jacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer Campus 8499000(Israel) geological Survey of Israel 32 Yeshayahu Leibowitz St.Jerusalem 9692100(Israel) French Associates Institute for Agriculture and Biotechnology of Drylands Blaustein institutes for Desert Research Ben-Gurion University of the NegevSede Boqer Campus 8499000(Israel)

Two oil spills occurred in the Evrona Nature Reserve(southern Israel),in 1975 and *** oil contamination induced highly persistent soil *** objective of this study was to investigate the decrease in oil-induced soil hydrophobicity under different environmental conditions and to assess the relationship between the hydrophobicity and hydrocarbon content.A laboratory incubation experiment was conducted over 1.5 years to monitor the soil hydrophobicity and total hydrocarbon concentration under different environmental *** hypothesized that the addition of water(20% or 50% saturation),nutrients,and biosurfactants can accelerate the reduction in hydrophobicity and decomposition of *** drop penetration time and molarity of ethanol droplet tests were used to assess soil *** parallel,alkane composition and total petroleum hydrocarbons were evaluated to indicate oil *** addition of water,nutrients,and biosurfactants resulted in a concomitant reduction in hydrophobicity and hydrocarbon concentration of varying degrees,exhibiting enhanced degradation and hydrophobicity reduction observed in treatments to which nutrients and biosurfactants were *** the end of the incubation,however,soil hydrophobicity in all treatments remained severe,even though total petroleum hydrocarbon removal was fairly high and reached 40%–80%in the treatments to which water with or without nutrients and/or surfactants was added.

关键词： biodegradation biosurfactant hydrocarbons oil spill soil water repellency water drop penetration time

Diffusion of helium in FCT zircon

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Science China Earth Sciences 2019年第4期62卷 719-732页

作者： Shun YU Wen CHEN Jingbo SUN Ze SHEN Laboratory of Isotope Thermochronology Institute of Geology Chinese Academy of Geological Sciences Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological Sciences

To gain a better quantitative understanding of zircon(U-Th)/He ages and evaluate the applicability of zircon(U-Th)/He dating, the diffusion characteristics, He diffusion kinetics, helium partial retention zone(HePRZ), closure temperature, and(U-Th)/He ages were investigated using high-precision laboratory step heating experiments based on the thermally activated diffusion process. The ln(D/a^2) in Fish Canyon Tuff(FCT) zircons determined from laboratory step heating experiments was negatively correlated with reciprocal temperature, as expected for thermally activated volume diffusion. The zircon activation energies ranged from 144 to 184 kJ mol^(-1) with a mean of 169±12 kJ mol^(-1). The closure temperatures ranged from 144 to 216°C(a cooling rate of 10°C Ma^(-1) and an effective grain radius of 38–60 μm) with an average of 176±18°C. The calculated closure temperature increased with increasing cooling rate, yielding an average zircon He closure temperature of ～136°C at a slow cooling rate of 0.1°C Ma^(-1), whereas the closure value was ～199°C at a cooling rate of 100°C Ma^(-1). The closure temperature increased with the equivalent spherical radius assuming a constant cooling rate. The He ages from FCT zircons were negligibly affected by grain size because of the rapid cooling. He preserved in the zircon was sensitive to temperature and holding time, and the temperature range for zircon HePRZ gradually decreased with increasing holding time. The(U-Th)/He ages from 26 FCT zircons yielded an algorithmic mean of 28.3±0.3 Ma(S.E.) and a geometric mean of 28.4±0.3 Ma(S.E.), consistent with the ages of 28.4±1.9 Ma reported by other laboratories. The FCT zircons were characterized by rapid cooling, young(U-Th)/He ages with good reproducibility, and low alpha doses. Weak correlations between the He ages and effective uranium(eU) concentrations from the FCT zircons indicated radiation damage did not significantly affect He diffusivity.

关键词： Zircon Helium diffusion (U-Th)/He Closure temperature Thermochronometry