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Frontiers of Earth Science 2013年第2期7卷 238-256页

作者： WeiZHANG National Geological Library of China (geoscience documentation center) China Geological Survey Beijing 100083 China

It is well known that during CO2 geological storage, density-driven convective activity can significantly accelerate the dissolution of injected CO2 into water. This action could limit the escape of supercritical CO2 from the storage formation through vertical pathways such as fractures, faults and abandoned wells, consequently increasing permanence and security of storage. First, we investigated the effect of numerical perturbation caused by time and grid resolution and the convergence criteria on the dissolution-diffusion-convection （DDC） process. Then, using the model with appropriate spatial and temporal resolution, some uncertainty parameters investigated in our previous paper such as initial gas saturation and model boundaries, and other factors such as relative liquid permeability and porosity modification were used to examine their effects on the DDC process. Finally, we compared the effect of 2D and 3D models on the simulation of the DDC process. The above modeling results should contribute to clear understanding and accurate simulation of the DDC process, especially the onset of convective activity, and the CO2 dissolution rate during the convection-dominated stage.

关键词： climate change carbon dioxide geologic sequestration density-driven convection reactive transport modeling grid resolution

Status of CCUS research and governance by worldwide geological surveys and organizations

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China Geology 2023年第3期6卷 536-540页

作者： Huan Wang Jia-jia Xu Yang Yu geoscience documentation center China Geological SurveyBeijing100083

Over the past decade,energy-related carbon dioxide(CO_(2))emissions have steadily increased worldwide,reaching 33.4 billion tons in *** climate scenarios suggest that carbon capture,utilization,and storage(CCUS)is critical for the reduction of direct CO_(2)emissions from industrial processes and the use of fossil fuels in power generation,industrial activities,and fuel ***.

关键词： CCUS dioxide emissions

Earth's Solid Inner Core: Seismic Implications of Freezing and Melting

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Journal of Earth Science 2013年第5期24卷 683-698页

作者： Vernon F Cormier Januka Attanayake Department of Physics University of Connecticut center for Integrative geoscience University of Connecticut center for Integrative geoscience University of Connecticut

Seismic P velocity structure is determined for the upper 500 km of the inner core and lowermost 200 km of the outer core from differential travel times and amplitude ratios. Results confirm the existence of a globally uniform F region of reduced P velocity gradient in the lowermost outer core, consistent with iron enrichment near the boundary of a solidifying inner core. P velocity of the inner core between the longitudes 45~E and 180~E （quasi-Eastern Hemisphere） is greater than or equal to that of an AK135-F reference model whereas that between 180~W and 45~E （quasi-Western Hemisphere） is less than that of the reference model Observation of this heterogeneity to a depth of 550 km below the inner core and the existence of transitions rather than sharp boundaries between quasi-hemispheres favor either no or very slow inner core super rotation or oscillations with respect to the mantle. Degree- one seismic heterogeneity may be best explained by active inner core freezing beneath the equatorial Indian Ocean dominating structure in the quasi-Eastern Hemisphere and inner core melting beneath equatorial Pacific dominating structure in the quasi-Western Hemisphere. Variations in waveforms also suRgest the existence of smaller-scale （1 to 100 km） heterogeneity.

关键词： Earth's inner core seismic structure geodynamo.

Site-Specific Zonation of Seismic Site Effects by Optimization of the Expert GIS-Based Geotechnical Information System for Western Coastal Urban Areas in South Korea

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International Journal of Disaster Risk Science 2019年第1期10卷 117-133页

作者： Han-Saem Kim Chang-Guk Sun Hyung-Ik Cho Earthquake Research center Korea Institute of Geoscience and Mineral Resources Geological Research Division Korea Institute of Geoscience and Mineral Resources

Earthquake-induced disasters are often more severe over soft soils than over firm soils or rocks owing to the seismic site effects related to the amplification of ground motion. On a regional scale, such differences can be estimated by spatially predicting the subsurface soil thickness over the entire target area. Generally, soil deposits are deeper in coastal or riverside areas than in inland regions. In this study, the seismic site effects in the coastal metropolitan areas of Incheon and Bucheon, South Korea, were assessed to provide information on seismic hazards. Spatial prediction of geotechnical layers was performed for the entire study area within an advanced GIS framework. Approximately 7500 existing borehole records in the Incheon and Bucheon areas were gathered and archived into a GIS database. Surface geotechnical data were acquired from a walk-over survey. Based on the optimized geo-data, spatial zoning maps of site-specific seismic response parameters, based on multiscale geospatial modeling, were created and presented for use in a regional seismic mitigation strategy. Seismic zonation was also performed to determine site coefficients for seismic design over the entire target area and to compare them with each other. We verified that the geotechnical data based spatial zonation would be useful for seismic hazard mitigation.

关键词： Coastal urban areas Geodata Geostatistical spatial zonation Seismic site effects Site classification South Korea

The Study on Metallogenetic Rule and Metallogenic Prognosis in Eastern Tianshan,Xingjiang

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The Study on Metallogenetic Rule and Metallogenic Prognosis ...

Origin,discovery,exploration and development status and prospect of global natural hydrogen under the background of“carbon neutrality”

作者： Yi LUO geoscience documentation center China Geological Survey

This thesis takes Tuwu-Yandong copper porphyry metallogenetic belt in East Tianshan,Xinjiang as research *** expatiating metallogenetic background and studying deposit geological character,the author simply analyze ore controlled condition,generalize metallogenetic rule and discuss deposit’s genetic *** thesis also instruct metallogenetic prognosis study in copper porphyry *** volcanic rock of Yandong copper deposit is alkali calcic rock,and the rock in which metallization occurred located in orogenic zone（arc and active ocean margin）.Throught the study of geochemistry of trace elements,the invasion environment of granite magma was volcanic arc and intraplate *** character of the copper mineralization markfieldite shows that copper porphyry dependent magma stem from exo mantle basalt,and copper porphyry is *** homogenization temperature of fluid inclusion shows that the mineralization islimited to low-to-moderate *** and Yandong copper deposit are（volcano） faults controlled,hypabyssal-super hypabyssal intimate low-to-moderate temperature volcanogere hydrothermal copper porphyry *** on the survey of geology,geophysics,geochemistry and remote sense,we identified two big abnormities included Tuxi target and Yanxi *** elementarily evaluating,we suspect that they could be looked upon as ore prospecting *** author also forecast deep prospection potential of Tuwu and Yandong copper *** optimize Fuxingbei district as further ore prospecting area of copper porphyry ***-Yandong copper porphyry metallogenetic belt has great copper porphyry potential.

关键词： Eastern Tianshan Tuwu-Yandong copper porphyry belt metallogenetic rule metallogenic prognosis

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China Geology 2022年第4期5卷 722-733页

作者： Qian-ning Tian Shu-qing Yao Ming-juan Shao Wei Zhang Hai-hua Wang geoscience documentation center China Geological SurveyMinistry of Natural ResourcesBeijing 100083China National Geological Library of Chin1 2eijing 100083China

Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by *** is considered to be the most potential clean energy in this century under the background of carbon *** present,the industrial methods for producing hydrogen are mainly by steam-hydrocarbon(such as coal and natural gas)reforming and by electrolysis of water,while the exploration and development of natural hydrogen had just *** to this literature review:(1)Natural hydrogen can be divided into three categories,including free hydrogen,hydrogen in inclusions and dissolved hydrogen;(2)natural hydrogen could be mainly from abiotic origins such as by deep-seated hydrogen generation,water-rock reaction or water radiolysis;(3)natural hydrogen is widely distributed and presents great potential,and the potential natural hydrogen sources excluding deep source of hydrogen is about(254±91)×10^(9) m^(3)/a according to a latest estimate;(4)at present,natural hydrogen has been mined in Mali,and the exploration and development of natural hydrogen has also been carried out in Australia,Brazil,the United States and some European countries,to find many favorable areas and test some technical methods for natural hydrogen *** hydrogen is expected to be an important part of hydrogen energy production in the future energy *** on a thorough literature review,this study introduced the origin,classification,and global discovery of natural hydrogen,as well as summarized the current global status and discussed the possibility of natural hydrogen exploration and development,aiming to provide reference for the future natural hydrogen exploration and development.

关键词： Carbon neutrality Energy transition New energy Hydrogen energy Natural hydrogen Occurrence Genesis Resources Exploration and development Potential

Thematic harvesting of agricultural resources from generic repositories

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Information Processing in Agriculture 2015年第2期2卷 93-100页

作者： Devika P.Madalli documentation Research and Training center(DRTC)Indian Statistical Institute(ISI) 560059India

Metadata aggregators and service providers harvest entire collections or they restrict harvesting by date or *** most often user approach to collections is not by dates or set names but by domain based *** by domains is an issue when service providers attempt to collect data from multiple *** main problem is that harvesters,at present,do not have the facility to distinguish themes such as *** the present work,an attempt has been through Tharvest,a thematic harvester model using the proposed methodology harvesting agricultural resources from generic *** encompasses a process where technical terms of the domain of agriculture are taken from AGROVOC,a multilingual,structured controlled vocabulary designed to cover concepts and terminologies in the agriculture *** is deployed to provide the basis for selective *** system components and workflows are presented and *** aggregators provide end-users a single platform discovery facility to resources collected from various data *** is observed that aggregators such as INDUS[***/***/indus]dealing with agriculture and related domains facilitate aggregating metadata from not only repositories but also other sources such as journals and enable a centralized access to full text and *** harvesting can be fairly simple and straight forward,it is not without its *** paper intends to highlight some of the issues in harvesting metadata in agricultural *** particular focus is to identify agriculture related metadata from generic sets.

关键词： Thematic harvesting Agricultural data Issues in harvesting

Heavy mineral stratigraphy of sediments from the southern outer shelf of the East China Sea since the last glaciation using fuzzy C-means cluster method

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Chinese Journal of Oceanology and Limnology 2010年第1期28卷 183-189页

作者：林晓彤李巍然杜树杰林振宏 Computer center of Ocean University of China College of Marine geoscience Ocean University of China

Correspondence analysis and fuzzy C-means cluster methods were used to divide the stratigraphy of heavy mineral assemblages, and the sediment sources and depositional dynamics of the environment reconstructed. The assemblages were taken from marine sediments from the late Pleistocene to the Holocene in Core Q43 situated on the outer shelf of the East China Sea. Based on the variable boundaries of the mineral assemblage at 63 and 228 cmbsf （cm below sea floor）, the core might have previously been divided into three sediment strata marked with units Ⅰ, Ⅱ and Ⅲ, which would be consistent with the divided sediment stratum of the core using minor element geochemistry. The downcore distribution of heavy minerals divided the sedimentary sequence into three major units, which were further subdivided into four subunits. The interval between 0 and 63 cmbsf of the core （unit Ⅰ）, which spans the Holocene and the uppermost late Pleistocene, is characterized by a hornblende-epidote-pyroxene assemblage, and contains relatively a smaller amount of schistic mineral and authigenic pyrite. In comparison, the interval between 63 and 228 cmbsf （unit Ⅱ）, is representative of the Last Glacial Maximum （LGM）, and features a hornblende-epidote-magnetite-ilmenite assemblage containing the highest concentrations of heavy minerals and opaque minerals. However, the interval between 228 and 309 cmbsf （unit Ⅲ）, which spans the subinterglacial period, is characterized by a hornblende-authigenic-pyrite-mica assemblage. Relative ratios of some heavy minerals can be used as tracers of clastic sediment sources. The lower part of the sediment core shows the highest magnetite/ilmenite ratio and relatively high hornblende/augite and hornblende/epidote ratios. The middle core shows the highest hornblende/augite and hornblende/epidote ratios, and the lowest magnetite/ilmenite ratio. The upper part exhibits a slightly higher magnetite/ilmenite ratio, and also the lowest hornblende/augite and hornblende/epido

关键词： the Last Glacial Period stratigraphic division heavy mineral East China Sea fuzzy C-meanscluster

geoscience Frontiers 2015 Annual Convention

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geoscience Frontiers 2016年第2期7卷 295-296页

作者： Fei Gao Lily Wang Yongqiang Yang Mudan Yin geoscience Frontiers Journal CenterChina University of Geosciences Beijing

The 2015 geoscience Frontiers Annual Convention was held in Beijing, China during October 29, 2015 hosted by China University of geosciences, Beijing （Fig. 1）. This convention assembled earth scientists from 5 countries, including Australia （Prof. Franco Pirajno）, China （several delegates）, Germany （Prof. Daniel Harlov）, Italy （Prof. Carlo Doglioni）, Norway （Dr. Mathew Domeier）, South Korea （Prof. S. Kwon） and United States （Prof. Richard Goldfarb）, along with representatives from Elsevier （Beijing）.

关键词： Co GSF

geoscience Frontiers 2018 Annual Convention

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geoscience Frontiers 2019年第2期10卷 787-788页

作者： Fei Gao Lily Wang geoscience Frontiers Journal CenterChina University of Geosciences(Beijing)

The 2018 geoscience Frontiers Annual Convention was held at the China University of geosciences(Beijing),China,during September 20,2018(Fig.1).This convention assembled earth scientists from five countries,including Australia(*** Spencer),India(***),USA(*** Damian Nance and *** Meert),UK(*** Roberts),Turkey(*** Eyuboglu),China,and also representative from Elsevier(Beijing).

关键词： earth scientists