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A potential giant gallium deposit hosted in the tailing dam of the Fankou Zn-Pb deposit in northern Guangdong Province, South China
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作者 Peng-peng Yu Zhao-bin Hu +6 位作者 Yi Zheng Lan-xuan Guo Shi-yuan Ouyang Gui-qiang Yuan Shang-zhou Chen Cheng-ming Wang Xi Chen 《China Geology》 CAS CSCD 2024年第1期157-160,共4页
1.Objective The Fankou giant zinc(Zn)-lead(Pb)deposit in Guangdong Province is well-known for its huge reserves of over 10 Mt(million ton)Zn+Pb metals and high ore-grade with Zn+Pb exceeding 15%(Guangdong Fankou Depos... 1.Objective The Fankou giant zinc(Zn)-lead(Pb)deposit in Guangdong Province is well-known for its huge reserves of over 10 Mt(million ton)Zn+Pb metals and high ore-grade with Zn+Pb exceeding 15%(Guangdong Fankou Deposit Investigation Group,1980;Zhu XY et al.,2017).After 60 years of exploration and exploitation,the deposit has accumulated millions of tons of tailings.One interesting question is that what components are hosted in these tailings,and whether some key and critical metals such as gallium and germanium are extremely enriched and worth further comprehensive utilization.This motivated us to conduct an integrated set of field investigation,sampling,major-trace element analyses and reserve assessments about the Fankou tailings.In this contribution,we discover that the tailings contain a variety of metal elements such as zinc,lead and gallium with comprehensive utilization potential.These data can act as a scientific guidance for further exploration and utilization of the Fankou tailings,and aid to enhance the utilization efficiency of the key mineral resource in China.Our study also provide demonstration for future green mine construction in China. 展开更多
关键词 DEPOSIT comprehensive guangdong
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血红蛋白变异体Hb Fukuyama和Hb North Manchester干扰糖化血红蛋白检测2例报道
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作者 许楠 郑丽红 +5 位作者 薛丽 郭智 张艳 张彦平 耿燕 李友琼 《检验医学》 CAS 2024年第11期1128-1130,共3页
糖化血红蛋白(glycated hemoglobin A1c,HbA_(1c))可反映患者近2~3个月的血糖控制情况[1]。美国糖尿病协会(American Diabetes Association,ADA)在2010年就推荐将HbA_(1c)≥6.5%作为糖尿病的补充诊断标准[2]。血红蛋白(hemoglobin,Hb)... 糖化血红蛋白(glycated hemoglobin A1c,HbA_(1c))可反映患者近2~3个月的血糖控制情况[1]。美国糖尿病协会(American Diabetes Association,ADA)在2010年就推荐将HbA_(1c)≥6.5%作为糖尿病的补充诊断标准[2]。血红蛋白(hemoglobin,Hb)病是珠蛋白基因发生突变引起的一组溶血性遗传性疾病[3]。 展开更多
关键词 血红蛋白变异体 Hb Fukuyama Hb north Manchester 糖化血红蛋白 高效液相色谱法
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Geochemical Characteristics and Genesis of the Luxi-Xianrenzhang Diabase Dikes in Xiazhuang Uranium Orefield, Northern Guangdong Province 被引量:14
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作者 LING Hongfei SHEN Weizhou +5 位作者 DENG Ping JIANG Shaoyong JIANG Yaohui YE Haimin PU Wei TAN Zhengzhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期497-506,共10页
The Luxi-Xianrenzhang diabase dikes were emplaced into the eastern part of the Guidong composite granitoids in northern Guangdong Province at the end of the Early Cretaceous. They show tholeiitic features, enrichment ... The Luxi-Xianrenzhang diabase dikes were emplaced into the eastern part of the Guidong composite granitoids in northern Guangdong Province at the end of the Early Cretaceous. They show tholeiitic features, enrichment in large ion lithophile elements, slight enrichment in light rare earth elements, depletion in Zr and Hf, and basically no depletion in Nb and Ta and no Eu anomaly. They are similar to intraplate basalt in terms of trace element characteristics. They have high εNd(t) values (3.6-4.9), initial ^87Sr/^86Sr ratios (0.70530-70641) and δ^18O values and Dupal anomaly of Pb isotope compositions. Their Sr-Nd, Pb-Sr, Pb-Nd and Pb-Pb isotopes plot between DMM and EMII, with Pb similar to EMII, Nd relatively close to DMM and Sr in between. This profile suggests that the diabase dikes studied were derived from partial melting of a mantle source that had been subjected to metasomatism by fluids originated from a subduction zone under a tectonic environment of crustal extension and lithosphere thinning in the late Yanshanian. 展开更多
关键词 GEOCHEMISTRY main and trace elements Nd-Sr-Pb-O isotopes diabase dikes guangdong
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Late Paleozoic Fluid Systems and Their Ore-forming Effects in the Yuebei Basin,Northern Guangdong,China 被引量:6
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作者 DENG Jun YANG Liqiang +4 位作者 SUN Zhongshi WANG Jianping WANG Qingfei CHENG Xueming ZHOU Yinghua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第5期673-687,共15页
Based on detailed and systematic researches of the geology of ore deposits, fluid inclusions and isotope geochemistry etc., and regarding the Late Paleozoic fluid system of the Yuebei Basin as an integrated object in ... Based on detailed and systematic researches of the geology of ore deposits, fluid inclusions and isotope geochemistry etc., and regarding the Late Paleozoic fluid system of the Yuebei Basin as an integrated object in this paper, we have revealed the temporo-spatial evolution law of the basin's fluid system and discussed its ore-forming effects by simulating and analyzing the distribution of ore-forming elements, the fluid thermodynamics and dynamics of evolution processes of this basin. The results show that Late Paleozoic ore-forming fluid systems of the Yuebei Basin include four basic types as follows. (1) The sea floor volcanic-exhalation system developed during the rapid basin slip-extension stage in the Mid-Late Devonian, which affected the Dabaoshan region. It thus formed the Dabaoshan-type Cu-Pb-Zn-Fe sea floor volcanic-exhalation sedimentary deposits. (2) The compaction fluid system developed during the stable spreading and thermal subsidence-compression stage of the basin in the Mid-Late Devonian. The range of its effects extended all over the whole basin. It resulted in filling-metasomatic deposits, such as the Hongyan-type pyrite deposits and pyrite sheet within the Fankou-type Cu-Pb-Zn-S deposits. (3) The hot water circulation system of sea floor developed during the stage of basin uplifting and micro-aulacogen from the late Late Carboniferous to Middle Carboniferous. The range of its effects covered the Fankou region. It thus formed MVT deposits, such as the main orebody of the Fankou-type Pb-Zn-S deposits. (4) The gravity fluid system developed during the stage of fold uplifting and the basin closed from Middle Triassic to Jurassic, forming groundwater hydrothermal deposits, e.g. the veinlet Pb-Zn-calcite orebodies of the Fankou-type Pb-Zn- S deposits. Migration and concentration of the ore-forming fluids were constrained by the state of temporo-spatial distribution of its fluid potential. Growth faults not only converged the fluids and drove them to move upwards, but also the fluids often crossed the faults to the edges of the basin at the bottom of these faults and the lithologic interfaces, and even migrated to the basin's edges from top to bottom along the faults, which may be one of the basic reasons for the stratabound deposits to cluster mainly along the contemporaneous faults on the inner border of the basin. The superposed mineralization resulting from the multi-stage activity of contemporaneous faults and ore-forming fluid systems in the basin may be one of the key factors for forming superlarge ore deposits. 展开更多
关键词 fluid system stratabound deposit Late Paleozoic Yuebei Basin guangdong
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Statistical Approach for Classification of Dinosaur Eggs from the Heyuan Basin at the Northeast of Guangdong Province 被引量:1
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作者 Kohei TANAKA LU Junchang +4 位作者 LIU Yi HUANG Zhiqing Yoshitsugu KOBAYASHI HUANG Dong Darla K. ZELENITSKY 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期294-303,共10页
The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, ou... The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, outer surface texture, and shell thickness) of 461 eggs were analyzed using non-destructive techniques and subjected to statistical analyses in order to assess their diversity and taxonomic affinities. Three types (1, 2 and 3) of eggs were discerned based on shape and outer surface morphology. Type 1 eggs are spherical to ellipsoidal in shape and have a rough surface. Three subtypes (Type 1-A-l, l-A-2, and l-B) are apparent from scatter plots and cluster analyses of egg diameters and shell thickness. Type 2 eggs are elongate with linear ornamentation on the surface, and are comparable to eggs that belong to the oofamily Elongatoolithidae. Type 3 eggs are elongate with a smooth surface, and are assigned to the oofamily Prismatoolithidae. Macromorphological features of the various egg types suggest that Type 1 could have been laid by ornithischian, sauropod or therizinosaur dinosaurs, Type 2 by oviraptorids, and Type 3 by troodontids. This study represents the first comprehensive statistical analysis of macrofeatures of dinosaur eggs, and reveals taxonomic diversity in the dinosaurs that were laying eggs in the Upper Cretaceous Heyuan area heretofore unrecognized in skeletal remains. 展开更多
关键词 dinosaur egg Nanxiong Group Late Cretaceous Heyuan Basin guangdong China
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A Preliminary Study on the Red Beds in the Northern Heyuan Basin, Guangdong Province, China 被引量:1
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作者 ZHANG Xianqiu LU Junchang +3 位作者 BIAN Geguo QIU Licheng HUANG Dong YUAN Weiqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第5期598-604,共7页
The red beds of the northern Heyuan Basin (Guangdong Province, China) are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian F... The red beds of the northern Heyuan Basin (Guangdong Province, China) are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian Formation, and Zhenshui Formation of the Nanxiong Group, Shanghu Formation and Danxia Formation. The Nanxiong Group with relatively mature coarse clastic rocks attains about 2940 m in thickness. The Dafeng Formation is 837 m thick, consisting of conglomerates and sandy conglomerates; the Zhutian Formation, which is 1.200 m thick, consists of purplish red sandstone with gravels, poorly sorted sandstone, feldspathic quartzose sandstone banded granular conglomerate, siltstone, and sandy mudstone. The Zhutian Formation is rich in calcareous concretions. Heyuannia (Oviraptoridae) and turtle fossils were found in this formation. The Zhenshui Formation deposited to a thickness of 900 m consists of coarse sediments, including granular conglomerate, and gravelly sandstone with well developed cross-beddings; the Shanghu Formation, which is 820 m thick, consists of purplish red granular conglomerate coarse sandstone intercalated with fine si^tstone; the Danxia Formation characterized by the Danxia ~andform is composed of coarse c^astic gravels and sandy gravels. The lower part of the Nanxiong Group whence dinosaur eggs and derived oviraptorosaurs come, belongs to the Late Cretaceous. No fossils are found in the Shanghu Formation or the Danxia Formation, but their stratigraphic order of superposition on the Nanxiong Group clearly shows their younger age. 展开更多
关键词 Heyuan Basin red beds dinosaur eggs Heyuannia (Oviraptoridae) CRETACEOUS guangdong
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First Report LA-ICP-MS Zircon U-Pb Age of Early Jurassic Volcanic Rocks from Rencha Volcanic Basin, Northeast Guangdong Province, Southeastern China 被引量:3
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作者 YU Yushuai LOU Feng +2 位作者 DAI Pingyun GUO Fusheng YANG Qidi 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2036-2038,共3页
Objective Most scholars agreed that the tectonic setting of South China block(SBC)changed from Tethys during the Indosinian to Pacific tectonic regime in the Yanshanian.However,the specific change time for the trans... Objective Most scholars agreed that the tectonic setting of South China block(SBC)changed from Tethys during the Indosinian to Pacific tectonic regime in the Yanshanian.However,the specific change time for the transition is still in debate and the Triassic to Jurassic magmatic activity will provide a clue to better understanding the transition. 展开更多
关键词 PB northeast guangdong Province Southeastern China ICP MS
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Investigation and Analysis of Natural Environment of the Karst Mountain Areas in Northern Guangdong 被引量:1
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作者 LU Guan-yao 《Meteorological and Environmental Research》 2012年第5期43-44,48,共3页
[ Objective] The aim was to study the natural environment of Karst mountain areas in northern Guangdong. [ Method] Through the col- lection of topography, climate, soil and vegetation data in the Karst mountain areas ... [ Objective] The aim was to study the natural environment of Karst mountain areas in northern Guangdong. [ Method] Through the col- lection of topography, climate, soil and vegetation data in the Karst mountain areas of Northern Guangdong, combined with field investigation, the natural environment of Karst mountain areas in northern Guangdong was analyzed. [ Result] The Karst topography of the area is widely distributed. Most places were in subtropical climate zone, with high temperature and rainfall in the same period, and abundant precipitation. There was a large area of contiguous distribution of limestone with dissolution area. Vegetations included typical limestone evergreen and deciduous broadleaved mixed forest, limestone shrub and grassy slopes in mountain and hill. Limestone vegetation had typical limestone mixed evergreen broadleaf forest, limestone shrub, limestone hilly mountain grass slope. [ Conclusion] The study provided theoretical basis for the protection of natural environment of Karst mountain areas in northern Guangdong. 展开更多
关键词 GEOMORPHOLOGY CLIMATE SOIL VEGETATION northern guangdong China
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Petrogenesis of the Early Cretaceous Tiantangshan A-type Granite in northwestern Guangdong province, SE China and tectonic implications 被引量:2
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作者 JIA Ruya WANG Guochang +2 位作者 GENG Lin ZHANG Zhihui JIA Hongxiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期64-65,共2页
1 Introduction During the late Mesozoic times,the SE China is characterized by extensive magmatism and mineralization.The widely distributed granitoids with different(I-,S-and A-)types have been inferred to be closely... 1 Introduction During the late Mesozoic times,the SE China is characterized by extensive magmatism and mineralization.The widely distributed granitoids with different(I-,S-and A-)types have been inferred to be closely related to the large-scale polymetallic mineralization.The Nanling tungsten-tin polymetallic belt is endowed with considerable 展开更多
关键词 HIGH TYPE Petrogenesis of the Early Cretaceous Tiantangshan A-type Granite in northwestern guangdong province
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Spatio-temporal Variations in Plantation Forests'Disturbance and Recovery of Northern Guangdong Province Using Yearly Landsat Time Series Observations(1986-2015) 被引量:4
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作者 SHEN Wenjuan LI Mingshi WEI Anshi 《Chinese Geographical Science》 SCIE CSCD 2017年第4期600-613,共14页
Forest disturbance plays a vital role in modulating carbon storage,biodiversity and climate change.Yearly Landsat imagery from 1986 to 2015 of a typical plantation region in the northern Guangdong province of southern... Forest disturbance plays a vital role in modulating carbon storage,biodiversity and climate change.Yearly Landsat imagery from 1986 to 2015 of a typical plantation region in the northern Guangdong province of southern China was used as a case study.A Landsat time series stack(LTSS) was fed to the vegetation change tracker model(VCT) to map long-term changes in plantation forests' disturbance and recovery,followed by an intensive validation and a continuous 27-yr change analysis on disturbance locations,magnitudes and rates of plantations' disturbance and recovery.And the validation results of the disturbance year maps derived from five randomly identified sample plots with 25 km^2 located at the four corners and the center of the scene showed the majority of the spatial agreement measures ranged from 60% to 83%.A confusion matrix summary of the accuracy measures for all four validation sites in Fogang County showed that the disturbance year maps had an overall accuracy estimate of 71.70%.Forest disturbance rates' change trend was characterized by a decline first,followed by an increase,then giving way to a decline again.An undulated and gentle decreasing trend of disturbance rates from the highest value of 3.95% to the lowest value of 0.76% occurred between 1988 and 2001,disturbance rate of 4.51% in 1994 was a notable anomaly,while after 2001 there was a sharp ascending change,forest disturbance rate spiked in 2007(5.84%).After that,there was a significant decreasing trend up to the lowest value of 1.96% in 2011 and a slight ascending trend from 2011 to 2015(2.59%).Two obvious spikes in post-disturbance recovery rates occurred in 1995(0.26%) and 2008(0.41%).Overall,forest recovery rates were lower than forest disturbance rates.Moreover,forest disturbance and recovery detection based on VCT and the Landsat-based detections of trends in disturbance and recovery(LandT rendr) algorithms in Fogang County have been conducted,with LandT rendr finding mostly much more disturbance than VCT.Overall,disturbances and recoveries in northern Guangdong were triggered mostly by timber needs,policies and decisions of the local governments.This study highlights that a better understanding about plantations' changes would provide a critical foundation for local forest management decisions in the southern China. 展开更多
关键词 plantation Landsat dense time series remote sensing forest disturbance and recovery driving forces northern guangdong
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Geochemistry of rare-earth elements in shallow groundwater, northeastern Guangdong Province, China 被引量:5
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作者 YUAN Jianfei MAO Xumei +2 位作者 WANG Yanxin DENG Zhide HUANG Leihui 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2014年第1期53-64,共12页
Shallow groundwater and hot springs were collected from northeastern Guangdong Province, Southeast China, to determine the concentrations and fractionation patterns of rare-earth elements(REE). The results show that t... Shallow groundwater and hot springs were collected from northeastern Guangdong Province, Southeast China, to determine the concentrations and fractionation patterns of rare-earth elements(REE). The results show that the La, Ce and Nd of REEs are abundant in groundwater and rock samples, and the ∑REE contents in groundwater and rock samples range from 126.5 to 2875.3 ng/L, and 79.44 to 385.85 mg/L, respectively. The shallow groundwater has slightly HREE-enriched PAAS-normalized patterns. However, the granitic rocks PAAS-normalized patterns, with remarkable negative Eu anomalies, are different from that of shallow groundwater. The enrichment of HREE is considered to be controlled by REE complexation and readsorption for most groundwater has Ce and Eu positive anomalies. The Ce and Eu anomalies in groundwater are controlled by redox conditions. Moreover, the Fe-contain sediments dissolution and/or the reduction of Fe oxyhydroxides are another factor contributing to Ce anomalies. The Eu anomalies in groundwater are controlled by the preferential mobilization of Eu2+ during water-rock interaction compared to Eu3+. 展开更多
关键词 浅层地下水 稀土元素 中国东南部 地球化学 粤东北 氧化还原条件 地下水控制 Ce异常
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Distribution Patterns of Major and Trace Elements and Provenance of Surface Sediments on the Continental Shelf off Western Guangdong Province and Northeastern Hainan Island
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作者 GE Qian XUE Z. George +3 位作者 YE Liming XU Dong YAO Zhigang CHU Fengyou 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第4期849-858,共10页
A coupled approach based on grain size and geochemical elements is used to trace the provenance of surface sediments and to confirm the distribution patterns of grain size and elements on the continental shelf off wes... A coupled approach based on grain size and geochemical elements is used to trace the provenance of surface sediments and to confirm the distribution patterns of grain size and elements on the continental shelf off western Guangdong Province and northeastern Hainan Island. The mean grain size ranges from 0.05 φ to 7.28 φ with a mean value of 5.60 φ. The average concentra- tions of major elements descend in the order of SiO2 > Al2O3 > CaO > Fe2O3 > K2O > MgO > Na2O > TiO2 > P2O5 > MnO, while those of trace elements exhibit a descending order of Sr > Rb > Zn > V > Cr > Pb > Ni > Cu > As > Cd. On the basis of the distribution patterns of elements and results of statistical analysis, the study area is classified into three zones. Zone I locates on the continental shelf off western Guangdong Province, and the sediments are mainly from Pearl River, Taiwan Residents rivers, and small rivers nearby. Zone II locates in the eastern exit of Qiongzhou Strait and the coastal area off Leizhou Peninsula, and the sediments are mainly from the ero- sion products of Qiongzhou Strait and Hainan Island. Zone III locates off the eastern Hainan Island and the continental shelf deeper than 50 m isobaths, and the sediments are mainly from Hainan Island and coral reef. The influence from open water should also be considered. Results indicate that the grain size is the main controlling factor for major and trace element contents and that anthropo- genic impact and biological activity also play an important role in the distribution of these elements. 展开更多
关键词 grain size GEOCHEMICAL elements WESTERN guangdong Province northEASTERN HAINAN Island controlling factor
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Evaluation on Soil Heavy Metal Pollution around Tailing Areas: A Case Study of Ag-Sb Deposit in Northeastern Guangdong
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作者 Deliang LIU Kaifeng WANG +1 位作者 Qihe YANG Qin Zhu 《Asian Agricultural Research》 2015年第9期54-57,共4页
In October 2012,an evaluation using potential ecological hazard risk index was carried out on soil heavy metal pollution around AgSb deposit tailing areas in northeastern Guangdong. Results indicate that( i) soil heav... In October 2012,an evaluation using potential ecological hazard risk index was carried out on soil heavy metal pollution around AgSb deposit tailing areas in northeastern Guangdong. Results indicate that( i) soil heavy metal pollution is mainly Cd-Ni compound pollution,including Cd content 0. 31- 2. 66 mg / kg( average content is 1. 11 mg / kg),the situation of exceeding standard is serious( the rate of exceeding standard is 100%); the total potential ecological hazard risk index( RI) is between 50 and 300,and it is moderate pollution;( ii) in soil heavy metal content,only Ni and Cu are positively correlated. Since there is certain degree of Ni pollution in this deposit,the synergetic effect of Cu and Ni may deteriorate Ni pollution. 展开更多
关键词 Ag-Sb DEPOSIT in northEASTERN guangdong HEAVY meta
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Overwintering of Rana dybowskii in Northern Guangdong′s Mountainous Areas
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作者 YU Chunosheng YANG Jian-chun CHEN Xiao-feng 《Animal Husbandry and Feed Science》 CAS 2010年第10期33-35,共3页
[ Objective] To understand the overwintering of Rana dybowskii under four overwintering modes in northern Guangdong's mountainous areas. [Method] The overwintering management of Rana dybowskii was performed under fou... [ Objective] To understand the overwintering of Rana dybowskii under four overwintering modes in northern Guangdong's mountainous areas. [Method] The overwintering management of Rana dybowskii was performed under four overwintering modes which were outdoor overwintering in water-land, outdoor overwintering in water, indoor overwintering in dryness, and indoor overwintering in freezer, respectively. The time, temperature and overwintering status were recorded. The Rana dybowskii in each group was weighed before and after overwintering, and the body weight loss and the survival rate were calculated. [ Result] Under the outdoor overwintering in water-land, outdoor overwintedng in water, indoor overwintering in dryness, and indoor overwintering in freezer, the survival rate of Rana dybowskii was 40.0%, 41.5%, 82.0% and 84.5%, respectively. [Conclusion] The temperature, overwintering mode and fatness are the important factors affecting the safe overwintering of Rana dybowskii in northern Guangdong. 展开更多
关键词 Rana dybowskii northern guangdong Overwintering mode TEMPERATURE Relative fatness
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Analysis on Hydrogeochemical Characteristics and Their Temporal and Spatial Variation in the Karst Catchment of Lianjiang River,Northern Guangdong Province
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作者 Zhou Chen Xizhi Wang +3 位作者 Baosheng Li Gongcou Guan Zhaoxiong Liang Jun Wang 《Meteorological and Environmental Research》 CAS 2013年第11期35-43,共9页
[ Objective] The study aimed to discuss the hydrogeochemical features and their temporal and spatial variation in the karst catchment of Lianjiang River, northem Guangdong Province. [ Method] Water samples were collec... [ Objective] The study aimed to discuss the hydrogeochemical features and their temporal and spatial variation in the karst catchment of Lianjiang River, northem Guangdong Province. [ Method] Water samples were collected from 10 sub-drainages of Lianjiang River in July of 2012 and January of 2013, and then major chemical ions in tributaries of Xingzi River and Tongguanshui River were analyzed in detail to discuss the hydrochemistry type, spatial and temporal distribution and its causes of formation in Lianjiang River basin. [ Result] Among chemical ions in the wa- ter samples, Ca2. and HCO^- were dominant in Lianjiang River, accounting for over 70% and 80% of total concentrations of cations and anions re- spectively, followed by Mg2+ and SO24-. The concentrations of most major ions were higher in winter than those in summer except SO4^2- concentra- tion was much higher in summer than that in winter, which was related to anthropogenic factors. From hydrochemical types, it is seen that HCO3-- Ca2+ type in summer and HCO3--Ca2+ ~ Mg2. type in winter were dominant in Lianjiang River, followed by the HCO3--SO4^2- · Ca2+ type, and only two samples of Xingzi River belonged to HCO3--Ca2+ Mg2· Na+ type in winter. The spatial distribution regularity of chemical ions was not obvi- ous in the 10 sub-drainages of Lianjiang River. The concentrations of chemical ions changed greatly in the upper reaches but slightly in the lower reaches of Xingzi River catchment. The concentrations of chemical ions were steady in Tongguanshui River catchment with a smaller area, and it was a little higher in the upper reaches than those in the lower reaches. [ Conclusion] Natural processes, such as lithological heterogeneities and at- mospheric precipitation, contributed to the chemical composition of Lianjiang River catchment, northem Guangdong Province. 展开更多
关键词 northern guangdong Province Uanjiang River Ion concentration Spatial and temporal variation Hydrochemical types
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Organic Geochemistry of Lead-Zinc Polymetallic Deposits, Northern Guangdong 被引量:1
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作者 李兆麟 郭洪中 雷丽宏 《Chinese Journal Of Geochemistry》 EI CAS 1997年第4期330-335,共6页
The characters of organic matter in rocks and ores in the Fankou and Dabaoshan deposits are systematically studied with regard to their implications for mineralization. The results show that kerogens in this area fall... The characters of organic matter in rocks and ores in the Fankou and Dabaoshan deposits are systematically studied with regard to their implications for mineralization. The results show that kerogens in this area fall mainly into the plutonism field in Van Krevelen’s diagram.Reflectivity of the organic substance was measured to be 3. 06% (Fankou) and 1. 67% (Dabaoshan) , corresponding to the paleo-geotemperatures of 232℃ and 184℃ respectively.The same types of porphyrins and hydrocarbons were recognized in the rocks and ores and hydrocarbon-bearing inclusions are widespread in quartz and calcite, particularly in Dabaoshan. It is thought that the organic matter must have played a critical role in diagenesis and metallization in these deposits and that the hydrothermal solution was most 1ikely to be the type of water-oil hot brine. 展开更多
关键词 有机地球化学 锌矿床 成矿作用 昆仑山 广东
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A Physics-informed Deep-learning Intensity Prediction Scheme for Tropical Cyclones over the Western North Pacific 被引量:1
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作者 Yitian ZHOU Ruifen ZHAN +4 位作者 Yuqing WANG Peiyan CHEN Zhemin TAN Zhipeng XIE Xiuwen NIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1391-1402,共12页
Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a ti... Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a time-dependent theory of TC intensification,termed the energetically based dynamical system(EBDS)model,together with the use of a long short-term memory(LSTM)neural network.In time-dependent theory,TC intensity change is controlled by both the internal dynamics of the TC system and various environmental factors,expressed as environmental dynamical efficiency.The LSTM neural network is used to predict the environmental dynamical efficiency in the EBDS model trained using besttrack TC data and global reanalysis data during 1982–2017.The transfer learning and ensemble methods are used to retrain the scheme using the environmental factors predicted by the Global Forecast System(GFS)of the National Centers for Environmental Prediction during 2017–21.The predicted environmental dynamical efficiency is finally iterated into the EBDS equations to predict TC intensity.The new scheme is evaluated for TC intensity prediction using both reanalysis data and the GFS prediction data.The intensity prediction by the new scheme shows better skill than the official prediction from the China Meteorological Administration(CMA)and those by other state-of-art statistical and dynamical forecast systems,except for the 72-h forecast.Particularly at the longer lead times of 96 h and 120 h,the new scheme has smaller forecast errors,with a more than 30%improvement over the official forecasts. 展开更多
关键词 tropical cyclones western north Pacific intensity prediction EBDS LSTM
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Genesis of LCT Pegmatites during Early Paleozoic Orogeny of the North Qinling Orogenic Belt,China:Emplacement Conditions and Structural Control 被引量:1
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作者 CEN Jubiao FENG Yonggang +6 位作者 LIANG Ting WANG Mengxi ZHANG Jianxin TAN Xijuan ZHANG Jie GAO Jinggang HE Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1226-1243,共18页
The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we inv... The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we investigated it combining pegmatite orientation measurement with oxygen isotope geothermometry and fluid inclusion study.The orientations of type A1 pegmatites(P_(f)<σ_(2))are predominantly influenced by P-and T-fractures due to simple shearing in Shiziping dextral thrust shear zone during D_(2)deformation,whereas type A2 pegmatites(contemporaneous with D_(4))are governed by hydraulic fractures aligned with S_(0)and S_(0+1)stemming from fluid pressure(P_(f)<σ_(2)).Additionally,type B pegmatites(P_(f)≤σ_(2))exhibit orientations shaped by en echelon extensional fractures in local ductile shear zones(contemporaneous with D_(3)).The albite-quartz oxygen isotope geothermometry and microthermometric analysis of fluid inclusions in elbaites from the latest pegmatites(including types B and A2)suggest that the crystallization P-T for late magmatic and hydrothermal stages are 527.5-559.2℃,320℃,3.1-3.6 kbar and 2.0 kbar,respectively.Our observations along with previous studies suggest that the genesis of the LCT pegmatites was a long-term,multi-stage event during early Paleozoic orogeny(including the collision stage)of the NQB,and was facilitated by various local fractures. 展开更多
关键词 LCT pegmatite emplacement mechanism emplacement condition oxygen isotope geothermometry fluid inclusion north Qinling orogenic belt
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Mineral Chemical Characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in Northern Guangdong, China: Constraint on the Magmatic Source
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作者 ZHONG Fujun PAN Jiayong +2 位作者 LIU Guoqi LIU Wenquan QI Jiaming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期109-110,共2页
1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Gu... 1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Guidong granite 展开更多
关键词 China Constraint on the Magmatic Source Mineral Chemical Characteristics of Gabbro-diorite for Shulouqiu Uranium Deposit in northern guangdong
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Spatial Distribution Characteristics of Intercepted Rainwater on Rock Desertified Shrub Slopes in the Northern Guangdong Region 被引量:1
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作者 XinghuWei Xizhen Xu Li Lei 《地球科学期刊(中英文版)》 2013年第2期71-80,共10页
关键词 地球科学 天文学 天文观测 机构
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