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A Brief Discussion on the Development of the Silk-Weaving Industry Along the “Southern Silk Road” in Yunnan 被引量:1
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作者 Lin Kaiqiang 《Contemporary Social Sciences》 2024年第1期18-33,共16页
Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative l... Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative leap as skilled silk craftsmen from the Bashu area migrated to Yunnan and introduced mulberry planting,silkworm breeding,and advanced silk-weaving techniques from Sichuan to the region.Consequently,people in Yunnan gradually acquired expertise in brocade weaving and embroidery.Many even mastered complex silk-weaving techniques.The development and progress of the silk-weaving industry in the ancient Yunnan region were intricately linked to the economic function and value of silk as both a commodity and currency along the“Southern Silk Road.”The local government in ancient Yunnan was greatly motivated by the economic interests brought by the development of silk-related industries and recognized the significance of developing the local silk industry.They even initiated a campaign to capture skilled silk craftsmen from Sichuan,aiming to foster the growth of the silk-weaving industry in Yunnan.After years of dedicated efforts from the local government in ancient Yunnan,the region emerged as a significant hub for silk production along China’s ancient“Southern Silk Road.”Despite the devastation caused by the wars in other parts of the country,Yunnan’s silk industry continued to thrive and provide ample silk products to sustain trade along this renowned route.In the contemporary era,amidst the decline of the silk-weaving industry in eastern China,Yunnan has proposed an industrial development strategy known as“relocating the silk-weaving industry from east to west.”This involves introducing advanced silk production techniques from the eastern regions into Yunnan to enhance and enrich its local silk industry,thereby establishing it as a traditional national sector and securing a competitive position within the global silk market.The historical experience of Yunnan’s silk industry demonstrated that economic development opportunities can only be seized through proactive endeavors rather than passive anticipation.The modern Yunnan silk industry,which upholds its historical traditions,continues to actively engage in international high-end technical cooperation,thus ensuring the enduring vitality of the ancient“Southern Silk Road.” 展开更多
关键词 southern Silk Road Bashu area YUNnan silk-weaving technique
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Garnet and Zircon U-Pb Geochronology and Geochemistry Reveal Genesis of the Dafang Au-Pb-Zn-Ag Deposit,Southern Hunan
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作者 JIANG Hua KONG Hua +4 位作者 LIU Biao TAN Fucheng QIN Yixue HUANG Jingang ZHU Yu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期717-735,共19页
Garnet is a primary mineral in skarn deposits and plays a significant role in recording copious mineralization and metallogenic information.This study systematically investigates the geochemistry and geochronology of ... Garnet is a primary mineral in skarn deposits and plays a significant role in recording copious mineralization and metallogenic information.This study systematically investigates the geochemistry and geochronology of garnet and zircon in the Dafang Au-Pb-Zn-Ag deposit,which represents prominent gold mineralization in southern Hunan,China.Garnet samples with distinct zoning patterns and compositional variations were identified using various analytical techniques,including Backscattered Electron(BSE)imaging,Cathodoluminescence(CL)response,textural characterization,and analysis of rare-earth elements(REE),major contents,and trace element compositions.The garnet was dated U-Pb dating,which yielded a lower intercept age of 161.06±1.93 Ma.This age is older than the underlying granodiorite porphyry,which has a concordia age of 155.13±0.95 Ma determined by zircon U-Pb dating.These results suggest that the gold mineralization may be related to the concealed granite.Two groups of garnet changed from depleted Al garnet to enriched Al garnet,and the rare earth element(REE)patterns of these groups were converted from light REE(LREE)-enriched and heavy REE(HREE)-depleted with positive europium(Eu)anomalies to medium REE(MREE)-enriched from core to rim zoning.The different REE patterns of garnet in various zones may be attributed to changes in the fluid environment and late superposition alteration.The development of distal skarn in the southern Hunan could be a significant indicator for identifying gold mineralization. 展开更多
关键词 garnet and zircon U-Pb dating LA-ICP-MS mapping Dafang southern Hunan
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Petrogenesis of skarn in Shizhuyuan W-polymetallic deposit, southern Hunan,China:Constraints from petrology,mineralogy and geochemistry 被引量:2
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作者 成永生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第6期1676-1687,共12页
Skarn is the main altered rock type and is of great importance to mineralization and ore-prospecting in the Shizhuyuan area of Hunan province, China. Its features of petrography, mineralogy and geochemistry were st... Skarn is the main altered rock type and is of great importance to mineralization and ore-prospecting in the Shizhuyuan area of Hunan province, China. Its features of petrography, mineralogy and geochemistry were studied systematically. The results show that the skarn mainly consists of garnet skarn, secondary wollastonite-garnet skarn, tremolite-clinozoisite skarn, and few wolframine garnet skarn, idocrase-garnet skarn and wollastonite skarn with granoblastic texture, granular sheet crystalloblastic texture, and massive structure, disseminated structure, mesh-vein structure, comb structure, and banded structure. And, it is mainly composed of garnet, fluorite, chlorite, hornblende, epidote, tremolite, plagioclase, biotite, muscovite, plagioclase, quartz, idocrase, and calcite and so on. The chemical components mainly include SiO2, Al2O3, Fe2O3, MgO and CaO, and the trace elements and REEs consist of Li, Be, V, Co, Zn, Ga, Rb, Sr, Y, Ce, Nd, Pb and Bi, etc. And, the obvious fractionation exists between LREE and HREE, and it shows typical features of Nanling ore-forming granite for W?Sn polymetallic deposit. Skarn is derived from the sedimentary rock, such as limestone, mudstone, argillaceous rock, and few pelitic strips. It is affected by both Shetianqiao formation strata and Qianlishan granite during the diagenesis, indicating a strong reduction environment. The occurrence of skarn, whose mutation site is favorable to the mineralization enrichment, is closely related to the mineralization and prospecting. 展开更多
关键词 SKARN PETROGENESIS GEOCHEMISTRY Shizhuyuan W-polymetallic deposit southern Hunan
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Ramp facies in an intracratonic basin:A case study from the Upper Devonian and Lower Carboniferous in central Hunan,southern China 被引量:6
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作者 Longyi Shao Dongdong Wang Houan Cai Hao Wang Jing Lu Pengfei Zhang 《Geoscience Frontiers》 SCIE CAS 2011年第3期409-419,共11页
Detailed studies on Late Devonian to Early Carboniferous carbonate rocks in central Hunan, southern China have led to the recognition of 25 lithofacies which can be grouped into: (I) inner ramp peritidal platform, ... Detailed studies on Late Devonian to Early Carboniferous carbonate rocks in central Hunan, southern China have led to the recognition of 25 lithofacies which can be grouped into: (I) inner ramp peritidal platform, (2) inner ramp organic hank and mound, (3) mid ramp, (4) outer ramp, and (5) shelf basin facies associations. The peritidal platform facies association dominates the Zimenqiao Formation (Namurian A or late Datangian) and is characterized by gypsum and dolostone-containing sequences, indicating a peritidal platform environment. The other four facies associations dominate the Menggongao Formation (late Famennian), Liujiatang Formation (Tournaisian or Yangruanian), Shidengzi Formations (early Visean or early Datangian). Five upward-shallowing cycles were distinguished in these three Formations. The predominant facies associations developed in each Formation demonstrate an overall transgression-regression cycle in the Late Devonian to Early Carboniferous in central Hunan. The overall transgressive sequence was preserved in the Shaodong, Menggongao, and Liujiatang Formations, and the overall regressive sequence was preserved in the Liujiatang, Shidengzi, Ceshui and Zimenqiao Formations. 展开更多
关键词 Intracratonic basin Carbonate ramp southern China Lower Carboniferous Upper Devonian
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Provenance analysis of surface sediments in the Holocene mud area of the southern coastal waters off Shandong Peninsula,China 被引量:6
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作者 ZHANG Xiaobo BI Shipu +5 位作者 ZHANG Yong YANG Yuan LIU Shanshan KONG Xianghuai LI Xiaoyue CHU Hongxian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第5期124-133,共10页
The sedimentary record of mud areas is an important carrier of information on the Holocene evolution of marine environments. Based on fine interpretations of the shallow stratigraphic section data, a small mud deposit... The sedimentary record of mud areas is an important carrier of information on the Holocene evolution of marine environments. Based on fine interpretations of the shallow stratigraphic section data, a small mud deposit area has been found in the southern coastal waters off Shandong Peninsula. This mud area is mainly distributed in coastal waters north of Laoshantou to the vicinity of Rushan Estuary. Overall, it is parallel to the coastline and spreads in a banded pattern, gradually thinning from offshore to the sea. The isopach map of depth distribution is parallel with the shoreline, and the depocenter lies in coastal waters of the Aoshan Bay where the maximum thickness is up to 22.5 m. Accelerator mass spectrometry(AMS) ^(14)C dating shows that the mud area was formed in the Holocene. The test data of surface sediments from the mud area, including particle size, mineral characteristics, and rare earth element contents, are used in comparisons with the composition of materials from the major surrounding medium and small rivers flowing into the sea and the Huanghe(Yellow) River. In this paper, the sedimentary characteristics and provenance of the mud deposit area are discussed. The results show that the formation of this mud area resulted from the joint action of the Huanghe River and surrounding rivers flowing into the sea. 展开更多
关键词 southern coastal waters off Shandong Peninsula mud area provenance analysis
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Distribution characteristics of planktonic nano-and microalgae in the Prydz Bay and its adjacent Southern Indian Ocean,during austral summer 被引量:3
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作者 朱根海 刘子琳 +1 位作者 宁修仁 王敏 《Chinese Journal of Polar Science》 1994年第2期33-44,共12页
Nano- and microalgae samples were collected from 34 stations in the Prydz Bay and its adjacent Southern indian Ocean, Antarctica during a Period from December 1990 to January 1991. 122 taxa belonging to 40 genera 5 ph... Nano- and microalgae samples were collected from 34 stations in the Prydz Bay and its adjacent Southern indian Ocean, Antarctica during a Period from December 1990 to January 1991. 122 taxa belonging to 40 genera 5 phyla were identified. Among them diatom occupy 73%,dinoflagellates 20. 5%, the other species 6. 5 %. The average cell abundance of nano- and microalgae was 2551×104 cells/m3 in surface waters. The concentration of nano- and microalgae occurred in the Prydz Bay and its adjacent continental station Ⅳ 7 and northern water area between West Ice Shelf and Shackleton Ice Shelf (Stations Ⅶ 3, Ⅷ 1, Ⅷ 2, Ⅷ 3, Ⅸ 1, Ⅺ 1); and minimal abundance occurred in northwestern area of the Prydz Bay (some stations of section Ⅲ and Station Ⅳ 1-5). The average cell abundance of planktonic nano- and microalgae from net sample was 811. 62×104 cells/m3, and the concentration area occurred in the adjacent continent waters of the Prydz Bay (Stations Ⅳ 2, Ⅳ 4, Ⅳ 5, Ⅳ 7, Ⅴ 4 and Ⅴ 5) and northern area of the West Ice Shelf(Stations Ⅶ 1 and Ⅶ 3); low abundance occurred in eastern area of the Shackleton Ice Shelf (at each station of sections Ⅹ and Ⅺ ). For the vertical distribution of planktonic nano- and microalgae, the maximum value was usually found at the surface and above 50 m depth, and gradually decreased with the water depth from 100 m to 200 m. The relationship between planktonic nano-and microalgal abundance and Euphausia superba density and nutrient (nitrate,phosphate and silicate) contents were negative significance. 展开更多
关键词 planktonic nano- and microalga abundance DISTRIBUTION Antarctica Prydz Bay southern Indian Ocean
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BIOGEOGRAPHICAL IMPLICATIONS OF SOME PLANTSPECIES FROM A TROPICAL MONTANE RAIN FORESTIN SOUTHERN YUNNAN 被引量:2
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作者 ZHUHua 《Chinese Geographical Science》 SCIE CSCD 2004年第3期221-226,共6页
A pristine montane rain forest was recently discovered from Mengsong of Xishuangbanna in the southern Yunnan. It attracts botanists that many primitive plant taxa across various life forms were co-existed in the monta... A pristine montane rain forest was recently discovered from Mengsong of Xishuangbanna in the southern Yunnan. It attracts botanists that many primitive plant taxa across various life forms were co-existed in the montane rain forest. In order to know the biogeography of the montane rain forest, distribution patterns of some species of biogeographical importance from the montane forest were enumerated and their biogeographical implications were discussed with geological explanation. It was concluded that the montane rain forest in the southern Yunnan has strong affinity to montane rain forests in Sumatra or Southeast Asia in broad sense. It was tentatively suggested that Sumatra could be once connected to Myanmar and drifted away due to northward movement of continental Asia by bumping of India plate. 展开更多
关键词 BIOGEOGRAPHY montane rain forest southern Yunnan
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IMPACT OF SSTA OF SOUTHERN HEMISPHERE ON FLOOD SEASON PRECIPITATION ANOMALIES IN YUNNAN 被引量:1
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作者 杨竹云 杨素雨 +2 位作者 严华生 张瑾文 古书鸿 《Journal of Tropical Meteorology》 SCIE 2015年第3期255-264,共10页
Based on the reanalysis data of monthly mean global SST and wind from the NCEP/NCAR and the observation data of rain seasons in 124 stations of Yunnan province from 1961 to 2006, we applied the analytical methods of c... Based on the reanalysis data of monthly mean global SST and wind from the NCEP/NCAR and the observation data of rain seasons in 124 stations of Yunnan province from 1961 to 2006, we applied the analytical methods of correlation analysis and composite analysis and a significance testing method to two sets of samples of average differences. The goal is to investigate into the influence of the Southern Hemispheric(SH) SST on the summer precipitation in Yunnan from January to May so as to identify the key time and marine regions. Physical mechanisms are obtained by analyzing the influence of sea level wind and the key marine regions on the precipitation during Yunnan's rain season.Results show that there is indeed significant relationship between the SST in SH and summer precipitation in Yunnan.The key areas for influencing the summer precipitation are mainly distributed in a region called "West Wind Drift" in the SH, including the Southeast Indian, southern Australia, west coast of eastern Pacific off Chile, Peru and the southwest Atlantic Magellan. Besides, the most significant marine region is the west coast of Chile and Peru(cold-current areas of the eastern Pacific). Diagnostic analysis results also showed that monsoons in the Bay of Bengal, a cross-equatorial flow in the Indian Ocean near the equator and southwest monsoon in India weaken during the warm phase of the Peruvian cold current in the eastern Pacific. Otherwise, they strengthen. 展开更多
关键词 SST of southern Hemisphere YUNnan precipitation anomalies during rain season key marine area West Wind Drift
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Research on Southern Herbs and Li Medical Plants in Hainan 被引量:2
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作者 张浪 任军方 云勇 《Agricultural Science & Technology》 CAS 2014年第10期1770-1773,共4页
The current situation, development advantages and presenting problems of southern herbs and Li medical plants in Hainan Province were analyzed in this pa-per. ln addition, some ideas and solutions were proposed, provi... The current situation, development advantages and presenting problems of southern herbs and Li medical plants in Hainan Province were analyzed in this pa-per. ln addition, some ideas and solutions were proposed, providing a reference to government departments and investors. 展开更多
关键词 southern herb Li medical plant HAInan Development and utilization Problem and solution
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Dominant SST Mode in the Southern Hemisphere Extratropics and Its Influence on Atmospheric Circulation 被引量:1
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作者 Fei ZHENG Jianping LI +2 位作者 Fred KUCHARSKI Ruiqiang DING Ting LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第7期881-895,共15页
The variability in the Southern Ocean(SO) sea surface temperature(SST) has drawn increased attention due to its unique physical features; therefore, the temporal characteristics of the SO SST anomalies(SSTA) and... The variability in the Southern Ocean(SO) sea surface temperature(SST) has drawn increased attention due to its unique physical features; therefore, the temporal characteristics of the SO SST anomalies(SSTA) and their influence on extratropical atmospheric circulation are addressed in this study. Results from empirical orthogonal function analysis show that the principal mode of the SO SSTA exhibits a dipole-like structure, suggesting a negative correlation between the SSTA in the middle and high latitudes, which is referred to as the SO Dipole(SOD) in this study. The SOD features strong zonal symmetry, and could reflect more than 50% of total zonal-mean SSTA variability. We find that stronger(weaker) Subantarctic and Antarctic polar fronts are related to the positive(negative) phases of the SOD index, as well as the primary variability of the large-scale SO SSTA meridional gradient. During December–January–February, the Ferrel cell and the polar jet shift toward the Antarctic due to changes in the SSTA that could be associated with a positive phase of the SOD, and are also accompanied by a poleward shift of the subtropical jet. During June–July–August, in association with a positive SOD, the Ferrel cell and the polar jet are strengthened, accompanied by a strengthened subtropical jet. These seasonal differences are linked to the differences in the configuration of the polar jet and the subtropical jet in the Southern Hemisphere. 展开更多
关键词 extratropical sea surface temperature air–sea interaction southern Annular Mode
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Late Eocene–early Miocene provenance evolution of the Crocker Fan in the southern South China Sea 被引量:1
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作者 Yuchi Cui Lei Shao +3 位作者 Wu Tang Peijun Qiao Goh Thian Lai Yongjian Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期215-226,共12页
There are many large-scale Cenozoic sedimentary basins with plentiful river deltas,deep-water fans and carbonate platforms in the southern South China Sea.The Crocker Fan was deposited as a typical submarine fan durin... There are many large-scale Cenozoic sedimentary basins with plentiful river deltas,deep-water fans and carbonate platforms in the southern South China Sea.The Crocker Fan was deposited as a typical submarine fan during the late Eocene–early Miocene,and stretches extensively across the entire Sarawak–Sabah of the northern Borneo area.However,systematic analyses are still lacking regarding its sediment composition and potential source suppliers.No consensus has been reached yet on the provenance evolution and sedimentary infilling processes,which seriously impeded the oil-and-gas exploration undertakings.By combining with sedimentaryfacies identification,heavy mineral assemblages,elemental geochemistry and detrital zircon U-Pb dating,this paper aims to generalize an integrated analysis on the potential provenance terranes and restore source-to-sink pathways of the Crocker Fan.In general,the Crocker Fan was initially formed over the Cretaceous–lower/middle Eocene Rajang Group by an angular Rajang unconformity.The continual southward subduction of the protoSouth China Sea resulted in magmatic activities and subsequent regional deformation and thrusting along the Lupar Line in the northern Borneo.The lowermost Crocker sequence is featured by a thick conglomerate layer sourced from in-situ or adjacent paleo-uplifts.From the late Eocene to the early Miocene,the Crocker Fan was constantly delivered with voluminous detritus from the Malay Peninsula of the western Sundaland.The Zengmu Basin was widely deposited with delta plain and neritic facies sediments,while the Brunei-Sabah Basin,to the farther east,was ubiquitously characterized by turbiditic sequences.The Crocker Fan successions are overall thick layers of modest-grained sandstones,which formed high-quality reservoirs in the southern South China Sea region. 展开更多
关键词 source-to-sink analysis zircon U-Pb age submarine fan Malay Peninsula southern South China Sea
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Rare earth element(REE) geochemistry of different colored fluorites from the Baoshan Cu–Pb–Zn deposit, Southern Hunan,South China 被引量:1
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作者 Jinchuan Huang Jiantang Peng 《Acta Geochimica》 EI CAS CSCD 2022年第3期419-433,共15页
The Baoshan Cu–Pb–Zn deposit, located in the central part of the Qin–Hang belt in South China, is closely related to the granodiorite-porphyry. However, the characteristics and the source of the ore-forming fluid a... The Baoshan Cu–Pb–Zn deposit, located in the central part of the Qin–Hang belt in South China, is closely related to the granodiorite-porphyry. However, the characteristics and the source of the ore-forming fluid are still ubiquitous. According to the crosscutting relationships between veinlets and their mineral assemblages, three stages of hydrothermal mineralization in this deposit were previously distinguished. In this contribution, two different colored fluorites from the major sulfide mineralization stage are recognized:(1) green fluorites coexisting with Pb–Zn ores;and(2) violet fluorites coexisting with pyrite ores. Y/Ho ratios verify the green fluorites and violet fluorites were co-genetic. The fluorites display elevated(La/Yb)Nratios, which decrease from 1201 to 5710 for green fluorites to 689–1568 for violet fluorites, indicating that they precipitated at the early hydrothermal sulfide stage,and Pb–Zn ores crystallized earlier than pyrite ores. The similar Tb/La ratios of the fluorites also indicate that they precipitated at an early stage within a short time. From the green fluorites to violet fluorites, the total rare earth element(ΣREE)concentrationsdecreasefrom1052–1680 ppm to 148–350 ppm, indicating that the green fluorites precipitated from a more acidic fluid. The Eu/Eu*ratios increase from 0.17 to 0.30 for green fluorites to0.29–0.48 for violet fluorites, and the Ce/Ce* ratios decrease from 1.08–1.13 to 0.93–1.11, suggesting a gradual increase in oxygen fugacity(fO_(2)) and pH value of the mineralization fluid. Though the fluorites display similar REE patterns to the granodiorite-porphyry and limestone,the ΣREE concentrations of the fluorites are significantly higher than those of limestone and the granodiorite-porphyry, suggesting that an important undetected non-magmatic source is involved to provide sufficient REE for fluorites. The most plausible mechanism is fluid mixing between magma fluid and an undetected non-magmatic fluid. 展开更多
关键词 Trace element geochemistry REE Fluorite Baoshan Cu–Pb–Zn deposit southern Hunan South China
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Geophysical Features of the Ore-Controlling Fault in the Chang'an Gold Deposit, Southern Yunnan Province 被引量:1
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作者 LI Hua ASKAR +4 位作者 ZHOU Yunman ZHANG Wei WU Wenxian ZHOU Yimin ZHOU Kuiwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第5期1771-1772,共2页
The Ailao Mountain is one of the most important metallogenic belts ofpolymetallic deposits in the Sanjiang region, southwestern China. Located in the southern segment of this metallogenic belt, the newly-discovered Ch... The Ailao Mountain is one of the most important metallogenic belts ofpolymetallic deposits in the Sanjiang region, southwestern China. Located in the southern segment of this metallogenic belt, the newly-discovered Chang'an gold deposit is large in scale (Fig. 1A), and has attracted much attention among geologists. The ore-hosted rocks in the district include the Late Ordovician Xiangyang Fm. sandstone and clastic rocks and the Early Silurian Kanglang Fm. dolomite. Affected by the multistage tectonic activities, stocks and dykes of lamprophyre, dolerite, syenite porphyry and orthoclasite are widely exposed, and the orebodies are in symbiosis with or crosscut the dyke rocks. 展开更多
关键词 GOLD southern Yunnan Province Geophysical Features of the Ore-Controlling Fault in the Chang’an Gold Deposit
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Late Quaternary Calcareous Nannofossils from the Offshore Sediments in southern Hongkong
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作者 HUANG Yongyang CHEN Fang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第2期242-247,共6页
Abstract Based upon the features of nannofossil composition, distribution, abundance and diversity, the fossil-bearing sediments exposed by five drill holes in the offshore area of southern Hongkong can be divided int... Abstract Based upon the features of nannofossil composition, distribution, abundance and diversity, the fossil-bearing sediments exposed by five drill holes in the offshore area of southern Hongkong can be divided into the upper Middle Pleistocene, the Upper Pleistocene and Holocene. There were two palaeoclimatic stages in the Holocene in this area according to fossil palaeoecologic and sedimentation analyses: the temperature-rising stage and the warm stage. The latter involves two temperature-falling periods, which could be the major factor causing sea-level fall during that time. 展开更多
关键词 nanNOFOSSIL Quaternary palacooceanography Lingdingyang southern Hongkong
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NEW EVIDENCES FOR THE FORMATION OF GRANITICROCKS BY REMELTING OF THE SIALCRUST IN SOUTHERN HUNAN
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作者 Peng Shenglin Yang Dejiang Lai JianqingShao Yongjun Yang Mu Chen Xu(Institute of Diwa Theory Metallogeny, Central South University ofTechnology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第1期22-24,共3页
Comparatively analyzing 47 REE distribution data of the Southern Hunan geosynclinal arkosesilicarenite and various period granitic rocks and the results of their partially melting experiment series in company with the... Comparatively analyzing 47 REE distribution data of the Southern Hunan geosynclinal arkosesilicarenite and various period granitic rocks and the results of their partially melting experiment series in company with the occurence and petrogeochemical features of various period granitic rocks, the authors suggest that all of the abovementioned salic rocks can be partially melt to produce granitic magma. 展开更多
关键词 salic CRUST REMELTING GRANITIC ROCK southern Hunan〖WT5BZ
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Abundance pattern of heterotrophic nanoflagellates in the southern Taiwan Strait
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作者 林元烧 曹文清 +1 位作者 罗文新 李少菁 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第3期415-422,共8页
The analysis of 103 samples collected quantitatively from the southern Taiwan Strait (22°4'-24°3'N, 117°'-119°9'E), China, in August 1997 indicates that the abundance of heterotroph... The analysis of 103 samples collected quantitatively from the southern Taiwan Strait (22°4'-24°3'N, 117°'-119°9'E), China, in August 1997 indicates that the abundance of heterotrophic nanoflagellates (HNF) ranges from 391 to 1 846 × 103 cell/dm3, with an average of 949 × 103 cell/dm3, and 96.2% of cells are in size of 2-22 um in all HNF met in the samples. The HNF cells are 9.83-45.79 μg/dm3 after conversion from cell number to carbon content, with an average of 22.82 μg/dm3. The HNF abundance is relatively low in comparison with other areas. The nitrogen and phosphorus nutrients of the water are lower than previous investigations, which may be caused by the El Nino. The biomass of HNF is higher in southern waters, where cell concentration is 3-5 folds higher than that in other waters, and nearly 2-fold as high as the average of the investigated areas. The HNF is mainly habitat in 0-30 m water layer. Both horizontal and vertical HNF distribution must be influenced by hy-drographical dynamic process to a great extent. Continuous in situ observations of HNF indicate the 24 h diurnal rhythm, with two peaks, one in night at one station (Station 9701) and one during the period of 12:00 - 24:00 at another (Station 9704). The factors controlling the diurnal variation of HNF are unclear, although vertical migration of HNF is obviously. 展开更多
关键词 Heterotrophic nanoflagellates abundance pattern the southern Taiwan Strait
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U-Pb Zircon Age, Geochemical and Sr-Nd Isotopic Constraints on the Age and Origin of the Granodiorites in Guilong, Southeastern Yunnan Province, Southern China
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作者 Shen Liu Ruizhong Hu +7 位作者 Caixia Feng Shan Gao Guangying Feng Youqiang Qi Tao Wang Ian M. Coulson Yuhong Yang Chaogui Yang 《Open Journal of Geology》 2012年第4期229-240,共12页
Post-collision felsic rocks in Southeastern Yunnan province contain granodiorites. U-Pb zircon ages, geochemical data and Sr-Nd isotopic data for these rocks are reported in the present paper. Laser ablation inductive... Post-collision felsic rocks in Southeastern Yunnan province contain granodiorites. U-Pb zircon ages, geochemical data and Sr-Nd isotopic data for these rocks are reported in the present paper. Laser ablation inductively coupled plasma mass spectrometry U-Pb zircon analyses yielded consistent age 252.5 ± 1.0 Ma for one sample of the felsic rocks. The granodiorites were characterized by variational and high (87Sr/86Sr)i, ranging from 0.7223 to 0.7236 and very low εNd (t) values from –29.1 to –30.4. In addition, these rocks are characterized by slight Eu negative anomalies, Nb, Ta, Ti and Sr negative anomalies on primitive mantle normalization spider. Geochemical and isotopic characteristics suggest that these rocks were derived from an enriched crust source. The granodiorites resulted from the fractionation of potassium feldspar, plagioclase and ilmenite or rutile. However, the granodiorites were unaffected by visible crustal contamination during ascent. As a result, the granodiorites may have been formed due to partial melting of crust-derived sedimentary rocks beneath southeastern Yunnan province, southern China. 展开更多
关键词 Granodiorites Age ORIGIN Southeastern YUNnan Province southern China
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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China 被引量:2
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作者 Wen-Long Dang Gang Gao +5 位作者 Xin-Cai You Ke-Ting Fan Jun Wu De-Wen Lei Wen-Jun He Yong Tang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期100-114,共15页
The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of th... The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu Sag.These crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep sag.During migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source rocks.These changes might alter source rock evaluations and oil-source correlation.Based on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu Sag.The source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate oil.Source rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped distribution.Furthermore,biomarker composition parameters indicate a higher thermal maturity than in-situ source rocks.Through a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin mudstone.This finding reminds us that the influence of migrated hydrocarbons must be considered when evaluating source rocks and conducting oil-source correlation. 展开更多
关键词 Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation southern Mahu Sag
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New insights into multiple provenances evolution of the Jurassic from heavy minerals characteristics in southern Junggar Basin, NW China
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作者 ZHOU Tianqi WU Chaodong +8 位作者 YUAN Bo SHI Zhongkui WANG Jialin ZHU Wen ZHOU Yanxi JIANG Xi ZHAO Jinyong WANG Jun MA Jian 《Petroleum Exploration and Development》 2019年第1期67-81,共15页
The method of random forest was used to classify the heavy mineral assemblages of 2 418 Jurassic samples in the southern Junggar Basin, and determine the distribution of the heavy mineral assemblages from the same pro... The method of random forest was used to classify the heavy mineral assemblages of 2 418 Jurassic samples in the southern Junggar Basin, and determine the distribution of the heavy mineral assemblages from the same provenance systems. Based on the analysis of heavy minerals assemblages, ZTR index, sedimentary characteristics, U-Pb zircon ages, whole-rock geochemical and paleocurrent direction analysis, the study reveals that five important provenances were providing sediments to the southern Junggar Basin in the Jurassic period: The North Tianshan(NTS), Central Tianshan(CTS), Bogda Mountains, Zhayier Mountains and Kalamaili Mountains. During the Early Jurassic, NTS-CTS, Kalamaili Mountains and Zhayier Mountains are primary provenances, Bogda Mountains started to uplift and supply clastic materials in the Middle Jurassic. There are three sedimentary area in the Jurassic of southern Junggar Basin: the western part, the central part and the eastern part. In the western part, the clastic materials of the Early Jurassic was mainly from NTS blocks and Zhayier Mountains, and the sediments were dominantly derived from the Zhayier Mountains during the Middle–Late Jurassic. In the central part, the main provenance of the Early Jurassic switched from NTS to CTS. In the Xishanyao Formation, the main source went back to NTS again. The NTS was the primary provenance during the sedimentary periods of Toutunhe Formation and Qigu Formation. In the eastern part, the contribution of CTS and Kalamaili Mountains were considered as major provenances in the Early Jurassic-Xishanyao Formation, small proportion of sediments were from NTS. The Bogda mountains uplifted and started to provide sediments to the Junggar Basin in the sedimentary period of Xishanyao Formation, and became the major source during the Toutunhe Formation period, with small amount of sediments from CTS. The provenance from CTS was hindered during the sedimentary period of Qigu Formation owing to the uplifting of the Bogda mountains, and the sediments were mainly from the Bogda mountains and NTS. 展开更多
关键词 southern JUNGGAR Basin JURASSIC source to sink system provenance heavy minerals ASSEMBLAGES random forest
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Differences in spring precipitation over southern China associated with multiyear La Ni?a events 被引量:1
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作者 Guangliang Li Licheng Feng +3 位作者 Wei Zhuang Fei Liu Ronghua Zhang Cuijuan Sui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期1-10,共10页
Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-... Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-normal precipitation during the first boreal spring, but above-normal precipitation during the second year. The difference in spring precipitation over southern China is correlative to the variation in western North Pacific anomalous cyclone(WNPC), which can in turn be attributed to the different sea surface temperature anomaly(SSTA) over the Tropical Pacific. The remote forcing of negative SSTA in the equatorial central and eastern Pacific and the local air-sea interaction in the western North Pacific are the usual causes of WNPC formation and maintenance.SSTA in the first spring is stronger than those in the second spring. As a result, the intensity of WNPC in the first year is stronger, which is more likely to reduce the moisture in southern China by changing the moisture transport, leading to prolonged precipitation deficits over southern China. However, the tropical SSTA signals in the second year are too weak to induce the formation and maintenance of WNPC and the below-normal precipitation over southern China. Thus, the variation in tropical SSTA signals between two consecutive springs during multiyear La Ni?a events leads to obvious differences in the spatial pattern of precipitation anomaly in southern China by causing the different WNPC response. 展开更多
关键词 multiyear La Nina precipitation anomaly anomalous western North Pacific cyclone southern China
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