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A new type of micro-disseminated gold deposits in association with diabase found in Yunnan and Guizhou provinces and Guangxi Zhuang Autonomous Region——Their geological characteristics and metallogenic conditions 被引量:2
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作者 LI Zhuyun LAN Tianlong +1 位作者 RAN Ruide CHENG Guofan 《Chinese Journal Of Geochemistry》 EI CAS 2012年第4期449-456,共8页
With the continuous development of gold ore prospecting and exploration in recent years a new type of micro-disseminated gold deposits have been found in the regions of Southwest Guizhou Province and Northwest Guangxi... With the continuous development of gold ore prospecting and exploration in recent years a new type of micro-disseminated gold deposits have been found in the regions of Southwest Guizhou Province and Northwest Guangxi Zhuang Autonomous Region,with the orebodies directly occurring in diabase or in the contact zone between diabase and strata.The orebodies are strictly controlled by fault structures.The discovery of this type of gold deposits has brought about new prospects for gold ore prospecting in the Yunnan-Guizhou-Guangxi Golden Triangle region.From the preliminary analysis of the geological characteristics of the Qiaoxiang gold deposit in Wangmo County,in combination with the results of research work in the adjacent areas in recent years,this paper roughly described the geological characteristics and metallogenic conditions of this type of gold ore deposits with an attempt to make more and more geologists pay enough attention to this type of gold ore deposits,so as to promote gold ore prospecting in Guizhou Province to develop toward a variety of types of gold deposits in all round way. 展开更多
关键词 微细浸染型金矿床 广西壮族自治区 成矿地质条件 地质特征 辉绿岩 贵州省 类型 云南
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Geochemical Tracing of Ore-forming Material Sources of Carlin-type Gold Deposits in the Yunnan-Guizhou-Guangxi Triangle Area --A Case Study of the Application of the Combined Silicon Isotopes Geochemistry and Siliceous Cathodoluminescence Analysis 被引量:1
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作者 LIU Xianfan NI Shijun +2 位作者 LU Qiuxia JIN Jingfu ZHU Laimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期30-39,共10页
Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Gui... Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Guizhou-Guangxi triangle area. The study shows that primary silicified quartz is nonluminescent but quartz in host rocks and secondary silicified quartz are luminescent by the action of cathode rays. Correspondingly, silicon isotope compositions of host rocks, ores and hydro6thermal quartz veins are clearly distinguished. In strata from the Middle Triassic to the “Dachang” host bed, δ30Si of the host rocks ranges from 0.0% ?0.3%, while that of primary ore-forming silicified fluids from ?0.1% to ?0.4%; in the Upper Permian and Lower Carboniferous strata and Indosinian diabase host beds, δ30Si of the host rocks is from ?0.1% to ?0.2% and that of the primary silicified quartz veins from 0.3 % ?0.5 %. This pattern demonstrates the following geochemical mineralization process, primary ore-forming siliceous fluids migrated upwards quickly along the main passages of deep-seated faults from mantle to crust and entered secondary faults where gold deposits were eventually formed as a result of permeation and replacement of the siliceous ore-forming fluids into different ore-bearing strata. This gives important evidence for the fact that ore-forming fluids of this type of gold deposits were mainly derived from upper mantle differentiation and shows good prospects for deep gold deposits and geochemical background for large and superlarge gold deposits. 展开更多
关键词 silicon isotope siliceous cathodoluminescence tracing of ore-forming material source Carlin-type gold deposit yunnan-guizhou-guangxi triangle area
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GEODYNAMICS OF SUPERLARGE DEPOSITS IN CHINSES YUNNAN-GUIZHOU-GUANGXI ON THE EASTERN MARGIN OF THE QINGZANG PLEAUTAN
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作者 Fang Weixuan, Hu Ruizhong, Su Wenchao 《地学前缘》 EI CAS CSCD 2000年第S1期413-415,共3页
Interest in the ore\|forming histories of basins has grown rapid since 1960 and is now intensive. The main reason behind the acceleration is the increasing awareness that the natural processes responsible for generati... Interest in the ore\|forming histories of basins has grown rapid since 1960 and is now intensive. The main reason behind the acceleration is the increasing awareness that the natural processes responsible for generating metal deposits in the sedimentary basin from the source rocks of the beneath the basin and intensively hydrothermal activity in the basin. Observations made in different continental margin basin systems and superlarge deposits in Chinese Yunnan\|Guizhou\|Guangxi Province on the eastern margin of the Qingzang (Himalaya—Karakoram—Tibet) were investigated in terms of geodynamics of basin formation. Geotectonically, the area is situated in the conjoint between the Tethys—Himalaya and the Marginal\|Pacific tectonic domain, characterized by very complex geological structure, typical basin\|mountain tectonics, abundant Superlarge deposits. 展开更多
关键词 SUPERLARGE deposits geodynamics EXTENSIONAL tectonics sedimentary basin mantle plume extension of LITHOSPHERE Chinese yunnan\|Gui zhou\|guangxi Province
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Indosinian Foreland Fold-and-Thrust Belt Bordering Yunnan and Guangxi, China 被引量:3
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作者 WU Genyao Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第4期391-397,共7页
Recent discoveries of ophiolites indicate that there must be a Palaeotethyan geosuture zone bordering China and Vietnam, which separates the Vietbac block from the South China subcontinent. The Indosinian foreland fol... Recent discoveries of ophiolites indicate that there must be a Palaeotethyan geosuture zone bordering China and Vietnam, which separates the Vietbac block from the South China subcontinent. The Indosinian foreland fold-and-thrust belt bordering Yunnan and Guangxi provided further evidence for the palaeotethysides. The oceanic crust was subducted southwestwards while the magmatic arc migrated northeastwards, and the continent-arc collision occurred in the Late Triassic with the thrusting being extended towards the north or northeast. The features of thrust-nappe structure are discussed, which proved the continental margin of the Palaeotethyan ocean there to be a complicated one. A face-to-face collision occurred first along the NW-striking segment and then along the ENE-striking segment accompanied by transpression or oblique thrusting occurring along the NW-striking one. 展开更多
关键词 thrust-nappe structure foreland fold-and-thrust belt palaeotethysides border between yunnan and guangxi
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Geochemical anomaly and the causes of transition metal accumulations in late Permian coal from the eastern Yunnan-western Guizhou region 被引量:2
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作者 Wu Yanyan Qin Yong +1 位作者 Wang Aikuan Shen Jian 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期105-111,共7页
The concentration of 39 trace elements in coal from the late Permian taken from the eastern Yunnan-western Guizhou region was determined using inductively coupled plasma mass spectrometry. It was found that the mean c... The concentration of 39 trace elements in coal from the late Permian taken from the eastern Yunnan-western Guizhou region was determined using inductively coupled plasma mass spectrometry. It was found that the mean content of Ti, V, Cr, Mo, Co, Ni, Y, and Zr is higher than the national average. The occurrence of Mn, Ni, and Co in the different coalfields is distinctly different. Most of the enriched transition metal elements exist mainly as inorganic minerals. In the Zhina coalfield, Co, Ni, and Nb are primarily associated with sulfur. Mn, Cs, and Mo are mostly sulfides. Almost all Co was organic and a significant part of the Ni is also organic in the Liupanshui coalfield. Cs, Co, and Ni are related to sulfur in the coal taken from eastern Yunnan. Carbonate is the main form of Mn in the coal from eastern Yunnan and the Liupanshui coalfield. Ti is the oxide in the coal samples where Ti is enriched. Zr is in the form of zircon in the samples where Zr is enriched. The situation for most of the transition metal elements is consistent with terrestrial genesis. Coal seams are universally influenced by the sea. The strongly seawater effected peat bog with a reductive and alkaline environment favors the relative enrichment of Mn. A reducing environment is conducive to transition metal element enrichment. 展开更多
关键词 East yunnan West guizhou Late Permian Transition metal elements in coal Geochemical
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Geological characterization and exploration potential of shale gas in the Carboniferous Jiusi Formation,northern Guizhou and Yunnan provinces,SW China
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作者 Weiming Feng Rong Li +3 位作者 Zhan Zhao Qian Yu Wei Liu Junfeng Cao 《Energy Geoscience》 2023年第3期169-181,共13页
Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential ... Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential of organic-rich shales in this area are yet to be quantified, thus limiting the prospect of shale gas in this area. This study investigates the basic geological conditions of Jiusi shale gas, using core data, well-logs, and some other test data, obtaining the following results. The organic-rich shales are mainly composed of deltaic-to-shallow-shelf deposits, with thickness ranging from 0 to 450 m, and above 350 m around the subsidence center. The organic matter is mainly type Ⅱ kerogen with TOC content of mostly 1%–2%, indicating a moderate maturity. The argillaceous shale reservoirs are indicative of strong heterogeneity, high clay minerals content, low porosity, low permeability, high specific surface area, and relatively developed secondary porosity. The gas-log anomaly intervals obtained from the survey wells have a cumulative thickness that is apparently greater than 200 m, and a few shale intervals showing high desorbed and adsorbed gas contents. Due to complex structures in the study area, conditions responsible for shale gas occurrence and trapping are generally moderate. However, areas having wide and gentle folds with moderate depth of burial reveals relatively favorable conditions of hydrocarbon traps. In contrast with typical marine-continental transitional shales, the Jiusi shale have better geological conditions for shale gas preservation. The analysis of the geological framework and hydrocarbon potential of Carboniferous Jiusi Formation provide more insight for the exploration of Carboniferous shale gas in southern China. 展开更多
关键词 Marine-continental tansitional fades 0rganic-nich shale Shale gas Exploration potential CARBONIFEROUS Northem border area between guizhou and yunnan China
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Triassic Transgressive-Regressive Sequences in Guizhou-Guangxi Region, South China 被引量:6
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作者 Wei Jiayong (Regional Geological Survey, Xi’an College of Geology, Xi ’an 710054) Liao Nengmao Yu Youyi (Regional Geological Surveying Institute of Guizhou, Guiyang 550005) 《Journal of Earth Science》 SCIE CAS CSCD 1996年第1期112-121,共10页
Seven third-order transgressive-regressive sequences are recognized in the Early Triassic -Early Carnian stratigraghc succession of Guizhou-Guangxi region, South China. Based on currently available ages by the correla... Seven third-order transgressive-regressive sequences are recognized in the Early Triassic -Early Carnian stratigraghc succession of Guizhou-Guangxi region, South China. Based on currently available ages by the correlation of conodont ammonites and bivalve faunas, these sequences range approximately from 1.0 Ma to 5.6 Ma, with the average of 3 Ma. They occur largely in the Griesbachian-Dienerian, Smithian,uppermost Smithian-lowermost Anisian, Lower Anisian, Middle Anisian, Upper Anisian-Upper Ladinian and the uppermost Ladinian-Lower Carnian respectively, and can be grouped into three second-order transgressive-regressive supersequences. A relative sea level curve is established from the sequence stratigraghic analysis. Transgressive-regressive sequences,bounded by transgressive surfaces and the correlatable unconformities, are real unconformity-bounded units of lower rank. Each sequence comprises transgressive, highstand and regressive systems tracts, and can be easily correlated with the depositional sequence. 展开更多
关键词 TRIASSIC transgressive-regressive sequence relative sea level change guizhou guangxi.
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Geochemical Indication of Sinian Bedded Siliceous Rocks in the Hunan-Guizhou-Guangxi Area and Their Environmental Significance 被引量:3
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作者 PENG Jim YI Haisheng XIA Wenjie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第1期46-53,共8页
: In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. The... : In the Hunan-Guizhou-Guangxi area there have developed very thick bedded siliceous rocks of the late Sinian. The rocks have a fairly pure composition, with an average content of siliceous minerals exceeding 95%. They are relatively rich in Fe and Mn, and poor in Al, Ti and Mg. The Fe/Ti, (Fe+Mn)/Ti, Al/(Al+Fe+Mn) and U/Th ratios and the Al-Fe-Mn and Fe-Mn-(Ni+Co+Cu)×10 triangle diagrams all show that they are hydrothermal sedimentary siliceous rocks. In the rocks the total amount of REEs is low, the δCe shows an obvious negative anomaly and the δEu a weak anomaly, and LREE>HREE, all indicating that they are products of hydrothermal processes. The δ30Si and δ18O values, as well as the formation temperature of the rocks all clearly show that the silica forming the rocks comes from hot water. Besides, analyses of the depositional environment of the rocks using the MnO/TiO2 ratio and the δCe and δ30Si values yield the same conclusion that they are formed in environments from continental marginal slopes of a bathyal environment to oceanic basins of a deep-sea environment. 展开更多
关键词 siliceous rock hydrothermal sedimentary geochemistry environment SINIAN the Hunan-guizhou-guangxi area
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Facies-succession and architecture of the third-order sequences and their stratigraphic framework of the Devonian in Yunnan-Guizhou-Guangxi area,South China 被引量:7
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作者 Mei Mingxiang Maurice E.Tucker 《Journal of Palaeogeography》 SCIE 2013年第1期93-108,共16页
The Caledonian orogeny at the end of the Silurian resulted in great changes in the palaeogeography in the Yunnan-Guizhou-Guangxi area of South China; the continental area of the Early Paleozoic evolved into the extens... The Caledonian orogeny at the end of the Silurian resulted in great changes in the palaeogeography in the Yunnan-Guizhou-Guangxi area of South China; the continental area of the Early Paleozoic evolved into the extensive Dian-Qian-Gui Sea in the Late Paleo-zoic. Early in the Devonian, as a result of a major transgression, seawater encroached gradually from the south to the north and clastic facies were deposited. Carbonate deposition was then established in the Yunnan-Guizhou-Guangxi area, with a palaeogeography marked by attached platforms, isolated platforms and narrow basins. As a result of the Ziyun movement towards the end of the Devonian, the Upper Devonian strata are regressive and thin out from the open-sea to the land areas. A study of the nature and distribution of sedimentary facies in space and time recognises 13 third-order sequences in the Devonian strata in Yunnan-Guizhou-Guangxi area, and these form two second-order sequences. The strata of the Lower Devonian comprise 5 third-order sequences (SQ1 to SQ5 ), which are dominated by transgressive clastics. 4 third-order sequences (SQ6 to SQ9 ) in the Middle Devonian are characterized by alternations of transgressive clastics and highstand carbonates. In the Upper Devonian, carbonates constitute 4 third-order sequences (SQ10 to SQ13 ), which are generally marked by the transgressive limestones and highstand dolomites. On the basis of earlier biostratigraphic studies, sea-level changes represented by the third-order sequences with their different facies successions are explored, and the sequence stratigraphic framework is established. There-fore, the Devonian strata in the study area provide an example for further understanding of depositional trends within the sequence-stratigraphic framework. 展开更多
关键词 sequence stratigraphy DEVONIAN yunnan-guizhou-guangxi area South China
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A sulfur isotope study of fine disseminated gold deposits in the Yunnan-Guizhou-Guangxi triangle area 被引量:1
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作者 LU jianjun, ZHAI Jianping, CHEN Xiaoming and GAO Jianfeng State Key Laboratory of Mineral Deposit Research, Nanjing University, Nanjing 210093, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第S2期180-182,共3页
THE fine disseminated gold deposits in Yunnan-Guizhou-Guangxi triangle area in S. China occur in thesedimentary rocks and are not relative to magmatism in space and genesis. Many authors have studiedthese deposits and... THE fine disseminated gold deposits in Yunnan-Guizhou-Guangxi triangle area in S. China occur in thesedimentary rocks and are not relative to magmatism in space and genesis. Many authors have studiedthese deposits and obtained different conclusions. This note makes the first systematic study on sulfur isotope compositions to further discuss possible sources of ore-forming materials. 1 Sulfur isotope composition Figure 1 shows variations of sulfur isotope compositions of 232 sulfide separats from various depositsand their host rocks. S S values of pyrite from Mid-Triassic Banna Formation strata in the Jinya ore district can be divided into two groups: -7.4‰ to -6.4‰ and 2.7‰ to 14.1‰. Pyrite from the Jinyadeposits has δ<sup>34</sup>S values of -7.2‰-1.9‰, stibnite -6.7‰- -4.9‰ and arsenopyrite -4.1‰- 展开更多
关键词 sulfur isotope FINE DISSEMINATED gold deposits yunnan guizhou guangxi.
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Trends in sunshine duration and atmospheric visibility in the Yunnan-Guizhou Plateau,1961-2005 被引量:4
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作者 XiaoBo Zheng TianLiang Zhao +2 位作者 YuXiang Luo ChangChun Duan Juan Chen 《Research in Cold and Arid Regions》 2011年第2期179-184,共6页
Using the observed data from 184 stations over the Yunnan-Guizhou Plateau (YGP) from 1961 to 2005, the long-term trends in sunshine duration, cloud amount, dry visibility (Vd), dry extinction, and water vapor over... Using the observed data from 184 stations over the Yunnan-Guizhou Plateau (YGP) from 1961 to 2005, the long-term trends in sunshine duration, cloud amount, dry visibility (Vd), dry extinction, and water vapor over the YGP are analyzed. The results show that 85% of the stations recorded shortening annual sunshine duration, with the decrease rates between -12.2 and -173.7 h/10yr. Results of Mann-Kendall tests indicate that, among the stations with decreasing sunshine duration, 63.7% of them experienced an abrupt change that started in the 1970s and peaked in the 1980s. This decreasing trend has reversed in the early years of the 21st century. The cloud cover and water vapor content in the mid and lower levels over the YGP had no obvious changes during the study period. The annual averages of Vd declined from 34 km in the 1960s to 27 km at present. The annual mean dry extinction coefficient trended upward, from 0.176 to 0.190, on the YGP from 1980 to 2005. Analyses of cloud cover, water vapor, atmospheric visibility, and dry extinction coefficient revealed that emitted tropospheric aerosols (including air pollutants) resulting from increased energy consumption over the YGP could be a major Factor influencing the reductions of sunshine duration and atmospheric visibility. 展开更多
关键词 yunnan-guizhou Plateau climatic change sunshine duration VISIBILITY cloudy cover
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Characteristics of microbial communities in water from CBM wells and biogas production potential in eastern Yunnan and western Guizhou, China
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作者 Wenguang TIAN Zhaobiao YANG +4 位作者 Zonghao QIN Yong QIN Cunlei LI Benju LU Yongchen LI 《Frontiers of Earth Science》 SCIE CSCD 2023年第1期180-196,共17页
The study of microbial communities in the produced water of coalbed methane(CBM)wells is an important aspect of microbial-enhanced methane production.Water produced from 15 CBM wells in four synclines in eastern Yunna... The study of microbial communities in the produced water of coalbed methane(CBM)wells is an important aspect of microbial-enhanced methane production.Water produced from 15 CBM wells in four synclines in eastern Yunnan and western Guizhou was collected.Through the use of 16S ribosomal RNA(16S rRNA)amplicon sequencing and realtime fluorescence quantitative polymerase chain reaction(PCR),the characteristics of bacterial and archaeal communities before and after enrichment culture were studied.The methanogenic pathways of secondary biogas were discussed,and potential microbial-enhanced methane production was preliminarily evaluated.The results showed that the bacterial DNA content in uncultured produced water was low,so it is difficult to detect.After enrichment,the dominant bacteria phyla were Proteobacteria,Bacteroidetes,and Firmicutes.A total of seven phyla were detected in the uncultured produced water,and the dominant archaeal phylum was Euyarchaeota.Methanogens were the main component of archaea.The dominant archaeal genera were Methanobacterium,Methanoculleus and Methanobrevibacter.The community structure of the archaea changed noticeably after four days of enrichment culture.The relative abundance of Euryarchaeota increased to 99%in most samples after enrichment culture.It was found that there was a transition from Methanoregula to Methanobacterium within genera.The relative abundance of Methanobacterium increased,which can produce hydrogenotrophic methane.Combined with the isotopic composition of the produced water and gas,it is considered that the CBM in the Tucheng and Enhong synlines consists of a mixture of thermogenic gas and biogas.The proportion of secondary biogas in the Tucheng and Enhong synlines are estimated to range from 10.89% to 49.62%.There are mainly hydrogentrophic methanogens in the study area,and CO_(2) reduction is the main way of microbial gas production.After enrichment culture of produced water in the study area,the hydrogenotrophic methanogens were enriched.These two areas have strong potential for microbial-enhanced methane production. 展开更多
关键词 eastern yunnan and western guizhou produced water form CBM wells 16S amplicon sequencing secondary biogas microbial-enhanced methane production
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Prehistoric agriculture development in the Yunnan-Guizhou Plateau, southwest China: Archaeobotanical evidence 被引量:7
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作者 LI HaiMing ZUO XinXin +7 位作者 KANG LiHong REN LeLe LIU FengWen LIU HongGao ZHANG NaiMeng MIN Rui LIU Xu DONG GuangHui 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第8期1562-1573,共12页
The origin, development and expansion of prehistoric agriculture in East Asia have been widely investigated over the past two decades using archaeobotanical analysis from excavated Neolithic and Bronze Age sites. Rese... The origin, development and expansion of prehistoric agriculture in East Asia have been widely investigated over the past two decades using archaeobotanical analysis from excavated Neolithic and Bronze Age sites. Research on prehistoric agriculture has predominantly focused in the valleys of the Yellow River and the Yangtze River. Agricultural development during the Neolithic and Bronze Age periods in the Yunnan-Guizhou Plateau of southwest China, an important passageway for human migration into Southeast Asia, still remains unclear. In this paper, based on macrofossil and microfossil analysis and radiocarbon dating at the Shilinggang site, we investigate plant subsistence strategies in the Nujiang River valley during the Bronze Age period. Combined with previous archaeobotanical studies in the Yunnan-Guizhou Plateau, we explore agricultural development processes in this area during the Neolithic and Bronze Age. Our results indicate that rice and foxtail millet were cultivated in Shilinggang around 2500 cal a BP. Three phases of prehistoric agricultural development in the Yunnan-Guizhou Plateau can be identified: rice cultivation from 4800–3900 cal a BP, mixed rice and millet crop(foxtail millet and broomcorn millet) cultivation from 3900–3400 cal a BP, and mixed rice, millet crop and wheat cultivation from 3400–2300 cal a BP. The development of agriculture in the Yunnan-Guizhou Plateau during the Neolithic and Bronze Age periods was primarily promoted by prehistoric agriculture expansion across Eurasia, agricultural expansion which was also affected by the topographic and hydrological characteristics of the area. 展开更多
关键词 Nujiang River valley yunnan-guizhou Plateau NEOLITHIC Bronze Age Macrofossil analysis Phytolith analysis Radiocarbon dating
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^(40)Ar/^(39)Ar dating of cryptomelane from the Baye manganese deposit,SW Yunnan,China:Implications for growth rate of supergene Mn-oxide veins
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作者 DENG XiaoDong LI JianWei 《Science China Earth Sciences》 SCIE EI CAS 2013年第10期1654-1663,共10页
Supergene Mn-oxide deposits are commonly related to thick weathering profiles and form as a result of intense and prolonged weathering of Mn-bearing precursor rocks, processes facilitated by a combination of multiple ... Supergene Mn-oxide deposits are commonly related to thick weathering profiles and form as a result of intense and prolonged weathering of Mn-bearing precursor rocks, processes facilitated by a combination of multiple factors including warm and wet climate, relatively quiescent tectonic environment, and favorable geomorphic setting. Precise age constraints of supergene Mn-oxides may provide valuable information on the climatic, tectonic, and geomorphic conditions prevailing in the geological past. 4~Ar]39Ar laser incremental heating analysis of cryptomelane from the Baye manganese deposit, western Yunnan-Guizhou Plateau, SW China, was conducted to provide numerical constraints on the ages of supergene Mn enrichment and growth rates of Mn-oxide veins. In this study, two Mn-oxide veins of 3-6 cm thickness, termed as Vein A and B, respectively, were col- lected for 4~Ar/39Ar dating. Vein A is subhorizontal and present in fractures parallel to schistosity of the Proterozoic spessartine schists, whereas Vein B is filled in nearly vertical fractures penetrating the schistosity. A combination of optical microscopy, XRD, SEM, and EMP analyses demonstrate that mineral grains extracted from both veins consist of pure, well-crystallized cryptomlane, which has acicular crystal forms and contains 0.96%4.70% K2O. Fourteen cryptomelane subsamples extracted from different growth bands of Vein A yield well-defined plateau ages ranging from 1.35 ± 0.05 to 1.16 ± 0.04 Ma (2or), whereas seven subsamples obtained from Vein B have plateau ages ranging from 1.23 ±0.05 to 1.01 ± 0.04 Ma (20). The age results permit estimation for the growth rates of both veins at ca. 115-153 and 34-67 mm Ma-1, respectively. Distinct growth rates between Veins A and B are likely reflective of different fluid pressures during their formation governed by the orientation of the fractures hosting the veins. The growth rates calculated for both veins are 1-2 orders of magnitude higher than the val- ues (〈1-10 mm Ma-l) estimated for Mn-oxide nodules in supergene Mn deposits elsewhere. The high growth rates obtained for the Baye samples are consistent with direct precipitation of tetravalent Mn-oxides from weathering solution in open cavities or fractures, characterized by incremental growth of Mn-oxide bands from the margin to the center of the cavities or fractures. In contrast, Mn-oxide nodules with low growth rates from other deposits formed through self-oxidation and self-catalization, and grow outwards from the nuclei. In addition, prevalence of warm and humid climate and prolonged tectonic uplift in the Yunnan Plateau may have also partly contributed to the rapid growth of Mn-oxides in the Baye deposit. 展开更多
关键词 CRYPTOMELANE 40Ar/39Ar dating growth rates growth mechanism yunnan.guizhou Plateau
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黔北—滇东二叠纪锰矿主要成矿规律与成矿区带划分 被引量:1
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作者 刘志臣 周琦 +3 位作者 杨瑞东 杜远生 陈登 肖林 《矿产综合利用》 CAS 2024年第1期62-72,共11页
这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期... 这是一篇地球科学领域的论文。锰矿为我国十分紧缺的战略矿产之一。黔北-滇东地区是我国二叠纪锰矿最典型的分布区,在全球晚古生代也较为少见,该区锰矿资源丰富,找矿潜力巨大,称为“遵义式锰矿”。研究表明,该区锰矿产于二叠纪茅口晚期,分布严格受黔北裂谷盆地控制,锰矿在地堑盆地中心喷溢沉积成矿,在地垒区则无锰矿分布,矿体空间展布方向与盆地展布方向基本一致。其中,黔北遵义-黔西地区锰矿在空间上分布于盆地相区,并可分为中心相、过渡相、边缘相等三个锰矿相带,进一步指示了锰矿具体成矿位置,显示了锰矿受盆地中心控制非常明显的特点。在划分的遵义-宣威锰矿成矿带的基础上,详细划分出遵义-黔西锰矿成矿亚带中深溪—八里、龙坪—兴隆、团溪—尚稽、黔西4个锰矿矿集区,以及水城-宣威锰矿成矿亚带中水城—纳雍、格学2个锰矿矿集区。该研究成果对寻找黔北—滇东二叠纪隐伏锰矿床,开展成矿预测,具有重要的意义。 展开更多
关键词 地球科学 二叠纪锰矿 成矿规律 成矿区带 黔北—滇东
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云贵川非物质文化遗产与传统村落空间分布格局及影响因素 被引量:3
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作者 张晓瑞 顾天飞 卫辉 《资源开发与市场》 CAS 2024年第1期33-41,共9页
基于核密度、空间重心模型、空间错位指数和地理探测器等方法,系统分析了云贵川非物质文化遗产(非遗)和传统村落的空间分布格局,包括空间分布密度和空间错位的程度、强度与类型,并探讨了影响其空间分布的因素。结果显示:①非遗和传统村... 基于核密度、空间重心模型、空间错位指数和地理探测器等方法,系统分析了云贵川非物质文化遗产(非遗)和传统村落的空间分布格局,包括空间分布密度和空间错位的程度、强度与类型,并探讨了影响其空间分布的因素。结果显示:①非遗和传统村落的空间分布结构分别为“两核一带多点”和“北疏、南密、中空”;②两者的总体空间错位特征明显,各州市在空间错位的程度、强度和类型上均具有差异性;③非遗和传统村落的空间分布都受到地形地貌和河流水系等自然环境因素的影响,在社会经济影响因素上,非遗空间分布的主要影响因素是文化和经济发展,传统村落空间分布的主要影响因素是人口和文化。 展开更多
关键词 非物质文化遗产 传统村落 空间错位 影响因素 云贵川
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1875年广西与贵州之间强震与地震密集关系分析
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作者 王健 和泰名 +1 位作者 周贝贝 林国良 《地震研究》 CSCD 北大核心 2024年第4期588-595,共8页
1875年在广西与贵州之间发生了一次强烈地震,《中国历史强震目录(公元前23世纪—公元1911年)》和《中国历史地震图集》所给出的震中位置差异较大。针对相关史料进行梳理,通过计算研究区的中小地震密集区之后发现,广西乐业和贵州望谟分... 1875年在广西与贵州之间发生了一次强烈地震,《中国历史强震目录(公元前23世纪—公元1911年)》和《中国历史地震图集》所给出的震中位置差异较大。针对相关史料进行梳理,通过计算研究区的中小地震密集区之后发现,广西乐业和贵州望谟分别存在地震密集区与上述两个震中对应。依据地震密集与历史强震的关系,分析了上述两种震中位置的合理性和可能结果,认为广西乐业和贵州望谟存在着两次6级左右的强震的可能性。 展开更多
关键词 历史地震 地震烈度 地震活动性 地震危险性 广西 贵州
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桂滇黔民族地区乡村旅游促进留守妇女可持续生计演进与影响因素研究
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作者 唐凡茗 李淑贤 李照红 《旅游论坛》 2024年第8期43-51,共9页
随着桂滇黔民族地区乡村旅游的蓬勃发展,受其影响,当地留守妇女重构了该地区土地资源、劳动供给、劳动技能技术和资本等生产要素配置,进而促进了桂滇黔民族地区留守妇女生计的转型。文章通过分析桂滇黔民族地区旅游发展的不同阶段特点,... 随着桂滇黔民族地区乡村旅游的蓬勃发展,受其影响,当地留守妇女重构了该地区土地资源、劳动供给、劳动技能技术和资本等生产要素配置,进而促进了桂滇黔民族地区留守妇女生计的转型。文章通过分析桂滇黔民族地区旅游发展的不同阶段特点,剖析了该地区留守妇女生计演进的过程,可划分为农业主导型生计模式、混合兼业型生计模式和旅游主导型生计模式等3个阶段。结合旅游可持续生计分析研究框架,桂滇黔民族地区留守妇女可持续生计由外在因素和内在因素共同作用。桂滇黔民族地区留守妇女获得经济收入、提升技能和增强社会参与度,有助于文化传承和家庭关系的改善,提升了桂滇黔民族地区留守妇女可持续生计潜力。梳理桂滇黔民族地区乡村旅游对留守妇女生计演变过程与影响因素,不仅有助于深化对生计转型机制的理解、丰富乡村经济与社会发展理论和促进性别与发展研究的深化,还能为政策制定提供理论借鉴和参考。 展开更多
关键词 桂滇黔民族地区 乡村旅游 留守妇女 可持续生计 影响因素
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我国西南茶叶主产省茶产业发展现状与竞争力比较分析
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作者 伏成秀 张文云 +2 位作者 张庆 钱敏 董晓波 《中国食物与营养》 2024年第4期21-26,共6页
目的:西南地区是我国茶产业重要地区,茶产业也是西南地区重要的农业产业,对云南、贵州和四川3个茶叶主产省展开竞争力评价及分析制约因素对产业高质量发展具有重要意义。方法:从茶叶生产、产业结构、经济效益、出口贸易等方面梳理3省茶... 目的:西南地区是我国茶产业重要地区,茶产业也是西南地区重要的农业产业,对云南、贵州和四川3个茶叶主产省展开竞争力评价及分析制约因素对产业高质量发展具有重要意义。方法:从茶叶生产、产业结构、经济效益、出口贸易等方面梳理3省茶产业发展现状,运用资源禀赋系数、显示性比较优势指数和综合比较优势指数评价云贵川3省茶产业竞争力。结果:云贵川3省具有拥有较强的资源禀赋、产业规模优势及综合比较优势,云南、贵州具有较强的出口贸易竞争力,但均存在相对出口不足的问题,贵州、四川生产效率比较优势不足。结论:结合云贵川3省茶产业发展及竞争力定量分析,从持续加强茶产业的扶持发展、提升茶叶国际贸易竞争力、推动茶产业高质量发展等方面给予对策建议。 展开更多
关键词 云贵川 茶产业 发展现状 竞争力
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明清以来川滇黔地区饮食文化变迁中民族交往交流交融及其特点
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作者 杜莉 王胜鹏 《民族学刊》 CSSCI 北大核心 2024年第5期48-56,124,共10页
各民族交往交流交融是民族关系和谐发展的重要保证,更是新时代铸牢中华民族共同体意识、建设中华民族共同体的重要路径。饮食文化是中华优秀传统文化的重要组成部分,凝结了大量民族交往交流交融的实践内容和价值意蕴。川滇黔地区是我国... 各民族交往交流交融是民族关系和谐发展的重要保证,更是新时代铸牢中华民族共同体意识、建设中华民族共同体的重要路径。饮食文化是中华优秀传统文化的重要组成部分,凝结了大量民族交往交流交融的实践内容和价值意蕴。川滇黔地区是我国最具代表性的民族聚居区和饮食文化遗产富集区。明清以来直至当今,该地区汉族和各民族在食材运用、饮食品及其制作技艺、饮食习俗等饮食文化的多个方面进行着交流与交融,并且其途径、方式、结果和作用等方面呈现出三个显著特点,即川滇黔地区民族饮食文化交流交融的途径主要是人口迁移流动和商贸往来,其方式主要是双向交流、相互影响,其结果和作用是促进了川滇黔地区各民族饮食文化的多元与共性并存、推动了区域饮食风味的共同体川菜、滇菜、黔菜的定型与繁荣发展,进而助推了多元一体的中国饮食文化和中国菜系的丰富与兴盛,从饮食文化的角度为铸牢中华民族共同体意识、推进中华民族共同体建设作出了独特贡献。 展开更多
关键词 明清以来 川滇黔地区 民族交往交流交融 饮食文化
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