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CHECK AND CORRECTION OF PRINCIPAL REFRACTIVE INDEX MEASUREMENTS OF ANISOTROPIC MINERALS

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Science China Chemistry 1987年第10期30卷 1101-1108页

作者：刘智星 Kunming yunnan institute of geology

From a thorough study of the indicatrixes of anisotropic minerals, the author derives the equation of the basic error of principal refractive index measurements of anisotropic minerals, interprets completely the resolution of the equation, and puts forward a method to check and correct the measurements. This method can be used to identify the dependability of the measurements, study the subtle changes of them, and resolve the contradiction existing for a long time between the measured optic angle of a biaxial crystal and the optic angle calculated according to the principal refractive index measurements.

关键词： CHECK AND CORRECTION OF PRINCIPAL REFRACTIVE INDEX MEASUREMENTS OF ANISOTROPIC MINERALS

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi Shi Willie Soon ShiCan Qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

Guazia, the earliest ovule without cupule but with unique integumentary lobes

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National Science Review 2022年第4期9卷 13-20页

作者： De-Ming Wang Le Liu Yi Zhou Min Qin Mei-Cen Meng Yun Guo Jin-Zhuang Xue Key Laboratory of Orogenic Belts and Crustal Evolution Department of GeologyPeking University School of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing) institute of geology and Paleontology Linyi University institute of Deep Time Terrestrial Ecology Institute of PalaeontologyYunnan Key Laboratory of Earth System ScienceYunnan University

The earliest ovules in the Late Devonian(Famennian) are surrounded by a cupule that is involved in both protection and pollination, and generally have free integumentary lobes. Here we report a new taxon from the Famennian of China, Guazia dongzhiensis gen. et sp. nov. The terminally borne ovule is apparently acupulate(without cupule) and has four radially arranged wing-like integumentary lobes that are extensively fused, and folded lengthwise and inwards. Guazia provides evidence that not all Devonian seeds possess a cupule and it increases their diversity in integumentary lobes. This genus also suggests that the integuments develop new functions, probably including wind dispersal at the expense of the cupules.

关键词： ovule cupule integument Devonian seed plants

Classification and Type Association of Tin Deposits in Southeast yunnan Tin Belt

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Chinese Journal Of Geochemistry 1991年第1期10卷 21-36页

作者：杨世瑜 Department of geology Kunming Institute of TechnologyKunmingYunnan

Pneumato-hypothermal to meso-epithermal tin-polymetallic(W, Be,Bi,Mo,Cu,Pb,Zn and Ag) deposits ,dominated by cassiterite-sulfide type and cassiterite-quartz type,are extensively developed around granite intrusives in the Southeast yunnan Tin Belt genetically related to Yenshanian *** deposits are grouped into two classes,four associations and fourteen type according to the classification scheme proposed by the author to reflect their geological and genetic characteristics as well as economic *** deposits are arranged in an appar-ent zonal pattern from the granite body outwards in terms of 'association'(cassiterite-feldspar→cassiterite-quartz→cassiterite sulfide),typical ore-forming metals(Sn-W-Be-Mo-Nb-Ta-Tr→Sn-W-Cu-In→Sn-Pb-Zn-As-Cd),and formation conditions(pneumato-hypothermal→hypothermal-mesothermal→mesothermal-epithermal),although such distribution pattern may be more or less complicated by local specialities of granit4 petrochemistry,host rock lithology and structure.

关键词：锡矿床云南花岗岩岩石化学成矿作用

Geochemical Characteristics of Gases From Hot Springs in Seismic Region

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Science China Chemistry 1994年第2期37卷 242-249页

作者：王先彬陈践发徐胜杨辉薛啸峰王文懿 State Key Lab of Gas Geochemistry Lanzhou Institute of Geology Academia Sinica Lanzhou 730000 PRC) yunnan institute of Geoscience Ministry of Geology and Mineral Resources Kunming 650011 PRC)

Chemical and isotopic compositions of He, Ar, CH4(δ13C) of hot spring gas in Lancang and Batang earthquake regions show that the concentrations of He , H2 , non-atmospheric sourced N2 and 3He/4He value are closely related to seismic activity. During earthquake activity, gas release is related to the dilation that rocks take on under stress action. Earthquake magnitude (energy) between the two seismic regions suggests that the amount of released gas from rocks increases significantly with the increase of magnitude and energy. As indicators of earthquake prediction, the following parameters of gases from hot spring are effective: He, 3He/4He, H2 and N2B/N2total.

关键词： compositions of hot spring gas helium and argon isotopes earthquake effect.

Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期 74-93页

作者： Ye YANG Steven A.BINNIE Sheng XU Cong-Qiang LIU Tibor J.DUNAI institute of Surface-Earth System Science School of Earth System Science Tianjin University institute of geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

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Geochemical characteristics of island-arc volcanic rocks in the Nan-Nam Pat-Phetchabun zone,northern Thailand

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Chinese Journal Of Geochemistry 2010年第4期29卷 337-342页

作者： SHEN Shangyue FENG Qinglai YANG Wenqiang ZHANG Zhibin Chongpom Chonglakmani State Key Laboratory of GPMR China University of Geology Hubei Wuhan 430074 China institute of Regional geology Yunnan Bureau of Geology and Mineral Resources Yunnan Yuxi 653110 China School ofGeotechnology Suranaree University of Technology Thailand

Late Permian-Early Triassic(P2-T1) volcanic rocks distributed on the eastern side of ocean-ridge and oceanic-island basalts in the Nan-Uttaradit zone were analyzed from aspects of petrographic characteristics,rock assemblage,REE,trace elements,geotectonic setting,etc.,indicating that those volcanic rocks possess the characteristic features of island-arc volcanic *** volcanic rock assemblage is basalt-basaltic *** volcanic rocks are sub-alkaline,dominated by calc-alkaline series,with tholeiite series coming *** chemical composition of the volcanic rocks is characterized by low TiO2 and K2O and high Al2O3 and *** REE patterns are of the flat,weak LREE-enrichment right-inclined *** trace elements are characterized by the enrichment of large cation elements such as K,Rb and Ba,common enrichment of U and Th,and depletion of Nb,Ta,Zr and *** petrochemical plot falls within the field of volcanic rocks,in consistency with the plot of island-arc volcanic rocks in the Jinsha River zone of *** island-arc volcanic zone,together with the ocean-ridge/oceanic island type volcanic rocks in the Nan-Uttaradit zone,constitutes the ocean-ridge volcanic rock-island-arc magmatic rock zones which are distributed in pairs,indicating that the oceanic crust of the Nan-Uttaradit zone once was of eastward *** work is of great significance in exploring the evolution of paleo-Tethys in the Nan-Uttaradit zone.

关键词：岛弧火山岩地球化学特征 Al2O3含量岩石学特征洋岛玄武岩玄武安山岩钙碱性系列泰国

MAGNETOSTRATIGRAPHY OF PRECAMBRIANCAMBRIAN BOUNDARY AT MEISHUCUN SECTION, yunnan PROVINCE

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Science China Chemistry 1990年第1期33卷 79-86页

作者：刘椿梁其中李燕平 institute of geology Academia Sinica Beijing 100011 PRC yunnan institute of geology Kunming 650011 PRC Department of Geophysical Stanford University Stanford California USA

Magnetostratigraphic studies of 112 cores specimens (249 samples) in a Precambrian-Cambrian section at Meishucun, Jinning County, yunnan Province reveal the following: (ⅰ) Around the Sinian-Cambrian boundary in the Meishucun section existed a mixed polarity zone in which the Meishucun fauna went through an evolution of appearance—flourish—extinction. (ⅱ) The Meishucun section had a paleolatitude of no more than 20° during the Sinian-Cambrian, The phosphate deposits in this region and in the Zhongyicun Member were formed in the low-latitude environments.

关键词： Sinian-Cambrian boundary magnetostratigraphy mixed polarity zone.

Late Quaternary Large Earthquakes on the Western Branch of the Xiaojiang Fault and Their Tectonic Implications

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Acta Geologica Sinica(English Edition) 2015年第5期89卷 1516-1530页

作者： LI Xi RAN Yongkang CHEN Lichun WU Fuyao MA Xinquan CAO Jun Key Laboratory of Active Tectonics and Volcano Institute of Geology China Earthquake Administration Earthquake Administration of yunnan Province

The Xiaojiang fault is a major active left-lateral fault along the southeastern margin of the Tibetan *** largest historical earthquake in yunnan Province, with a magnitude 8 and a mean coseismic left-lateral displacement of ~ 6.9 m, occurred on the western branch of the Xiaojiang *** this fault is important in understanding current deformation and kinematic characteristics of the Tibetan *** and stretches have been well undertaken on the Xiaojiang fault, while paleoseismic research work is always the weak link on this *** investigate the paleoseismic history and large earthquake activity of the Xiaojiang fault, we opened a large trench at the northern edge of Caohaizi sag pond on the western branch of the Xiaojiang *** paleoseismic events have been identified, and named E1 through E6 from the oldest to the *** and woods are abundant, 20 samples were dated to constrain the ages of the paleoseismic events at 40 000–36 300 BC, 35 400–24 800 BC, 9 500 BC–AD 500, AD 390–720, AD 1120–1620 and AD 1750–*** associate the youngest event E6 with the 1833 M8 *** E4, E5 and E6 show a continuous record of the western strand of the Xiaojiang fault in the late Holocene, with a average recurrence interval of 370–480 *** earthquake recurrence in the late Holocene is far less than the recurrence of 2000–4000 yr posed in previous ***, the seismic hazard on the Xiaojiang fault should be ***, the irregular recurrence of large earthquakes on the Xiaojiang fault and other faults in the Xianshuihe-Xiaojiang system, indicates the uneven southeastward extrusion of the Sichuan-yunnan block along the southeastern margin of the Tibetan Plateau.

关键词： Xiaojiang fault sag pond large trench paleoearthquake recurrence interval Sichuan-yunnan block