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1.
1.IntroductionForelandbasin,thesedimentarybasinlyingbetweenthefrontofanorogenandtheadjacentcraton,isanimportantaspectforthestudyonlithospheretectonicevolutionoforogen(e.g.,Tankard,1986,Ren,etal.,1991;Li,1992,Chen,etal.,1992,Liu,etal.,1994,LihouandAlien,1996,Li,etal.,1997,DongandZhang,1997).Currently,itisdividedintotwogenetictoes,i.e.,peripheralforelandbasinsituatedagainsttheouterarcoftheorogenduringcontinent-continentcollisionandretro-arcforelandbasinbehindamagmaticarclinkedwithsubductiono…  相似文献   

2.
彭琪瑞 《地质论评》1958,18(5):351-359
一.热液硫化矿床的一些分散元素热液矿床包括多数最重要的金属矿床,如Cu,Pb,Zn,Ag,Sb,Hg,Mo,W,U,Au等。除最后三种元素外,其余都以硫化物为主要存在方式。这些硫化矿物,除含上列元素外,还常常含有一些稀少的元素,如Cd,Ga,In,Tl,Gl,Re,Se,Te等,后者的含量和硫化物中  相似文献   

3.
Six Chinese ordinary chondrites (four of them have fallen in recent years and the trace element abundances have not yet been reported for the other two) were examined.The contents of 21 elements (Na,Cr,Mn,Sc,Se,Zn,Br,Ni,Fe,Co,Ir,Cu,Ga,As,Au,Sb,Os,W,Re,Pt,and Ru)in the magnetic fractions and 20 elements (Na,K,Ca,Sc,Cr,Mn,Fe,Co,Ni,Zn,Se,Br,La,Sm,Eu,Yb,Lu,Ir,Au,and As) in the non-magnetic fractions were de-termined by INAA. The results indicate that the 5 H-group chondrites show almost no difference in composition,but they are different from the Zhaodong L-group chondrite in elemental abundance.As a normalized element(relative to CI),the concentrations of Ga in the magnetic fractions can be used to classify ordinary chondrites(H-,L- and LL-group).The bulk composition and modal weight of each component calculated from element concentrations in different phases are in good agreement with the bulk rock analyses presented in the literature.  相似文献   

4.
1.IntroductionBythepracticeofoilfielddevelOPment,itisgraduallyrecognizedthatmicroscopicheterogeneityismportanttOthefluidflowandporethroatheterogeneityisthemostboortantthings,becauseitaffectSthedisplacementefficiency.TherearemanymethodstostudyporestrUctUresuchasthinsectionmethod,capillarypressurecurveanalysis,imagealanalysis,fluorescencemicroscopeandsoon(LuoZhitan,1986;CatZhong,1993,QiuYinan,1996;PenShied,1998).Fromcapillarypressurecurve,wecangetsomeparametersaboutthroatandvolumeofporeinp…  相似文献   

5.
TheNcoproterosoiciswelldevelopedinHUnjiangarea,JinnProvince,andarecomposedoftheMadaling,Baffongh,DiaoyUtaiformationsoftheQingbaikouSyStemandtheNanfen,Qiaotou,Waulong,BadaojiangandQinggoUZifonnationsoftheSilvanSyStem.In1992,aresearchofsequencestratigraphywasdonethereforthefirsttime(GaoandQiao,1992).Since1993,duringthemappingofif50on,outcropsequenCestratigl'aphyhasfatherstudiedtherebrig.l).~ENCE~NDARYTheconceptofdepositionalsequencelicitedbyupperandloadunconfondtywaspointedoutbySlo…  相似文献   

6.
1.Papers should be devoted mainly to various aspects of research concerning geosciences and related disciplines in China,such as stratigraphy,paleontology,origin and history of the Earth,structural geology,tectonics,mineralogy,petrology,geochemistry, geophysics,geology of mineral deposits,hydrogeology,engineering geology,environmental geology,regional geology and new  相似文献   

7.
报道了甘肃礼县鲁班石地区石炭纪地层中新获得牙形刺化石14属26种,其中12属22种为新发现,包括:Declinognathodus laterahs, D. noduliferus noduliferus, Gnathodus bilineatus costiformis, G. bilineatus bilineatus,Gondolella gymna, G. xinjiangensis, Neognathodus bassleri, Neoprioniodus barbatus, ldiognathodus claviformis, I.delicatus, I. klapperi, ldiognathoides sinuatus, I. sulcatus, Lochriea commutata, Ligonodina typa, Lonchodina tarimensis, L. bischoffi, Lonchodus simplex, Streptognathodus expansus, S. parvus, S. suberectus, Ozarkodina hindei。其中Streptognathodus , Declinognathodus , Neognathodus ,Idiognathodus和Idiognathoides5属是上石炭统下部的代表分子,Streptognathodus gracilis和Gondolella属是上石炭统上部的代表分子。  相似文献   

8.
量 锗误的符号 正确的符号长度KM.KMS,千公尺km,千米 M,公尺m,米 公寸,分米0* 公分cm,厘米 MM,m/m,公厘 mm,毫米 p.pM,mp pm.徽米 dmm.丝米0.olmm,I00Am cmm,忽米 0.OImm.10pm mpm,毫裕米urn,纳米面积 KMZ,sq·kin kmZ(平方公里)体积 公升,立升L,1.升 立方,立米m3米’ CC,C·C·ml,mL.毫升时间·Y.yr a,年 date d,日 hr h,时 (omi,分 (”).SC,S S,秒量 铝课的符号 正确的符号质量T,公吨t,吨 KG,Kg kg,千克,讼斤) gr,gm g碗温度”K.开氏度 K.开速度 秒米,每秒米m/s,米/秒体积哉量 秒立米,立方米/秒m’/s,米’/秒物质的员 克分…  相似文献   

9.
张瑛 《辽宁地质》1999,16(4):301-305
宛甸县处于新构造运动强烈上升区,境内峰峦叠嶂,山势陡峻,沟深谷狭,暴雨频繁地质环境十分脆弱,加之森林大量砍伐,陡坡开荒严重,垦植指数过高,超载养蚕放牧,滥采乱挖猖獗,使生态环境遭到严重破坏,水土流换程度日益加剧,严重的水土人,导致水库淤积,河道堵塞,土层变薄,地力下降,洪水泛滥,灾害频繁,给国民经济和社会发展造成巨大损失,本文阐述了宽甸山区水土流失的形成因素和危害现状,并因地制宜提出了水土流失灾害的防治对策。  相似文献   

10.
正1.Papers should be devoted mainly to various aspects of research concerning geosciences and related disciplines in China,such as stratigraphy,paleontology,origin and history of the Earth,structural geology,tectonics,mineralogy,petrology,geochemistry,geophysics,geology of mineral deposits,hydrogeology,engineering geology,environmental geology,regional geology and new theories  相似文献   

11.
Well investigated platforms have been selected in each continent, and the history of Cretaceous transgressions and regressions there is concisely reviewed from the available evidence. The factual records have been summarized into a diagram and the timing of the events correlated between distant as well as adjoining areas.On a global scale, major transgressions were stepwise enlarged in space and time from the Neocomian, via Aptian-Albian, to the Late Cretaceous, and the post-Cretaceous regression was very remarkable. Minor cycles of transgression-regression were not always synchronous between different areas. Some of them were, however, nearly synchronous between the areas facing the same ocean.Tectono-eustasy may have been the main cause of the phenomena of transgression-regression, but certain kinds of other tectonic movements which affected even the so-called stable platforms were also responsible for the phenomena. The combined effects of various causes may have been unusual in the Cretaceous, since it was a period of global tectonic activity. The slowing down of this activity followed by readjustments may have been the cause of the global regression at the end of the Cretaceous.  相似文献   

12.
The Afyon stratovolcano exhibits lamprophyric rocks, emplaced as hydrovolcanic products, aphanitic lava flows and dyke intrusions, during the final stages of volcanic activity. Most of the Afyon volcanics belong to the silica-saturated alkaline suite, as potassic trachyandesites and trachytes, while the products of the latest activity are lamproitic lamprophyres (jumillite, orendite, verite, fitztroyite) and alkaline lamprophyres (campto-sannaite, sannaite, hyalo-monchiquite, analcime–monchiquite). Afyon lamprophyres exhibit LILE and Zr enrichments, related to mantle metasomatism.  相似文献   

13.
正20140751 Guo Xincheng(Geological Party,BGMRED of Xinjiang,Changji 831100,China);Zheng Yuzhuang Determination and Geological Significance of the Mesoarchean Craton in Western Kunlun Mountains,Xinjiang,China(Geological Review,ISSN0371-5736,CN11-1952/P,59(3),2013,p.401-412,8  相似文献   

14.
正20141058 Chen Ling(Key Laboratory of Mathematical Geology of Sichuan Province,Chengdu University of Technology,Chengdu610059,China);Guo Ke Study of Geochemical Ore-Forming Anomaly Identification Based on the Theory of Blind Source Separation(Geosci-  相似文献   

15.
SEISMIC GEOLOGY     
正20141334 Chen Kun(Institute of Geophysics,China Earthquake Administration,Beijing100081,China);Yu Yanxiang Shakemap of Peak Ground Acceleration with Bias Correction for the Lushan,Sichuan Earthquake on April20,2013(Seismology and Geology,ISSN0253-4967,CN11-2192/P,35(3),2013,p.627-633,2 illus.,1 table,9 refs.)Key words:great earthquakes,Sichuan Province  相似文献   

16.
正20141624 Cai Xiongfei(Key Laboratory of Geobiology and Environmental Geology,Ministry of Education,China University of Geosciences,Wuhan 430074,China);Yang Jie A Restudy of the Upper Sinian Zhengmuguan and Tuerkeng Formations in the Helan Mountains(Journal of Stratigraphy,ISSN0253-4959CN32-1187/P,37(3),2013,p.377-386,5 illus.,2 tables,10 refs.)  相似文献   

17.
PALEONTOLOGY     
正20142263Lü Shaojun(Geological Survey of Jiangxi Province,Nanchang 330030,China)Early-Middle Permian Biostratigraphical Characteristics in Qiangduo Area,Tibet(Resources SurveyEnvironment,ISSN1671-4814,CN32-1640/N,34(4),2013,p.221-227,2illus.,2tables,22refs.)Key words:biostratigraphy,Lower Permian,Middle Permian,Tibet  相似文献   

18.
正20142560Hu Hongxia(Regional Geological and Mineral Resources Survey of Jilin Province,Changchun 130022,China);Dai Lixia Application of GIS Map Projection Transformation in Geological Work(Jilin Geology,ISSN1001-2427,CN22-1099/P,32(4),2013,p.160-163,4illus.,2refs.)  相似文献   

19.
GEOCHEMISTRY     
正20140692 Duo Tianhui(No.402 Geological Team,Exploration of Geology and Mineral Resources of Sichuan Authority,Chengdu611730,China);Wang Yongli Computer Simulation of Neptunium Existing Forms in the Groundwater(Computing Techniques for Geophysical and Geochemical Exploration,ISSN1001-1749,CN51-1242/P,35(3),  相似文献   

20.
正20140876 Gao Junbo(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China);Yang Ruidong Study on the Strontium Isotopic Composition of Large Devonian Barite Deposits from Zhenning,Guizhou Province(Geochimica,  相似文献   

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