简介：<正>OXIDESANDTRACEELEMENTSOFTHECARBONIFEROUSCARBONATEROCKINTIANSHANMT.,CHINAZhangQinhua,QinQingxiangandWeiZhouling(ChangshaInstituteofGeotectonics,AcademiaSinica,Changsha,410013,Hunan,China)oxide,traceelement,carbonaterock,Carboniferous,TianshanMt.TheCarboniferouscarbonaterockwithcomplicatedcompositionandvariousrocktypesandlithofaciesdevelopswellinTianshanMt.,China,andplaysanimportantroleinthestudyoftectonicsandmetallogenyinthearea.Thecontentandvariationcharacteristicsofmainpxidesandelementsareillustratedherebasedonagreatamountofgeochemicaldata.

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简介：ThispapersummarisesthegeologicalfeaturesoftheLarderello-TravaleandMonteAmiataareas,wheretheworld'smostancientexploitedgeothermalfieldsarelocated.Inbothgeothermalareas,threeregionaltectonostratigraphicelementsaredistinguished,fromthetop:(a)LateMiocene-PlioceneandQuaternary,continentaltomarinesediments;(b)theLigurianandSub-Liguriancomplexes,whichincluderemnantsoftheJurassicoceanicrealmandofthetransitionalareatotheAdriaticmargin,respectively;(c)theTuscanUnit(TuscanNappe),composedofsedimentaryrocksrang-inginagefromLateTriassictoEarlyMiocene.Thesub-stratumoftheLarderelloandMonteAmiataareasisreferredtoastheTuscanMetamorphicComplex.Thisismainlyknownthroughdrillingofgeothermalwells.Thiscomplexiscomposedoftwometamorohicunits:theupperMonticiano-RoccastradaUnitandthelowerGneissComplex.TheMonticiano-RoccastradaUnitconsistsof(fromtoptobottom):theVerrucanoGroup,thePhyllite-QuartziteGroupandtheMicaschistGroup.TheGneissComplexconsistsonlyofpre-Alpinepoly-metamorphicgneiss.TheTuscanMetamorphicComplexisaffectedbycontactmetamorphismbyPlio-Quater-narygranitoidsandtheirdykeswarms.Hydrothermalphenomenastilloccurinbothgeothermalfields.TheLarderello-TravaleandMt.AmiatageothermalfieldsarelocatedintheinnerNorthernApennines,inanareathathasbeensubjecttoextensionsincethe?Early-Mid-dleMiocene.Twomainextensionaleventsarewellexpressedinthestructuresofthegeothermalareas.Thefirstextensionalevent(?Early-MiddleMiocene)deter-minedthetectonicdelaminationoftheLigurianUnitsandTuscanNappe.Thesecondextensionalevent(LateMiocene-Present)ischaracterizedbyhigh-anglenor-malfaultsboundingtheNeogenetectonicdepressionsofsouthernTuscany.

简介：Manysmallmountainglaciershavebeenreportedundergoingstrongshrinkage,anditisthereforeimportanttounderstandhowtheyrespondtoclimatechange.Theavailabilityoftopographicmapsfrom1962,LandsatTMimageryfrom1990andASTER(AdvancedSpaceborneThermalEmissionandRadiometer)imageryfrom2006andfieldinvestigationofsomeglaciersallowacomprehensiveanalysisofglacierchangebasedonglaciersizeandtopographyonMt.Bogda.Resultsinclude:(1)anoveralllossofaglacierizedareaby31.18±0.31km~2or21.6%from1962to2006,(2)amarkeddependenceofglacierareashrinkageoninitialsize,withsmallerglaciersexperiencinghighershrinkagelevels,(3)thedisappearanceof12smallglaciers,(4)astrikingdifferenceinarealossbetweenthesouthernandnorthernslopesof25%and17%,respectively.Asubsetoftheinvestigatedglaciersshowsthatthearea57.45±0.73km2in1962reducedto54.79±0.561km~2in1990and48.88±0.49km~2in2006,witharelativeareareductionof4.6%during1962–1990,and10.8%during1990–2006.Thecorrespondingvolumewasteincreasedfrom6.9%to10.2%.Threereferenceglacierswereinvestigatedin1981andrevisitedin2009.Theirterminusexperiencedamarkedrecession.MeteorologicaldatafromstationsaroundMt.Bogdarevealsthatglaciershrinkageiscorrelatedwithwinterwarmingandanextensionoftheablationperiod.Precipitationonthenorthwestsideoftherangeshowsamarkedincrease,withaslightincreaseonthesoutheastside.

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简介：利用大地电磁测深法（MT）反映地质体的电性差异，首先可以确定地质体的空间展布、地质结构和构连；而由于地质体电阻率受地热水影响而降低，进而据此圈定地热水的分布范围；并在此基础上可以进一步探讨地热形成机制。在华北地台地热勘探中MT法取得了较好的勘探效果。