简介：0IntroductionTheJapaneseIslandsconsistoffivevolcanicarcs(Fig.1).TheNorth-EastandSouthWestJapanarcstogetherformtheHonshuarc,towhichtheKurilearcjoinsatHokkaido,whereastheIzu-MarianaarcjoinsatIzu-FossaMagna,andtheRyukyuarcjoinsatKyushu.Theseregionswherevolcanicarcsconverge,aretermed'islandarcjunctions'.

简介：1.ObjectivesKeeryinraremetaloredistrictislocatedattheintersectionofMarkam,JinchuanandRangtangcounties.Morethan1000pegmatitedykesareassociatedwiththeKeeryingranitepluton.Thesepegmafitedykesarethemajorsourceofindustrialspodumeneorebodies.Basedonthepreviousstudies,wechoseKeeryinraremetaloredistrictasthekeytargetareaforgeologysurvey.Inthisstudy,wediscoveredsixpegmatitelithiumveinsintheSizemuzudistrictoftheKeeryin.Moreover,westudythedistributionofregionaloredepositsandmetallogeny,delineateprospectingtargetandevaluatethemineralizationpotentialofLithium.

简介：ObjectivesToassessedthefeasibilityandeffectivenessofelectrophysiologicalmappingofpulmonaryveinswithacircumferential10-electrodecatheterandradiofrequencycatheterablationtherapyforpatientswithparoxysmalatrialfibrillation.BackgroundStandardmappingandablationoffocalsourcesofatrialfibrillationareassociatedwithverylongproceduretimesandlowefficacy.Mappingandablationpulmonaryveinsguidewithacircularcathetercouldovercometheselimitations.Methods16patients[male11,female5,meanage(51±14.5)years]withparoxysmalatrialfibrillationrefractorytoantiarrhythmicdrugswereincludedinthisgroup.Acircumferential10-electrodecatheterwasusedtopulmonaryveinmappingduringsinusrhythmorCSdpacingtodeterminetheoriginofatrialprematurecontractions.Whentheablativetargetpulmonaryveinwasfound,thepulmonaryveinpotentials’distributionandactivationwereassessmentpulmonaryveins’ostialablationwasperformedattheseg

简介：TheYangshangolddepositisasuper-largefine-graineddisseminatedgolddepositlocatedinsouthernGansuProvince.ItsmetallogenicagehasbeendeterminedbyusingthecathodoluminescenceimageandionprobeU-Pbdatingtechniques.Itisfoundthatzirconsfromquartzveinletofthefine-graineddisseminatedgoldoreshowcharactersofmagmaticoriginwithprismidiomorphism,oscillatoryzoninganddominantTh/Uratiosof0.5-1.5.Threemainpopulationsofzirconsareobtained,givingaverage206pb/238Uagesof197.6±1.7Ma,126.9±3.2Maand51.2±l.3Marespectively.ThefirstagecorrespondstotheK-Arageoftheplagiogranitedike,whilethelattertwoagesindicatethatburiedCretaceousandTertiaryintrusivesexistintheorefield,suggestingthattheYangshangolddepositwasgeneticallyrelatedtothethreemagmatichydrothermalactivities.Bycontrast,zirconsfromcoarsegold-bearingquartzveinintheminingareaaremucholderthanthehostrock,indicatingthattheveinwasformedearlierandwasnotcontaminatedbylatermagmaticfluids.ItisconcludedthatthecouplingofmultiperiodichydrothermalactivitiesintheminingareahascontributedalottomineralizationoftheYangshangolddeposit.

简介：TheShihugolddeposit,situatedintheTaihangMesozoicorogenoftheNorthChinaCraton(NCC),ishostedbyductile-brittlefaultswithinArcheanmetamorphiccorecomplex.Thedepositischaracterizedbygold-bearingquartz-polymetallicsulfidesveins.TheMapenggranitoidsstockandintermediate-basicdikesintrudedthemetamorphicbasementrocks,andarespatiallyrelatedtogoldmineralization.Detailedlaserablationinductivelycoupledplasmamassspectrometry(LAICP-MS)U-Pbzirconagesofthegraniticrocks,dykesandmineralizedquartzveinsinthestudiedarearevealitsmagmaticandmineralizedhistory.Themineralizedquartzveinscontaininheritedzirconswithagesofabout2.55Gaand1.84Ga,probablycomingfromthebasement.ThesetwoPrecambrianeventsarecoevalwiththoseinotherpartsoftheNCC.TheMapenggranitoidstock,thelargestintrusioninthearea,wasemplacedatca.130Ma,andiscoevalwithmagmaticzirconpopulationsfromdioritesandquartzdioritepophyritesinthesameregion.Theca.130MamagmatismandgoldmineralizationweremostlikelyrelatedtoanunderplatingeventthattookplaceintheTaihangorogenatLateMesozoic.Thetimingofgoldmineralizationwithrespecttofelsicmagmatismintheareaissimilartothoseobservedinothermajorgold-producingprovincesintheNCC.ThisepisodeissimultaneouswiththoseintheeasternmarginofNCC,indicativeofawidespreadlateYanshanianmetallogeniceventthatwasaresponsetotheEarlyCretaceouslithosphereintheeasternNCC,inwhichthemesothermalgolddepositswereformedfromsimilartectono-magmaticenvironments.