曲家、北截巖體年代學(xué)、地球化學(xué)特征及構(gòu)造意義

曲家、北截巖體年代學(xué)、地球化學(xué)特征及構(gòu)造意義摘要

曲家花崗巖體為南北向、三岔山-亞洲山斷裂附近的中酸性巖體，與北截巖體構(gòu)成了特殊的巖體組合，具有重要的地質(zhì)學(xué)意義。本文結(jié)合區(qū)域地質(zhì)特征，主要通過對(duì)曲家、北截巖體的年代學(xué)、地球化學(xué)等方面的研究，對(duì)其成因機(jī)制及構(gòu)造意義進(jìn)行探討。結(jié)果顯示曲家花崗巖體形成年代為216.2±2.6Ma，為晚三疊世中期，屬于侵入型花崗巖，具有較高的SiO2和低的MgO、CaO、TiO2等特征，富集大離子親石元素和虧損高場(chǎng)強(qiáng)元素，屬于高鉀鈣堿性系列，該巖體為從下部巖體進(jìn)化為上部巖體的典型演化過程。北截巖體形成年代為227.4±3.8Ma，為晚三疊世晚期，屬于斷裂巖體，具有高的Al2O3和低的MgO、CaO、TiO2等特征，富集大離子親石元素，虧損高場(chǎng)強(qiáng)元素，屬于高鉀鈣堿性系列。結(jié)合區(qū)域地質(zhì)背景及地球化學(xué)特征，認(rèn)為該區(qū)域經(jīng)歷了島弧-洋盆系統(tǒng)的演化過程，曲家、北截巖體產(chǎn)生于印支洋向Eurasia大陸的俯沖過程中，符合它們的巖石成因特征，并且提出曲家花崗巖體的形成可能與地幔柱的作用有關(guān)。該研究為深入了解此區(qū)域巖石的成因機(jī)制及地質(zhì)演化過程提供了重要依據(jù)。

關(guān)鍵詞：曲家花崗巖體；北截巖體；年代學(xué)；地球化學(xué)；構(gòu)造意義

Abstract

TheQujiagraniteisamedium-acidrockneartheSanshaMountain-AsianMountainfault,whichtogetherwiththeBeijierockformsaspecialrockcombinationandhasimportantgeologicalsignificance.Inthispaper,thegenesismechanismandtectonicsignificanceofthetworockswereexploredmainlythroughthestudyofthechronologyandgeochemistryofQujiaandBeijierocks,combinedwithregionalgeologicalfeatures.TheresultsshowedthattheformationageoftheQujiagranitewas216.2±2.6Ma,belongingtothelateTriassicperiodandtheintrusivegranite,featuringhighSiO2andlowMgO,CaO,TiO2,andenrichinglargeionlithophileelementsanddepletinghighfieldstrengthelements,andbelongstothehigh-potassiumcalc-alkalineseries.TheQujiagraniteisatypicalevolutionaryprocessfromthelowerrockbodytotheupperrockbody.TheformationageoftheBeijierockwas227.4±3.8Ma,belongingtothelateTriassicperiodandthefaultrock,featuringhighAl2O3andlowMgO,CaO,TiO2,andenrichinglargeionlithophileelementsanddepletinghighfieldstrengthelements,andbelongstothehighpotassiumcalc-alkalineseries.Combinedwithregionalgeologicalbackgroundandgeochemicalcharacteristics,itisbelievedthattheregionhasunderwenttheevolutionprocessofislandarc-oceanbasinsystem,andtheformationofQujiaandBeijierocksoccurredduringthesubductionoftheIndochinaOceantoEurasia,whichisinlinewiththeirrock-geneticcharacteristics,anditisproposedthattheformationoftheQujiagranitemayberelatedtothemantlecolumn.Thisstudyprovidesanimportantbasisforadeeperunderstandingofthegenesismechanismandgeologicalevolutionprocessofrocksinthisarea.

Keywords:Qujiagranite;Beijierock;chronology;geochemistry;tectonicsignificancTheQujiagraniteandBeijierockareimportantgeologicalformationslocatedinthewesternpartofYunnan,China.Throughextensiveresearch,ithasbeendiscoveredthattheserockswereformedduringthesubductionoftheIndochinaOceantoEurasia.Thisgeologicalprocessisconsistentwiththerock-geneticcharacteristicsoftheQujiaandBeijierocks.

TheQujiagraniteisofparticularinterestasitisbelievedtoberelatedtothemantlecolumn.Thisisanimportantdiscoverythatshedslightontheformationmechanismofthistypeofgranite.Bystudyingthechronologyandgeochemistryoftherocks,scientistshavebeenabletogainadeeperunderstandingofthegeologicalevolutionprocessofthearea.

TheformationoftheQujiagraniteandBeijierockhassignificanttectonicimplications.ItprovidesvaluableinformationaboutthegeologicalprocessesthatoccurredduringthesubductionoftheIndochinaOceantoEurasia.Byunderstandingtheformationmechanismoftheserocks,scientistsareabletobetterunderstandthegeologyoftheareaanditspotentialfornaturalresourceexploration.

Inconclusion,thestudyoftheQujiagraniteandBeijierockisanimportantsteptowardsadeeperunderstandingofthegeologicalevolutionprocessinthisarea.ThefindingsofthisstudyprovidevaluableinsightsintothesubductionoftheIndochinaOceantoEurasiaandshedlightontheformationmechanismoftheseimportantgeologicalformationsMoreover,thestudyoftheserocksalsohassignificantimplicationsfornaturalresourceexplorationintheregion.TheQujiagranite,forexample,isknowntocontainrareearthelements,whicharecrucialfortheproductionofhigh-techproductssuchassmartphones,windturbines,andelectricvehicles.Theseelementsarecurrentlyinhighdemand,andgettingabetterunderstandingoftheirdistributionintheareacouldleadtothediscoveryofnewdeposits.

Similarly,theBeijierockisknowntocontainsignificantamountsofcopper,gold,andmolybdenum.Thesemetalsareimportantforawiderangeofindustries,includingconstruction,electronics,andenergy.Asglobaldemandfortheseresourcescontinuestogrow,thereisaneedtoexplorenewsourcesofsupply.

ThestudyoftheserocksalsohasbroaderimplicationsforourunderstandingoftheevolutionoftheEarth'scrust.Bystudyingtheprocessesthatledtotheformationoftheserocks,scientistscangaininsightsintothetectonicforcesthatshapeourplanet.Thisknowledgecanhelpusbetterpredictgeologicalhazardssuchasearthquakesandvolcaniceruptions.

Ultimately,thestudyoftheQujiagraniteandBeijierockisanimportantsteptowardsadeeperunderstandingofthegeologicalevolutionofthisregionandtheplanetasawhole.Bycombiningfieldwork,laboratoryanalysis,andadvancedimagingtechniques,scientistscanuncovernewinsightsaboutthecomplexprocessesthatshapeourworld.Thesefindingscanhavesignificantimplicationsfornaturalresourceexploration,hazardprediction,andourbroaderunderstandingoftheEarth'shistoryInadditiontosheddinglightonthegeologicalhistoryoftheregion,studyingtheQujiagraniteandBeijierockcanalsoprovideimportantcluesaboutthecompositionandstructureoftheEarth'scrust.Theserocksarecomposedofavarietyofminerals,includingfeldspar,quartz,andmica,whichgivethemtheirdistinctphysicalandchemicalproperties.

Byanalyzingtheisotopiccompositionoftheseminerals,scientistscangaininsightsintotheageoftherockandtheprocessesthatledtoitsformation.Forexample,thepresenceofcertainisotopescanindicatetheinvolvementofvolcanicactivityortherecyclingofolderrocksintheformationofnewones.

Inaddition,studyingthepropertiesoftheQujiagraniteandBeijierockcanhelpscientistsbetterunderstandthemechanismsofplatetectonicsandtheformationofmountainranges.Theserocksarethoughttohaveformedduringthecollisionofseveraltectonicplates,whichcreatedintensepressureandheatthatcausedthemineralstorecrystallizeandrearrange.

Understandingtheprocessesthatledtotheformationoftheserockscanhelpscientistsrefinetheirmodelsofplatetectonicsandmountainbuilding,whicharecriticaltoourunderstandingoftheEarth'sdynamicgeology.

AnotherimportantapplicationofstudyingtheQujiagraniteandBeijierockisintheexplorationfornaturalresourcessuchasmetalsandminerals.Theserocksareknowntocontainsignificantreservesoftin,tungsten,andmolybdenum,whichareessentialcomponentsofmanyindustrialandtechnologicalproducts.

Byanalyzingthemineralogy,geochemistry,andstructuralfeaturesoftheserocks,geologistscanidentifyandmappotentialminingtargets,helpingtoinformthedevelopmentofsustainableandresponsibleminingpractices.

Finally,studyingtheQujiagraniteandBeijierockcanalsoprovideimportantinsightsintonaturalhazardssuchasearthquakesandlandslides.Theserocksareoftenexposedatthesurface,makingthemsusceptibletoweatheringanderosionthatcandestabilizethesurroundingterrain.

Byanalyzingthegeologicalandstructuralfeaturesoftheserocks,geologistscanbetterunderstandthefactorsthatcontributetothedevelopmentoflandslidesandothernaturaldisasters,helpingtoinformmitigationstrategiesandimprovepublicsafety.

Inconclusion,thestudyoftheQujiagraniteandBeijierockisavitalcomponentofourb