摘要
辽宁省广泛发育元古宙侵入岩,它们具有成分及结构演化不同特征。应用岩石谱系单位划分、归并的原则,划分单元25个,归并超单元6个,非正式单位杂岩8个。总结出古元古代侵入岩与辽东裂谷形成与演化密切相关,经历了造山前超基性→基性、造山期中酸性→酸性、造山后构造崩塌期基性→中性→酸性,钠质→钾质岩浆演化规律及大陆动力学演化过程;中元古代及新元古代侵入岩形成于陆块区及陆缘活动带区两种构造背景。提出了元古宙侵入岩成因类型有幔源、壳幔混源、壳源。
InLiaoningprovince,therearewidelydevelopedProterozoicintrusiverockswithmainlyfrombasictoacidiccompositionevolutioncharacteristicsandfromfinetocoarsetextureevolusioncharacteristiocs.Basedonthesubdivisionandincoperationprinciplesofrocklineageunits,theProterozoicintrusiverocksinLiaoningprovincecanbesubdividedinto25units,whichareincorporatedinto6ultra-units,andalso8complexes. PaleoproterozoicLüliangperiodintrusiverocks,closelyrelatedwithEastLiaoningRift,aremainlydistributedinYingkou,Dandong,Kuandian,Huairen,etc.,tothesouthofTaitzeRiverDepression.Throughpreorogenic,orogenicandpostorogenictectoniccollapsingperiodsevolution,thegeneraltradeofmagmaticevolutionisfromultrabasictobasictoacid,fromtholeiitetocalc-alkalineseries,fromagpaitictopotassic,andthemagmaticactivitieshavethecharacteristicsofmultiplecycles.Mid-proterozoicSipuperiodintrusiverocksandNeoproterozoicJiningperiodintrusiverocksaremainlydistributedindifferentgeotectonicunitsofWestLiaoningLandmassandNorthLiaoningEpicontinentalActiveBelts.Inpreorogenicperiod,magmagenerallyevolvedfromultrabasictobasictointermedium;inorogenicperiod,magmafrommediumacidtoacidorintermediumtoacid;inpostorogenicperiod,magmafrombasictointermediumtoacid.
关键词
元古宙
侵入岩
岩石谱系单位
成因类型
构造环境
Proterozoic
intrusiverock
rocklineageunit
genesistype
tectonicenvironment