The generation of the continental crust is widely accepted to have taken place predominantly in the Archean,when TTG magmatism associated with greenstone-belt supracrustal succession development was typically followed by emplacement of high-K granites before crustal stabilization.This study focuses on the Campos Gerais complex(CGC),which is an Archean granite-greenstone belt lithological associa-tion in a tectonic window located in the southwesternmost portion of the S?o Francisco craton(SFC).The CGC is an important segment of Paleo-to Mesoarchean continental crust to be integrated into pale-ogeographic reconstructions prior to the transition into the Paleoproterozoic.This investigation reports field relationships,28 major and trace element compositions,U-Pb(zircon)geochronological results,and Hf and Sm-Nd isotope data for orthogneiss and amphibolite samples.The results indicate that the CGC records a complex Archean crustal evolution,where voluminous 2.97 Ga TTG tonalites and trond-hjemites(εNd(t)=-4.7;TDM=3.24 Ga)were followed by 2.89 Ga sanukitoid tonalite production(εNd(t)=-1.9;TDM=3.02 Ga),broadly coeval with the development of the Fortaleza de Minas and Pitangui greenstone-belts.These events are interpreted to represent the initial stage of an important subduction-accretion tectonic cycle,which ended with the emplacement of 2.82-2.81 Ga high-K leucogranites and migmatization of the TTG-sanukitoid crust,with hybrid and two-mica,peraluminous compositions(εNd(t)=-8.0 to-8.6;TDM=3.57-3.34 Ga).The presence of inherited zircons with 207Pb/206Pb ages of 3.08 Ga,3.29 Ga,3.55 Ga and 3.62 Ga indicates that the Mesoarchean tectonic pro-cesses involved reworking of Meso-to Eo-archean crust.Renewed TTG magmatism took place at ca.2.77 Ga represented by juvenile tonalite stocks(ENd(t)=+1.0 to-1.5;TDM=2.80-2.88 Ga)which intrude the TTG-greenstone belt association.Crustal stabilization was attained by 2.67 Ga,allowing for the emplacement of within-plate tholeiitic amphibolites(ENd(t)=-3.1;TDM=2.87 Ga).The CGC shows important tectonic diachronism with respect to other Archean terrains in the southern S?o Francisco cra-ton,including an independent Meso-to Neoarchean crustal evolution.

Claudio de Morisson Valeriano;Caio Vinicius Gabrig Turbay;Henrique Bruno;Antonio Simonetti;Monica Heilbron;Samuel Moreira Bersan;Rob Strachan

Universidade do Estado do Rio de Janeiro,Faculdade de Geologia,Rua S?o Francisco Xavier 524/4006-B,Maracan?,Rio de Janeiro,Brazil;Universidade Federal do Sul da Bahia,Centro de Forma??o em Ciências Ambientais,Porto Seguro,Bahia,Brazil;University of Portsmouth,School of Environment,Geography and Geosciences,Burnaby Building,Burnaby Road,Portsmouth PO1 3QL,United Kingdom;University of Notre Dame,Department of Civil and Environmental Engineering and Earth Sciences,46556,United States

地学前缘（英文版）

[1]Claudio de Morisson Valeriano;Caio Vinicius Gabrig Turbay;Henrique Bruno;Antonio Simonetti;Monica Heilbron;Samuel Moreira Bersan;Rob Strachan-.Paleo-and Mesoarchean TTG-sanukitoid to high-K granite cycles in the southern S?o Francisco craton,SE Brazil)[J].地学前缘（英文版）,2022(05):153-168

Mesoarchean,sanukitoid,Campos,southwesternmost,ogeographic,tonalites,trond,hjemites,Fortaleza,Pitangui,migmatization,archean,Renewed,intrude,tholeiitic,amphibolites,diachronism

TTG,high,cycles,southern,Francisco,craton,SE,Brazil,generation,continental,widely,accepted,have,taken,predominantly,Archean,when,magmatism,associated,greenstone,supracrustal,succession,development,was,typically,followed,by,emplacement,before,stabilization,This,study,focuses,Gerais,complex,CGC,which,lithological,tectonic,window,located,portion,SFC,important,segment,integrated,into,pale,reconstructions,prior,transition,Paleoproterozoic,investigation,reports,field,relationships,major,trace,element,compositions,geochronological,results,Hf,Sm,isotope,data,orthogneiss,samples,that,records,evolution,where,voluminous,Ga,TDM,were,production,broadly,coeval,Minas,belts,These,events,are,interpreted,initial,stage,subduction,accretion,ended,leucogranites,hybrid,two,mica,peraluminous,presence,inherited,zircons,207Pb,206Pb,ages,indicates,cesses,involved,reworking,Eo,took,represented,juvenile,stocks,ENd,+1,association,Crustal,attained,allowing,within,plate,shows,respect,other,terrains,including,independent,Neoarchean

0.41672