Table Of Content

SPECIAL ISSUE PRECAMBRIAN GRANITOIDS Petrogenesis, Geochemistry and Metallogeny Papers presented at the Symposium on Precambrian Granitoids — Petrogenesis, Geochemistry and Metallogeny, held August 14-17, 1989 in Helsinky, Finland Edited by I. Haapala* and K.C. Condie? *Department of Geology, Division of Geology and Mineralogy, University of Helsinki, Box 115 SF 00171, Finland >Department of Geoscience, New Mexico Institute of Mining and Technology, Socorro, NM 87801, USA CONTENTS NI sss crassaz i acs kai ncaa pas estan eae tcde nd cea id aiet oe esa tess oie a Sabena ls eee igi ade daanhcs leita Vii Partial melting of amphibolite/eclogite and the origin of Archean trondhjemites and tonalites R.P. Rapp, E.B. Watson (Troy, NY, USA) and C.F. Miller (Nashville, TN, USA) l The Alneau Batholite: Archean diapirisim preceded by coalescence of granitoid magma at depth L.D. Ayres, N.M. Halden (Winnipeg, Man., Canada) and D.V. Ziehlke (Snow Lake, Man., Canada) 27 An overview oft he nature, distribution and inferred tectonic setting of granitoids in the late-Archean Norseman—Wiluna Belt K.F. Cassidy, M.E. Barley, D.1. Groves, C.S. Perring (Nedlands, W.A., Australia) and J.A. Hallberg (Neerabup, W.A., Australia) The “porphyry-gold” association in the Norseman—Wiluna Belt of Western Australia: implications for models of Archean gold metallogeny C.S. Perring (Wembley, W.A., Australia), D.I. Groves (Nedlands, W.A., Australia), J.N. Shellabear (Perth, W.A., Australia) and J.A. Hallberg (Neerabup, W.A., Australia ) Generation oft rondhjemite from partial melting of dacite under granulite facies conditions: an example from the New Jersey Highlands, USA J.H. Puffer (Newark, NJ, USA) and R.A. Volkert (Trenton, NJ, USA) Granitoid episodes and mafic-felsic magma interaction in the Svecofennian of the Fennoscandian Shield, with main emphasis on the ~ 1.8 Ga plutonics U.B. Andersson (Uppsala, Sweden ) Structural features of some younger granitoids in central Sweden and implications for the tectonic subdivision of granitoids A. Wikstr6m (Uppsala, Sweden) Precambrian granulites and anorogenic granites: are they related? K.C. Kondie (Socorro, NM, USA) Granitoids of rapakivigranite—anorthosite and related associations R.F. Emslie (Ottawa, Ont., Canada) Makhavinekh Lake Pluton, Labrador, Canada: geological setting, subdivisions, mode of emplacement, and a comparison with Finnish rapakivi granites B. Ryan (St. John’s, NF, USA) New U-Pb ages from the Wiborg rapakivi area: constraints on the temporal evolution oft he rapakivi granite- anorthosite—diabase dyke association of southeastern Finland M. Vaasjoki (Espoo, Finland), T. Ram6 (Helsinki, Finland) and M. Sakko (Espoo, Finland) The Butler Hill Caldera: a mid-Proterozoic ignumbrite-granite complex AST ei A eine NN TON oa cncc ceca cgekce a vases oasicus vousavexe sdvsesaancntotouanacenactesnistinenasVasaiaseatelapaegaveniseterte 245 Lead isotopic evidence for the origin of 1.8-1.4 Ga ores and granitoids in the southeastern part of the Fennoscandian Shield Is CanesRe c cer NINN SINE has aca Gadde kev na ela viannbavdaesansadica SleespRRaU UR Rote Oras ea AON The Ititba alkaline syenite massif, Bahia State (Brazil): mineralogical geochemical and petrological constraints — relation to the genesis of rapakivi magmatism H. Conceicdo, P. Sabate (Salvador, Brazil) and B. Bonin (Orsay, France) .............:.scssssssssssesssecececsssceceecneecsesssesesesseceesssees 209 Grenvillian magmatism in the eastern Grenville Province, Canada C.F. Gower (St. John’s, NF, USA), L.M. Heaman (Toronto Ont., Canada), W.D. Loveridge (Ottawa, Ont., Canada), U. Scharer (Montreal, Canada) and R.D. Tucker (Toronto, Ont., Camada) ..............cccssscesseeeesceeeeeeeeeeeeeeeeseees 315 CONTENTS U-Pb dating of the post kinematic Sveconorwegian (Grenvillian ) Bohus granite, SW Sweden: evidence of restitic zircon T. Eliasson (Géteborg, Sweden ) and H. Schéberg (Stockholm, Sweden )....................cccscccssccsssscosesscesscsesesenssesccsccssssssscssees SOT Late Proterozoic granitoid magmatism in the state of Sao Paulo, southeastern Brazil ee a IRI Ae, COI A TD IN IE 9n oes csecencovecesarcinvenavestecnssecsssvnusosundosorstcusneseedetbadbevssoabesnsaoeusne 351 Late Proterozoic fractionated granitoids of the mineralized Telfer area, Paterson Province, Western Australia N.M. Goellnicht, D.I. Groves and N.J. McNaughton (Nedlands, W.A. Australia ) ............c:cescssseecsceesseseeeeeseneeeneeeneeeeneees 375 The Cadomian granites of Mancellia, northeast Armorican Massifo f France: relationship to the St. Malo migmatite belt, petrogenesis and tectonic setting M. Brown (Kingston-upon-Thames, UK) and R.S. D’Lemos (Oxford, UK) 0.0... ceceeceesceeseeeeesesseenaceeseseasseeeeeeesseeseneeens 393 Fertile granites of Precambrian rare-element pegmatite fields: is geochemistry controlled by tectonic setting or source lithologies? P. Cerny (Winnipeg, Man., Canada) Sf322 8ZEES2BR5B AE SSRE SRLSSeUAAeREA RIAnSlS l e Precambrian Granitoids Symposium participants on the stairs of the Cathedral of Helsinki, Finland.