Province of British Columbia MINERAL RESOURCES DIVISION Ministry of Energy, Mines and Geological Survey Branch Petroleum Resources Hon. Anne Edwards, Minister CARBONATITES, NEPHELINE SYENITES, KIMBERLITES AND RELATED ROCKS;IN BRITISH COLUMBIA This is a Contribution to the CanaddBritish Columbia Mineral Development Agreement1985-1990 By Jennifer Pel1 BULLETIN 88 Canadian~~ ~~~~~~~ Catalooulno~ -~ in Publication Data Pell, Jennifer,1956- Carbonatites, nepheline syenites, kimberlites and relatedrocks in British Columbia (Bulletin, ISSN 0226-7497 ;88) Issued byGeologicalSurveyBranch. 'This is a Contribution to the CanadaIBritisb Columbia Mineral Development Agreement 1985-1990." Indudes bibliographical references: p. ISBN 0-77262170-5 1. Carbonatites -British Columbia. 2. Nepheline Field Research furthis project was caniec! uut syenite -British Columbia. 3. Kimberlite - British durizgtheperiod 1984 to 1990 Columbia. 4. Geology, Economic - British Columbia. 5. Geochemistry - British Columbia, 6.Petrology - British Columbia. I. British Columbia. Ministry of Energy, Mines and Petroleum Resources. 11. British Columbia. GeologicalSurveyBranch. 111. CanadalBritish Columbia Mineral Development Agreement. IV. Title. V. Series: VICTORIA Bulletin (British Columbia. Ministry of Energy, Minesand BRITISH COLUMBIA Petroleum Resources) ; 88. CANADA TN27.B7P44 1994 553.6'09711TN27.B7P44C94-960219-1 1994 July 1994 Ministry of Energx Minesand Petroleum Resources TABLE OF CONTENTS” INTRODUCTION........................................................................ 1 Geochemistry...................................................... 36 Distributiongeneral and characteristics of Geochronology ................................................... 36 carbonatites and nephelinesyenites .................... 2 Distribution and general characteristics of CARBONATITES AND SYENITE GNEISS COMPLliXES IN METAMORPHOSED PRECAMBRIAN EARLY kimberlites and alkaline ultrabasic diatreme TO CAMBRIAN STRATA. OMINECA BELT ............................... 31 breccias ................................................................ 3 Manson Creek area (93N/9) ..................................... 37 Geological work .......................................................... 5 Carbonatites ........................................................ 37 Acknowledgments....................................................... 5 phases 38 Silicate phases ..................................................... Fenites ................................................................. 38 CARBONATITE AND SYENITE COMPLEXES IN Geochemistry ...................................................... 39 PALEOZOIC STRATA, ROCKYAND CASSIAR Geochronology ................................................... 40 MOUNTAINS. FORELANDBELT ............................................ 7 Mount Bisson- Mnnroe Creekarea (93N/9; The Aley Carbonatite complex(94B/5) ...................... 7 930/5. 12).......................................................... 41 Rauhangite core zone............................................ 41 7 rocks Alkalic dike ............................................... Sovite zones........................................................... 7 Pegmatites........................................................... 42 ‘Am phibolitic’ margin ‘Amphibolitic’ ........................................... 7 Intrusive breccias ................................................ 42 Alteration halo ....................................................... 8 Fenites ................................................................. 42 Rare-earth-bearing dikes ..................................... 11 Quartz monzonitesand quartz syenites ..............42 Geochemistry ...................................................... 11 Geochemistry...................................................... 42 Geochronology.................................................... 11 Geochronology ................................................... 43 Wicheeda Lake complex(Prince and George Blue Riverarea (83D/3. 6. 7) ................................... 43 claims, 93V5; 93J/8, 9) 11 ...................................... Carbonatites ........................................................ 44 Carbonatites andassociated syenitic rocks .........13 Nepheline syenites .............................................. 44 Alkaline dikes ...................................................... 13 Mafic Silicate Rocks ........................................... 44 Geochemistry ...................................................... 13 Fenites ................................................................ 47 Geochronology.................................................... 14 Geochemistry ..................................................... 47 BearpawRidge sodalite syenite (93V4).................... 14 Geochronology .................................................. 53 Sodalite syenite ................................................... 15 Trident Mountain (82M/16) .................................... 53 Nonda formationvolcaniclastic rocks ................16 Geochemistry..................................................... 54 Orthogneiss.......................................................... 16 Geochronology .................................................. 54 Postorogenic syenite ........................................... 17 Geochemistry ...................................................... 17 CARBONATITES AND SYENITE GNEISSCOMPLEXES Geochronology.................................................... 18 ASSOCIATED WITH CORE GNEISSES INTHE Oh! INECA Ice River complex (82N/1)....................................... 18 BELT .......................................................................................... 55 Ultramafic series ................................................. 18 Mount Copeland nephelinesyenite gneisses Zoned syenite complex ....................................... 19 (82W2) ............................................................. 55 Carbonatites......................................................... 19 Nepheline syenite gneisses ................................ 55 Lamprophyres ..................................................... 20 Alkaline amphibolite......................................... 58 Geochemistry ...................................................... 22 Grey syenruc.. gneiss ........................................... 58 Geochronology.................................................... 23 Geochemistry ..................................................... 59 Rock Canyon Creekfluorite and rare-earth Geochronology ................................................... 60 element showing(82J13E) ................................. 24 Carbonatites and associated rocks. west flank, Minerahzatlon....................................................... Frenchman Cap 25 dome (82W2, 7, 10) ...............60 Geochemistry ...................................................... 25 Perry River intrusive carbonatites (82Wr)........ 60 Geochronology.................................................... 27 Fenites - Perry River area .................................. 60 Kechika Riverarea (94L/ll, 12, 13) ........................ 27 Ratchford Creek (Ren)intrusive carbona:ite Distribution and field relationships of (82W7) ........................................................ 62 alkaline rocks ............................................... 28 Intrusive syenite - Perry River area Petrography: syenites .......................................... 30 (82W7, 10) .................................................. 62 Petrography: trachytes ......................................... 31 Mount Graceextrusive carbonatite Petrography: (82W7, 10).................................................. 63 feldspar-quartz-carbonate-sericiterocks .....31 Geochemistry ...................................................... 66 Petrography: carbonatites.................................... 34 Geochronology ................................................... 68 _- Bulletin 88 iii Three Valley Gap (82L/16)....................................... 68 Carbonatites and syenite gneisses ........................... 111 Carbonatites, fenites, syenites ............................. 69 Kimberlites. lamprophyres andother ultrabasic Geochemistry....................................................... 70 diatremes.............................................................. 111 Geochronology .................................................... 70 Tectonlc lmphcattons .............................................. 113 ULTRABASIC DIATREMESIN NORTHERN BRITISH REFERENCES ........................................................................ 119 COLUMBIA............................................................................... 71 The Kechika River diatreme andrelated rocks APPENDICES ......................................................................... 125 (94L/12, 13)........................................................ 71 COLOUR PHOTOS ................................................................. 135 Lithology ............................................................. 71 Geochemistry....................................................... 73 FIGURES Geochronology .................................................... 74 1. Index map, carbonatite and syenite gneiss Ospika Pipe(94B/5) .................................................. 74 complexes ..................................................................... 2 Lithology ............................................................