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TitreKimberlite indicator mineral chemistry of the Bucke and Gravel kimberlites and associated indicator minerals in till, Lake Timiskaming, Ontario
AuteurMcClenaghan, M B; Kjarsgaard, I M; Kjarsgaard, B A
SourceCommission géologique du Canada, Dossier public 5815, 2012, 30 pages; 1 CD-ROM,
Documentdossier public
MediaCD-ROM; numérique; en ligne
Formatsrtf; xls; pdf
Lat/Long OENS-79.7833 -79.6000 47.5000 47.3667
Sujetséléments d'indice; exploration de dépôts glaciaires; géochimie des dépôts glaciaires; profils de dispersion; diamant; kimberlites; prospection minière; dépôts glaciaires; tills; géochimie du till; lithologie; pyrope; ilménite; olivine; grenat; diopside; chromite; enstatite; directions du transport de la glace; directions des mouvements de la glace; Kimberlite de Gravel ; géologie économique; géochimie; géologie des dépôts meubles/géomorphologie; Mésozoïque; Jurassique
Illustrationslocation maps; plots; tables
Ontario Geological Survey
Ontario Geological Survey, John B. Gammon Geoscience Library, Sudbury
Bibliothèque de Ressources naturelles Canada - Ottawa (Sciences de la Terre)
Bibliothèque de Ressources naturelles Canada - Calgary (Sciences de la Terre)
Commission géologique du Canada (Atlantique)
Bibliothèque de Ressources naturelles Canada - Vancouver (Sciences de la Terre)
ProgrammeL'Initiative géoscientifique ciblée (IGC-1), 2000-2003
LiensCanadian Database of Geochemical Surveys, downloadable files
LiensBanque de données de levés géochimiques du Canada, fichiers téléchargeables
Diffusé2012 02 02; 2012 03 06
Résumé(disponible en anglais seulement)
A well documented glacial dispersal fan of kimberlite indicator minerals extends southward from the region of the Late Jurassic Bucke and Gravel kimberlites in the Lake Timiskaming kimberlite field of northeastern Ontario. The Geological Survey of Canada collected and analyzed a sample of kimberlite from both pipes and re-examined and analyzed indicator minerals from archived heavy mineral concentrates of till samples from the dispersal fan. The Bucke kimberlite contains more than 30,000 indicator mineral grains per 10 kg sample in the 0.25 to 0.5 mm fraction, which consists of, in decreasing order of abundance, Crpyrope>> Mg-ilmenite>chromite>Cr-diopside. The Gravel kimberlite is three times as indicator mineral rich, containing more than 100,000 grains per 10 kg sample in the 0.25 to 0.5 mm fraction, which consist of Mg-ilmenite>>Cr-pyrope>chromite>Cr-diopside. No olivine was recovered from either sample. Till samples within the fan contain 100s to 1000s of indicator minerals per 10 kg sample, mostly Mg-ilmenite, with Cr-pyrope and chromite, and lesser amounts of Cr-diopside and minor olivine. Indicator minerals are most abundant to the southwest to southeast of the two kimberlites and form a fan-shaped dispersal pattern that extends at least 6 km, and potentially 30 km down-ice. The results presented here demonstrate how ice-flow mapping can be combined with indicator mineral abundance, mineral chemistry, and relative abundance data to define dispersal patterns from kimberlite.