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TitreExploration geophysics for intrusion-hosted rare earth metals / Géophysique d'exploration pour les métaux rares associés à des intrusions
AuteurThomas, M D; Ford, K L; Keating, P
SourceCommission géologique du Canada, Dossier public 6828, 2011, 1 feuille, (Accès ouvert)
ÉditeurRessources naturelles Canada
RéunionAME BC Mineral Exploration Roundup 2011; Vancouver; CA; janvier 24th-27th, 2011
Documentdossier public
Mediapapier; en ligne; numérique
Formatspdf; JPEG2000
Sujetslevés géophysiques; interprétations géophysiques; interprétations magnétiques; interprétations radiométriques; levés magnétiques; levés radiométriques; anomalies; terres rares; gîtes minéralogiques; intrusions; complexes de carbonatite alcaline; complexes carbonatitiques; pegmatites; Complexe d'Oka Alkaline ; Complexe de Misery Lake Alkalic Intrusive ; Complexe de Strange Lake Alkalic Intrusive ; Complexe de Mutton Bay ; géologie économique; géophysique
Illustrationslocation maps; tables; geophysical images; geophysical profiles
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)
Bibliothèque de Ressources naturelles Canada - Québec (Sciences de la Terre)
ProgrammeÉtude des gîtes des métaux rares, Initiative géoscientifique ciblée (IGC-4)
Diffusé2011 03 18
Résumé(disponible en anglais seulement)
Intrusion-related deposits of rare earth metals are characteristically associated with alkaline and carbonatitic intrusions, pegmatites and intrusive veins. Historically, intrusion-related rare earth metals have been discovered using a variety of exploration techniques and occasionally by chance. Geophysical methods have featured prominently. Here we present examples of geophysical signatures and case histories. Critical to the success of any geophysical method is the presence of a sufficiently large contrast in the rock properties of the investigated geological units. Rock properties of 28 minerals that may contain rare earth elements (REEs) in economic or potentially economic deposits (Castor and Hedrick, 2006) are indicated in the figure to the left. Properties are mainly from the Mineralogical Society of America (2010). Noticeable are the high densities of practically all of the minerals, with a 3 general range of 3.26 - 5.90 g/cm , significantly higher than that of common 3 crustal rocks 2.60 - 3.30 g/cm . Notable also are the facts that many minerals are radioactive, and practically all are non-magnetic. Based on these properties it seems that the gravity and radiometric techniques have the greatest potential for direct detection of REEs, but it must be recognized that such direct detection is very much dependant on the concentration of these minerals and the size of the deposit. It would appear, more commonly, that detection of rare earth metals, like detection of several other commodities, is achieved by first locating a prospective host for the mineralization. In this respect, as will be demonstrated following, the gravity, magnetic and radiometric techniques are all important exploration tools.