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The development of robust 3-D geological models involves the integration of large amounts of public geological data, as well as additional accessible proprietary lithological, structural, geochemical, geophysical, and diamond drill hole data. 3-D models and maps have been available, particularly in the petroleum industry, for more than 10 years. Here, we demonstrate how robust 3-D maps can be used as interactive tools for mineral deposits exploration. In particular, we show how the interrogation of 3-D data sets can constrain exploration targets at depth. The main advantages of this technique for the mining industry are the homogeneity of data treatment and the validation of geological interpretations, taking into account geophysical and geochemical data. Data integration and cross-correlation of geology and geophysics can be achieved in two dimensions in any good GIS package. However, the added strength of 3-D analysis is the integration of separate data sets in three dimensions to build more complete, more realistic models, and in delineating areas of high economic potential at depth. Furthermore, these models can be modified and improved at any time by adding new data from ongoing drilling and geoscientific surveys. This paper presents two examples of 3-D models used for mineral exploration: the Joutel VMS mining camp and the Duparquet gold camp, Quebec. In both examples, the creation of the model is discussed and queries specific to the relevant exploration model are introduced. Eight potential exploration targets are generated at Joutel and seven at Duparquet. Although the targets defined are dependent on the details of the chosen queries, it is apparent that this technique has the potential to generate promising exploration activity that can engender new targets.

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At the Jubilee deposit, the host Macumber Formation consists of four successive lithofacies: micritic, intramicritic, sheared and brecciated. The Pb-Zn ore minerals are always restricted to this last brecciated unit which contains fragments of sheared limestones. We interpret the sheared limestones as calcmylonite and suggest that progressive shearing resulted in brecciation of this calcmylonite. Preliminary ë18O-ë13C results for the carbonate units and paragenetic phases from the mine area indicate that micritic limestones were stabilized under warm, burial conditions. A biogenic carbon-rich system has influenced recrystallization of limestones during shearing, and has precipitated pre-, syn- and post-ore calcites. The Ainslie Detachment probably provided the necessary background preparation for Pb-Zn mineralization at the deposit, by creating secondary porosity through brecciation and new channelways through faulting.

The Macumber Formation, a finely laminated limestone consisting of two thin units, represents a key strati graphic marker at the base o f the Visean Windsor Group. On Cape Breton Island the formation hosts numerous PbZn occurrences, and its upper boundary is in contact with rocks ranging in age from Visean (early Carboniferous) to Westphalian (middle Carboniferous), the origin o f the stratigraphic omissions being debatable.This first inorganic diagenesis study identifies nine post-depositional processes, including the stabilization of marine components, and evaporite and anhedral calcite precipitation. The (-13.0 to 2.0%o), 87Sr/86Sr (0.7076 to 0.7079) and [Sr] (50 to 10000 ppm) of samples, including upper and basal whole-rock units and anhedral calcite cements, show two trends enveloping the entire field of data. The trends suggest that an evaporite-derived, non-radiogenic fluid and a clastic-derived radiogenic fluid mixed and interacted with the limestone sediments, in a progressively deeper burial environment. The evaporite-derived fluid mostly imprinted the top unit o f the for mation. The field investigations, microscope observations and geochemical results do not indicate a meteoric overprint as would be expected if an unconformity existed along the top o f the formation. The burial history documented here, and the presence of fibrous calcite indicating bedding parallel shearing, support a detachment model to explain the stratigraphic omissions within the Windsor Group.La Formation de Macumber, composee de calcaires fins en deux minces unites, represente un marqueur stratigraphique crucial k la base du Groupe de Windsor. A Pile du Cap Breton, la formation encaisse plusieurs indices Pb-Zn et constitue la limite inferieure d'une serie d'omissions stratigraphiques k l'interieur du Groupe de Windsor, l'origine desquelles est fortement d6battue.Cette premiere investigation de la diagenese inorganique place neuf processus en une succession post-ddpositionnelle incluant la stabilisation des elements marins, et la precipitation d 'evaporites et de ciments calcitiques anddriques. Les 5 18OpD3 (-13.0 to 2.0%o), 87Sr/86Sr (0.7076 to 0.7079) et [Sr] (50 to 10000 ppm) de micro£chantillons des unites inferieures et superieures, et de ciments anedriques montrent deux tendences enveloppant l'ensemble des rdsultats. Ces tendences suggerent qu'un fluide non-radiogenique, evaporitique et un fluide radiogenique derive de roches clastiques, auraient affecte les sediments calcaires au cours de leur enfouissement progressif plus profond. Le fluide evaporitique aurait principalement affecte I'unite superieure de la formation. Les donnees de terrain, les observation microscopiques et les resultats geochimiques n'indiquent pas l'empreinte m6teorique attendue si une discordance existait au sommet de la formation. L'histoire diag6netique ici documentee, ainsi que Pexistence de calcite fibreuse ddveloppde le long de plans de cisaillement paralieies au litage supportent le modeie de detachement pour expliquer les omissions stratigra...