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La suite intrusive de Sept-îles (SISI) est une grande intrusion mafique litée (80km par 5,6 km) associée à l'ouverture de l'océan lapétus (564 Ma) et encaissée dans les gneiss fortement déformés du Grenville. La SISI se compose de 4 intrusions : l'intrusion mafique de Sept-îles (composante majeure), l'intrusion de bordure de Sept-îles, l'intrusion de Pointe du Criard (PdC) et les dykes et filon-couches de gabbro tardifs. Le but de ce projet est de déterminer l'origine des roches felsiques qui sont associées à la SISI. La série supérieure de l'intrusion mafique de Sept-îles ainsi que les composantes felsiques du filon-couche de Pointe du Criard ont donc été analysées. La série supérieure se divise en trois composantes : les quartzo-syénites et syenites à feldspaths alcalins sans enclave, avec enclaves et les zones à coussins. Ces zones à coussins sont caractérisées par la présence de coussins syénitiques sans enclave (50 cm à 5 mètres) entre lesquels il y a un matériel interstitiel syénitique très riche en enclaves. Le filon-couche PdC, qui recoupe la série supérieure, est formé de trois composantes : une bordure figée de diabase et un leucogabbro qui forment environ 2 % du filon-couche alors que les 98% restant sont formés par la syenite porphyrique. Au point de vue minéralogique, la composition des échantillons de la série supérieure et du filon-couche varie très peu et est généralement caractérisée par l'assemblage suivant : feldspath potassique microperthitique + quartz + hornblende (avec parfois des c?urs reliques de clinopyroxène) + oxydes Fe-Ti (magnétite/ilménite) + minéraux accessoires (zircons, titanite,± apatite, biotite). La géochimie des roches de la série supérieure et du filon-couche PdC est relativement semblable et elle indique que tous les échantillons sont des granitoïdes de type-A. Les modélisations de la cristallisation fractionnée effectuées à partir des éléments majeurs et des éléments traces ont permis de déterminer que les 3 composantes de la

This paper reports on a new deposit in the Sept-Iles Complex, with a potential of apatite-ilmenite co-production , with a titaniferous magnetite concentrate a possible by-product. Probable reserves of 107 800 000 tonnes grading 15% apatite and 16% ilmenite or 6.19% P2O5 and 8.41% TiO2 would sustain open-pit mining for 25 years. It is aimed to reduce processing costs by improving the present milling process, which recovers 90% of apatite to a high-grade 40% P2O5 concentrate and also produces a 47% TiO2 concentrate. Magnetite containing 14.5% TiO2 is a possible by-product., This paper reports on a new deposit in the Sept-Iles Complex, with a potential of apatite-ilmenite co-production , with a titaniferous magnetite concentrate a possible by-product. Probable reserves of 107 800 000 tonnes grading 15% apatite and 16% ilmenite or 6.19% P2O5 and 8.41% TiO2 would sustain open-pit mining for 25 years. It is aimed to reduce processing costs by improving the present milling process, which recovers 90% of apatite to a high-grade 40% P2O5 concentrate and also produces a 47% TiO2 concentrate. Magnetite containing 14.5% TiO2 is a possible by-product.

Le Complexe intrusif de Matamec (1.38-1.35 Ga) se situe en Moyenne-Côte-Nord, dans le centre-est de la Province géologique de Grenville au Québec. I1 représente une intrusion mafique-felsique en feuillets d'envergure régionale (80 x 40 km) chevauchée sur les gneiss migmatisés du Complexe de Manitou lors de l'orogénie grenvillienne. Les gabbronorites massifs y dominent et y sont intercalés avec des lambeaux de paragneiss et des feuillets massifs à foliés de mangérites, de monzonites et de granites porphyriques, communément à texture rapakivi. Des zones de mélange de magmas, contenant des enclaves gabbronoritiques microgrenues incluses dans des phases monzonitiques ou monzodioritiques hybrides, sont communes dans le Complexe et reflètent une mise en place contemporaine des magnas mafiques et felsiques. La structure des enclaves comporte tous les intermédiaires entre des enclaves amiboïdes et massives et des enclaves allongées, qui définissent une foliation magmatique et, par endroits, des plis d'écoulement. Certaines enclaves sub-verticales, situées de part et d'autre du Complexe, présentent des critères de polarité à leur base structurale (e.g., empreintes de charge, skuctures de flamme, veines granitiques ascendantese t moulage de phénocristaux), qui témoignent d'une mise en place et d'une cristallisation à l'horizontale des feuillets. Des faciès intermédiaires et hybrides issus d'un mélange entre des magmas mafiques et felsiques affleurent sporadiquement à l'intérieur du Complexe et ont été identifiés comme des monzodiorites quartzifères. Ces roches comportent des xénocristaux de quartz et de feldspath potassique baignant dans une matrice dioritique à grain fin. Les textures de type rapakivi et les mégacristaux de quartz présents dans les monzonites et les monzodiorites, ainsi que la présence de zonations oscillatoires dans les zircons et localement dans le plagioclase, témoignent de conditions d'instabilité lors de la cristallisation de ces magmas. Ces textures se

The layered mafic complex in Quebec, over 80 km in diameter and over 6 km thick, was emplaced within a rift zone related to the opening of the Iapetus Ocean and dated at 544 Ma. It is made up of four series of leucotroctolites, troctolites rich in Fe-Ti oxides, and breccia grading up into diorites, monzonites and leucogranites. The Critical Zone, between the Layered and Transitional series, is made up of magnetite and nelsonite injected by massive olivine gabbro. Within this zone, 108 000 000 tonnes of ore grading 6.25% P2O5 and 8.40% TiO2 have been outlined. The various exposures visited are described., The layered mafic complex in Quebec, over 80 km in diameter and over 6 km thick, was emplaced within a rift zone related to the opening of the Iapetus Ocean and dated at 544 Ma. It is made up of four series of leucotroctolites, troctolites rich in Fe-Ti oxides, and breccia grading up into diorites, monzonites and leucogranites. The Critical Zone, between the Layered and Transitional series, is made up of magnetite and nelsonite injected by massive olivine gabbro. Within this zone, 108 000 000 tonnes of ore grading 6.25% P2O5 and 8.40% TiO2 have been outlined. The various exposures visited are described.

Drilling of the Quebec complex, which was already divided up into a layered, a transitional and an upper series, has provided almost complete information over a thickness of more than 3 km. The Rivieres des Rapides apatite is at the top of the layered series, within a hybrid sequence known as the critical zone, which is made up of the products of quite advanced differentiation injected by massive, fine-grained layers associated with a later magma. The critical zone consists of a 30 m subzone made up of titaniferous magnetite layers around 1 m thick, a 10 m layered nelsonite subzone, a 150 m cyclic subzone of olivine, pyroxene and plagioclase cumulates in a nelsonitic intercumulus phase, and a 30-50 m microtroctolite subzone. The first three subzones have been injected by massive olivine leucogabbro poor in Fe-Ti oxides and apatite. Within the critical zone, Ca and Mg contents vary rapidly, while Cr in the injected gabbro distinguishes it from the cumulates. The appearance of an immiscible nelsonitic liquid appears to have been linked with the injection of a new magma into a residual magma rich in incompatible elements such as P., Drilling of the Quebec complex, which was already divided up into a layered, a transitional and an upper series, has provided almost complete information over a thickness of more than 3 km. The Rivieres des Rapides apatite is at the top of the layered series, within a hybrid sequence known as the critical zone, which is made up of the products of quite advanced differentiation injected by massive, fine-grained layers associated with a later magma. The critical zone consists of a 30 m subzone made up of titaniferous magnetite layers around 1 m thick, a 10 m layered nelsonite subzone, a 150 m cyclic subzone of olivine, pyroxene and plagioclase cumulates in a nelsonitic intercumulus phase, and a 30-50 m microtroctolite subzone. The first three subzones have been injected by massive olivine leucogabbro poor in Fe-Ti oxides and apatite. Within the critical zone, Ca and Mg contents vary rapidly, while Cr in the injected gabbro distinguishes it from the cumulates. The appearance of an immiscible nelsonitic liquid appears to have been linked with the injection of a new magma into a residual magma rich in incompatible elements such as P.

The deposit, in Quebec, consists of a nelsonite (apatite-ilmenite-magnetite) unit in a layered mafic complex. A number of parallel apatite-ilmenite ore zones consist of nelsonite-enriched troctolites and olivine gabbros, interspersed with similar rocks in which less nelsonite precipitated with the silicates. Marketable concentrates of apatite and ilmenite, grading 40% P2O5 and 47% TiO2 respectively, have been prepared in pilot-plant testing, as well as a titanomagnetite concentrate of 4.7 g/cm3 density, grading 81.6% Fe2O3, which could be marketed as a heavy medium for mineral separation. The location near a major year-round port allows the possibility of selling waste gabbro as aggregate, while another potential commodity is vanadium from low grades (0.54% V2O5) in the titanomagnetite and olivine. Probable reserves have been estimated as 107 800 000 t averaging 6.2% P2O5 and 8.4% TiO2; the waste:ore ratio is 1.13:1 and capital costs estimated for mine and mill total Can, The deposit, in Quebec, consists of a nelsonite (apatite-ilmenite-magnetite) unit in a layered mafic complex. A number of parallel apatite-ilmenite ore zones consist of nelsonite-enriched troctolites and olivine gabbros, interspersed with similar rocks in which less nelsonite precipitated with the silicates. Marketable concentrates of apatite and ilmenite, grading 40% P2O5 and 47% TiO2 respectively, have been prepared in pilot-plant testing, as well as a titanomagnetite concentrate of 4.7 g/cm3 density, grading 81.6% Fe2O3, which could be marketed as a heavy medium for mineral separation. The location near a major year-round port allows the possibility of selling waste gabbro as aggregate, while another potential commodity is vanadium from low grades (0.54% V2O5) in the titanomagnetite and olivine. Probable reserves have been estimated as 107 800 000 t averaging 6.2% P2O5 and 8.4% TiO2; the waste:ore ratio is 1.13:1 and capital costs estimated for mine and mill total Can

The Sept-Iles concentrator grinds the ore to liberate the iron minerals from the silica gangue, and carries out flotation to concentrate the iron. The iron concentrate slurry is pumped to the pellet plant where it is thickened, filtered and dried to prepare it for agglomeration into pellets. Improvements and modifications were made to the mill discharge grate, the shell liner configurations in the primary grinding mills, and a secondary grinding circuit was installed in each primary grinding circuit., The Sept-Iles concentrator grinds the ore to liberate the iron minerals from the silica gangue, and carries out flotation to concentrate the iron. The iron concentrate slurry is pumped to the pellet plant where it is thickened, filtered and dried to prepare it for agglomeration into pellets. Improvements and modifications were made to the mill discharge grate, the shell liner configurations in the primary grinding mills, and a secondary grinding circuit was installed in each primary grinding circuit.

Following grinding and flotation, the iron concentrate slurry is pumped to the pellet plant where it is further processed by thickening, filtering, and drying to prepare it for agglomeration into pellets. Descriptions of the grinding and flotation circuits are given as are details of the design and production of the concentrator. The concentrator was designed to produce a concentrate grade of 63.1% Fe and 3.5% SiO. but has not yet reached this goal, producing 63.7% Fe and 4.7% SiO. in 1979., Following grinding and flotation, the iron concentrate slurry is pumped to the pellet plant where it is further processed by thickening, filtering, and drying to prepare it for agglomeration into pellets. Descriptions of the grinding and flotation circuits are given as are details of the design and production of the concentrator. The concentrator was designed to produce a concentrate grade of 63.1% Fe and 3.5% SiO. but has not yet reached this goal, producing 63.7% Fe and 4.7% SiO. in 1979.

Following identification of an apatite, ilmenite and magnetite deposit, in-situ geological resources of 200 000 000 t were indicated by drilling and mineable reserves of 108 000 000 t grading 6.2% P2O5 and 8.4% TiO2 were delineated. The project is ideally located near a large, well established mining community and has good access by sea, road and rail. Technical aspects achieved during the feasibility study were: development of an efficient, clean process flowsheet for both phosphate and igneous ilmenite concentrates; harmonisation of mining and milling facilities with existing activities; and the production of very high-quality concentrates capable of competing on world markets and satisfying stringent requirements. Capital and operating costs are estimated as attractive for vertically integrated concentrate end-users., Following identification of an apatite, ilmenite and magnetite deposit, in-situ geological resources of 200 000 000 t were indicated by drilling and mineable reserves of 108 000 000 t grading 6.2% P2O5 and 8.4% TiO2 were delineated. The project is ideally located near a large, well established mining community and has good access by sea, road and rail. Technical aspects achieved during the feasibility study were: development of an efficient, clean process flowsheet for both phosphate and igneous ilmenite concentrates; harmonisation of mining and milling facilities with existing activities; and the production of very high-quality concentrates capable of competing on world markets and satisfying stringent requirements. Capital and operating costs are estimated as attractive for vertically integrated concentrate end-users.

The gently dipping apatite units, up to 175 m thick, include 107 800 000 t grading 15% apatite and 16% ilmenite. The complex is a circular intrusion, 80 km in diameter, reflecting three major Cambrian magmatic cycles. The first cycle is divided into the Lower Series of unlayered troctolites and the 3 km thick Layered Series of troctolites, olivine gabbros and gabbros, containing more than 15% Fe-Ti oxides and terminating in the 250 m thick Critical Zone that hosts the deposits. The rocks of the 10 m Nelsonite Subzone contain more than 90% Fe-Ti oxides and apatite, the latter exceeding 25 wt%. The 150 m Gabbro-Nelsonite Subzone has more than 50% nelsonite in its lower half, while the proportion of silicates increases upwards. Fractionation of the nelsonites could have been favoured by enrichment of the parent magmas in Fe, Ti and P before their final emplacement. Production is projected at 4 000 000 t/a by open pit, yielding 600 000 t/a apatite and 330 000 t/a ilmenite concentrates., The gently dipping apatite units, up to 175 m thick, include 107 800 000 t grading 15% apatite and 16% ilmenite. The complex is a circular intrusion, 80 km in diameter, reflecting three major Cambrian magmatic cycles. The first cycle is divided into the Lower Series of unlayered troctolites and the 3 km thick Layered Series of troctolites, olivine gabbros and gabbros, containing more than 15% Fe-Ti oxides and terminating in the 250 m thick Critical Zone that hosts the deposits. The rocks of the 10 m Nelsonite Subzone contain more than 90% Fe-Ti oxides and apatite, the latter exceeding 25 wt%. The 150 m Gabbro-Nelsonite Subzone has more than 50% nelsonite in its lower half, while the proportion of silicates increases upwards. Fractionation of the nelsonites could have been favoured by enrichment of the parent magmas in Fe, Ti and P before their final emplacement. Production is projected at 4 000 000 t/a by open pit, yielding 600 000 t/a apatite and 330 000 t/a ilmenite concentrates.

SOQUEM and Norsk Hydro have defined a deposit of apatite, ilmenite and magnetite within the Sept-Iles layered mafic complex, Quebec. Marketable concentrates of apatite and ilmenite have been prepared in pilot plant tests. The apatite concentrate grades 40% P2O5; the ilmenite concentrate 47% TiO2. Apatite is used in the production of NPK-type fertilizers; the ilmenite is a sulphatable grade feedstock for the TiO2 pigment industry. A titanomagnetite concentrate of density 4.7 g/cm3 and grading 81.6% Fe2O3 has also been prepared. This product could be marketed as heavy media for mineral separation. Waste gabbro could be sold as aggregate. Other potential commodities are vanadium from the titanomagnetite and olivine. A probable reserve of 108 000 000 t at an average grade of 6.2% P2O5 and 8.4% TiO2 has been identified. The waste:ore ratio is 1.13:1. The capital costs for mine and mill total Can, SOQUEM and Norsk Hydro have defined a deposit of apatite, ilmenite and magnetite within the Sept-Iles layered mafic complex, Quebec. Marketable concentrates of apatite and ilmenite have been prepared in pilot plant tests. The apatite concentrate grades 40% P2O5; the ilmenite concentrate 47% TiO2. Apatite is used in the production of NPK-type fertilizers; the ilmenite is a sulphatable grade feedstock for the TiO2 pigment industry. A titanomagnetite concentrate of density 4.7 g/cm3 and grading 81.6% Fe2O3 has also been prepared. This product could be marketed as heavy media for mineral separation. Waste gabbro could be sold as aggregate. Other potential commodities are vanadium from the titanomagnetite and olivine. A probable reserve of 108 000 000 t at an average grade of 6.2% P2O5 and 8.4% TiO2 has been identified. The waste:ore ratio is 1.13:1. The capital costs for mine and mill total Can

The Iron Ore Company of Canada (IOC) operates a mining, concentrating and pelletising complex in Labrador City, Newfoundland, with railway and shipping facilities at Sept-Iles, Quebec. The Carol Mining and Concentrating division of IOC is exploring opportunities to apply technology to support improved business results. Their Vision 2000 maintenance integration plan has evolved from the concept of acquiring machine or equipment condition information through radio transmission and computer interface technology. Through remote instrumentation, details of the condition of a piece of equipment can be transmitted to a central dispatch database where it can be interfaced with a maintenance expert system. The maintenance plan is built on the mine's truck dispatch system, which also serves as the common database for all transmitted data including equipment hours and vital signs monitoring alarms., The Iron Ore Company of Canada (IOC) operates a mining, concentrating and pelletising complex in Labrador City, Newfoundland, with railway and shipping facilities at Sept-Iles, Quebec. The Carol Mining and Concentrating division of IOC is exploring opportunities to apply technology to support improved business results. Their Vision 2000 maintenance integration plan has evolved from the concept of acquiring machine or equipment condition information through radio transmission and computer interface technology. Through remote instrumentation, details of the condition of a piece of equipment can be transmitted to a central dispatch database where it can be interfaced with a maintenance expert system. The maintenance plan is built on the mine's truck dispatch system, which also serves as the common database for all transmitted data including equipment hours and vital signs monitoring alarms.

The cost reduction programme implemented by the Iron Ore Company of Canada in 1981-86 in the face of recession in the iron ore market is described. The first phase included closure of mining operations at Schefferville, mothballing the concentrator and pellet plant at Sept-Iles and a 40% reduction in operations at the Carol Project. Organisational infrastructure was cut back or eliminated and long-term supply contracts renegotiated. In the second phase, emphasis was given to economies in the larger cost items and the final phase involves fine tuning of the operations as a whole to reduce costs still further., The cost reduction programme implemented by the Iron Ore Company of Canada in 1981-86 in the face of recession in the iron ore market is described. The first phase included closure of mining operations at Schefferville, mothballing the concentrator and pellet plant at Sept-Iles and a 40% reduction in operations at the Carol Project. Organisational infrastructure was cut back or eliminated and long-term supply contracts renegotiated. In the second phase, emphasis was given to economies in the larger cost items and the final phase involves fine tuning of the operations as a whole to reduce costs still further.