 | | Journal (article/letter/editorial) | | genesis and evidence for melts from intrusive chromitite formation in the Mackenzie large igneous province...T6G 2E3, Canada Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario K1A 0E8, Canada a r t i...isotopes Mackenzie large igneous province Coppermine River Assimilation and fractional crystallization...c t The 1.27 Ga Coppermine continental flood basalt (CFB) province in northern Canada represents the extrusive...includes the Mackenzie dyke swarm and the Muskox layered intrusion. New Re–Os isotope and highly siderophile |  | | Journal (article/letter/editorial) | | origin of marginal rocks from the Muskox layered intrusion (Nunavut, Canada) and implications for the evolution...Columbia, Vancouver, B.C., V6T 1Z4, Canada Anglo American Exploration (Canada) Ltd., 800-700 West Pender Street...Street, Vancouver, B.C., V6C 1G8, Canada a r t i c l e i n f o Article history: Received 19 May 2008...isotopes U–Pb geochronology Muskox intrusion Marginal zone Coppermine River flood basalts Mackenzie large...province a b s t r a c t The Muskox mafic–ultramafic layered intrusion, Nunavut, is part of the widespread |  | | Journal (article/letter/editorial) | | sequences in the Muskox intrusion and other layered intrusions-II. Origin of chromitite layers and similar...occasions when the basic parental magma of the intrusion is suddenly extensively contaminated with granitic...differentiation patterns of Cr and Wi in the Muskox intrusion. The granitic melt is produced because most...most of the crystals formed in the intrusion accumulate on its floor, leaving the roof rocks to be continuously...density and high viscosity. granophyre. In the Muskox intrusion there are two chromite-rich layers, each occurring |  | | Journal (article/letter/editorial) | | Gefiige der Chromitite mit denen sedimentiirer Gesteine wird geschlossen, dab die Chromitite dutch gravitative...Orissa. The layers occur all intrusion (WAGER, 1968), Muskox intrusion (SMITH and KaPr 1963), Duke Island...Orissa, India 281 Fig. 1. Thinnly laminated chromitite from Sukinda Valley, Cuttack district, Orissa...is 25 feet thick Fig. 2. A thinnly laminated chromitite layer is moulded around a kernel of altered ultrabasic...bottom of the layer. The pen is placed on the chromitite Nature of the Primary Structures The p r i m |  | | Journal (article/letter/editorial) | | 00 Petrology of the G and H Chromitite Zones in the Mountain View Area of the Stillwater Complex, Montana...University of Toronto, Mississauga, Ontario L5L 1C6, Canada (Received 19 August 1990; revised typescript accepted...Stillwater Complex in the Mountain View area of the intrusion consists of 17 cyclic units that have been...near their base, the thickest being the G and H chromitite zones in units 10 and 11. The G and H zones are...pegmatite; and they are both succeeded by thinner chromitite zones, respectively called the hanging wall G |  | | Journal (article/letter/editorial) | | Mesoproterozoic stratigraphic successions of northern Canada R.H. Rainbird a,∗ , A.D. Rooney b , R.A. Creaser...Geological Survey of Canada, Natural Resources Canada, Ottawa, ON K1A 0E8, Canada Department of Earth... University of Alberta, Edmonton, AB, T6G 2E3, Canada a r t i c l e i n f o Article history: Received...Mesoproterozoic stratigraphic successions within northern Canada. Shale from the basal Escape Rapids Formation yields...northward-dipping section exposed along the Coppermine River, which drains Canada’s central-northern mainland |  | | Journal (article/letter/editorial) | | palladium in ultramafic rocks of the Bird River Sill, SE Manitoba, Canada P. Theyer Manitoba Energy and Mines...Mines, 555-330 Graham Avenue, Winnipeg, Manitoba, Canada, R3C 4E3 Received: March 2, 1989/Revisedversion:...portion of the Archean Bird River Sill, a mafic-ultramafic stratiform intrusion in southeastern Manitoba...olivine crystals hosting PGE enriched layers and chromitite layers near its stratigraphic top. The contrasting...mechanisms and crystallization histories. The Bird River Sill in southeastern Manitoba is a differentiated |  | | Journal (article/letter/editorial) | | pp. 895–907 AGE OF THE BIRD RIVER SILL, SOUTHEASTERN MANITOBA, CANADA, WITH IMPLICATIONS FOR THE SECULAR...SECULAR VARIATION OF LAYERED INTRUSION-HOSTED STRATIFORM CHROMITE MINERALIZATION JAMES S. SCOATES1,† AND...V6T-1Z4, Canada 2 2502 Holyrood Drive, Nanaimo, BC V9S-4K9, Canada Abstract The Archean Bird River sill...mafic-ultramafic layered intrusion in the Bird River greenstone belt of southeastern Manitoba, Canada, contains significant...concentrations of platinum group elements. Stratiform chromitite, displaying both remarkable lateral continuity |  | | Journal (article/letter/editorial) | | chromitites and peridotites from the Stillwater, Muskox and Rum layered intrusions, we show that radiogenic...Igneous Complex, −0.05 to 0.17 for the ∼1.27 Ga Muskox Intrusion, and 0.02 to 0.13 for the ∼0.06 Ga Rum Layered...observations are consistent with published models for chromitite genesis that invoke either crustal melt-primitive...demonstrate the importance of this process for chromitite seams from layered intrusions of differing ages...(2.7 Ga Stillwater Igneous Complex; 1.27 Ga Muskox Intrusion; 0.060 Ga Rum Igneous Complex) and discuss |  | | Journal (article/letter/editorial) | | fractionation representedin the Lower Zone of the Olifants River trough and is not the product of a separate, later...256 KT, Mooi- Complexextendsfrom the Olifants River to the hoek 255 KT, Onverwacht292 KT, and Zeekoegat...Rietfontem Richmond 38. Thorncliffe 39. Helena River KT 372 KT 373 375 KT 370 KT 374 KT C:•JT...sectorof the Eastern BushveldComplex (Fig. 1), the area discussedin the presentpaper. Hall describedrock...the generalgeol- Smith (1967, 1969) for the Muskox intrusion, was ogy of the Critical Zone in the northernpart |  | | Journal (article/letter/editorial) | | units. Applications to the Skaergaard, Bushveld, Muskox, Stillwater, and other intrusions are briefly described...cumulates was the Layered Series of the Skaergaard Intrusion, and the type cumulus mineral was the dominant...conclusions about plagioclase in the Kiglapait Intrusion). For this reason, the concept of cumulates and... b), and in a recent paper on the Skaergaard Intrusion, McBirney & Noyes (1979, p. 503—4) chose to avoid...megacyclic unit, microcyclic unit Applications Muskox, Great Dyke, Stillwater, Bushveld Slcaergaard, |  | | Journal (article/letter/editorial) | | through the Lower, Critical and Main Zones of the intrusion at Union Section, north-western Bushveld Complex...larger crustal component in the upper part of the intrusion. In contrast, the concentrations of many highly...largest layered ma®c±ultrama®c intrusion, with a subsurface outcrop area of 60,000 km2. It is also the...and Upper Critical Zones host up to 13 massive chromitite layers of up to 1.6 m in thickness (Fig. 2)....clinopyroxene in the ultrama®c portions of the intrusion has been linked to the assimilation of siliceous |  | | Journal (article/letter/editorial) | | 80 60 40 20 0 SECTION MOUNTAIN VIEW ' METERS FEET AREA THICKNESS. 0T° IN FEET (a) Bronzite ^ cumulate...FORMATION IN STILLWATER COMPLEX (b) 957 MOUNTAIN VIEW AREA * ubcr» FEET K METERS -0 EXPLANATION OC' be...cumulus minerals in cyclic unit 2 in the Mountain View area of the Stillwater Complex. Modified after Jackson...section of the cyclic units in the Mountain View area after Jackson (1968). Downloaded from http://petrology...Peridotite zone is ~ 1250 m thick in the Mountain View area. If that thickness represents ~ 5 % fractional crystallization |  | Rivalenti, G., Garuti, G., Rossi, A., Slena, F., Sinigoi, S. (1981) Chromian spinel in the Ivrea-Verbano layered igneous complex, western Alps, Italy. TMPM Tschermaks Mineralogische und Petrographische Mitteilungen, 29 (1). 33-53 doi:10.1007/bf01082813 | Journal (article/letter/editorial) | | therefore, to be the geotectonic environment of intrusion. Zusammenfassung Chrom-Spinell im geschichteten...der bei relativ0hohem Druck (8 kbar) erfolgten Intrusion, zuriickzufNaren ist. 3 TMPM29/1 0 0 4 1 - 3 7...Chromerzlagerst/itten ist also das geotektonische Milieu der Intrusion. Introduction The Ivrea-Verbano Complex, belonging...recognized as a deep-seated, possibly multiple, intrusion (Rivalenti et al., 1975; Rivalenti et al., 1980;...274 ppm at Stiliwater (Hess, 1960); 547 ppm at Muskox (Smith and Kapp, 1963). This suggests that primitive |  | | Journal (article/letter/editorial) | | bodiesof ilmenitein chromite in chromititesfrom Dwars River (Fig. l) and from the M unit (Fig. 2) on Winterveld417...Frischgewoogd 362 KT 33. Kolkfontein 367 KT 34, Dwors River 372 KT 35. Dc Grooteboom 373 KT 36 Rietfontein 375...rutile (white) at margins of chromite grains. Chromitite in Merensky Reef, Umkoanes Stad. (D) Rutile (white)...junctions of chromite grains (gray). Steelpoort chromitite, Jagdlust. and prismatic inclusionsis clearcut...(light gray) and bronzite (medium gray). Base of F chromitite, Annex Grootboom. (C) Rutile crystal (light gray) |  | | Journal (article/letter/editorial) | | Geoscience Studies, Carleton University, Ottawa, Canada Platinum-Group Minerals and Other Solid Inclusions... ~< 20 ~ 5 British Columbia 1) Murray Ridge chromitite in dunite and harzburgite 290 R. W. Talkington...harzburgite a) native silver b) magnetite c) silicate chromitite a) sulphide (1) pyrite b) fluid inclusions c)...Shetland Isles chromitite et al. (1981) New Caledonia 1) Massif du Sud chromitite 2) Massif de Ti61~aghi...Ti61~aghi chromitite a) rutheniridosmine a) laurite b) (Cu, Ni) (Ir, Rh)2 Ss 19 TMPM 32/4 L e g e n |  | | Journal (article/letter/editorial) | | Platinum-Group-Mineral Inclusions in Chromite from the Bird River Sill, Manitoba* W. Talkington**, D. H. Watkinson...Geology, Carleton University, Ottawa, Ontario, Canada K1S 5B6 Platinum-group minerals (PGM) have been...identified as inclusions in chromite from the Bird River Sill, Manitoba. The inclusions are small (< 20 microns)...08240, USA 1981; Newfoundland ophiolitic rocks, Canada, Watkinson and Talkington 1980; Talkington 1981)...here for PGM inclusions in chromite from the Bird River Sill, Manitoba (Trueman 1971) are part of an ongoing |  | | Journal (article/letter/editorial) | | Cuprostibite and associated minerals from the llimaussaq intrusion, South Greenland, 1978 by S. Karup-Møller. L....00 No. 127 The ore minerals of the IUmaussaq intrusion: their mode of occurrence and their conditions...Iratigraphy and vegetalion history in the Scoresb) Sund area. East Greenland. 1978 by S. Funder. D.kr. 95.00...study of differentiation of this type of Archaean intrusion. The igneous crystallization pattern is complicated...stratigraphy, structure, and whole rock chemistry of the intrusion (Windley et al., 1973). Part II reported the results |  | | Journal (article/letter/editorial) | | length of 25 kin. The ultramafic rocks and the chromitite layers are cofolded with the Iron-Ore Supergroup...different varieties of chromite ore present in the area are massive, banded and spotted, laminated and friable...increase with respect to Cr 3+ and Mg2+ in the upper chromitite layers. TiO2 lacks significant correlation with...chromitites and the associated ultramafic rocks of the area was made by Chatterjee and Banerjee (1964) and Banerjee...1). Both the foot wall and hanging wall of the chromitite layers, lenses and pockets are sharply defined |  | | Journal (article/letter/editorial) | | doi:10.1093/petrology/egl069 Origin of the UG2 chromitite layer, Bushveld Complex SISIR K. MONDAL AND EDMOND...ADVANCE ACCESS PUBLICATION NOVEMBER 29, 2006 Chromitite layers are common in large mafic layered intrusions...this and other genetic hypotheses to explain the chromitite layers of the Bushveld Complex, we have conducted...immediately above and below the UG2 chromitite and another chromitite layer lower in the stratigraphic section...at the top of the Lower Critical Zone. The UG2 chromitite is well known because it is enriched in the platinum-group |  | | Journal (article/letter/editorial) | | podiform chromitite from the northern Oman ophiolite as the stratigraphically shallowest chromitite in ophiolite...Springer-Verlag 2004 Abstract A new type of podiform chromitite was found at Wadi Hilti in the northern Oman...the sheeted dike complex and upper gabbro. This chromitite forms small (<30 cm in thickness) pods with irregular...graded bedding is observed within the pods. The chromitite is in the upper crust, by far shallower in ophiolite...by the melting of gabbro blocks. The podiform chromitite reported here is strikingly similar in petrography |  | | Journal (article/letter/editorial) | | chromitites C. F. Ferreira Filho* and S. M. Araujo Chromitite layers in mafic-ultramafic layered intrusions...mineral. Different mechanisms for the formation of chromitite layers have been postulated. In order to provide...Complex (2?2 Ga) is a large layered intrusion of the Amazon Craton. Chromitite layers of the Bacuri mafic-ultramafic...concentrated in a several metresthick chromitite layer (the main chromitite) located at the base of the ultramafic...sequence. The stratigraphic position of the main chromitite supports a model for its origin associated with |  | | Journal (article/letter/editorial) | | gabbrosampleand•3 to 81 ppb in the other 29 samAlong the Indus River valley, the Main Mantle pies,which are mostlychromitites...(Jan,1988). out over an area of about 10,000 km2 and are the In the Indus River valley, the uppermostof...inferred cumulus arrival arrival ß Jijal village • river .------. stream •. igneous layering igneousfoliation...relict igneousmodal layering.The top of the third intrusion,the Patan Complex(Fig. 1), is a spectacular,intrusive...unzonedandtypicallynonsequencecontainingthin chromitite seams,that has poikiliticandeuhedralor subhedral |  | | Journal (article/letter/editorial) | | describedby- Kouvo et al (1963) and from the Muskox intrusion in Canada by Chamberlain and Delabio (1965). During...properties given for the same mineral from the Muskox intrusion by Chamberlain and Delabio (1965). The mineral...Outokumpu mine (Kouvo et al, 1963) and from the Muskox intrusion (Chamberlain and Delabio, 1965)indicate that...mackinawite takes up from 10 to 30 percentof the area of the pentlanditegrains.The mackinawite is usually...Upper Zone _L Main Magnetitite Main Zone Main Chromitite At Loolekop the study of a large number of polished |  | | Journal (article/letter/editorial) | | olivine cumulate (cyclic unit 2 containing the B-chromitite, Peridotite member, Ultramafic zone) from the...degrees, shows no visible disruption of the B-chromitite layers, has no obvious disturbance of the primary...the rock altered. (d) sample NB-9/955; thompsonite area, 0.9 mm across; 78.0 percent of plagioclase in the...Coleman, R.G.: Jadeite deposit of the Clear Creek area, New Idria district, San Benito County, California...high-temperature peridotite intrusions in the Lizard area, Cornwait. Jour. Petrology 5, i34-188 (1964) Hess |
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