scholarly journals Petrogenetic and geodynamic origin of the Neoarchean Doré Lake Complex, Abitibi subprovince, Superior Province, Canada

2017 ◽  
Vol 107 (3) ◽  
pp. 811-843 ◽  
Author(s):  
Ali Polat ◽  
Robert Frei ◽  
Fred J. Longstaffe ◽  
Ryan Woods
Keyword(s):  
Superior Province ◽  
Abitibi Subprovince

Metamorphic Gradient: A Regional-Scale Area Selection Criterion for Gold in the Northeastern Superior Province, Eastern Canadian Shield

SEG Discovery ◽  
2007 ◽  
pp. 1-15
Author(s):  
Michel Gauthier ◽  
Sylvain Trépanier ◽  
Stephen Gardoll
Keyword(s):  
Regional Scale ◽  
Selection Criterion ◽  
Superior Province ◽  
James Bay ◽  
Area Selection ◽  
The North ◽  
First Pass ◽  
Abitibi Subprovince ◽  
Frontier Region ◽  
Metamorphic Gradient

ABSTRACT One hundred years after the first gold discoveries in the Abitibi subprovince, the Archean James Bay region to the north is experiencing a major exploration boom. Poor geologic coverage in this part of the northeastern Superior province has hindered the application of traditional Abitibi exploration criteria such as crustal-scale faults and “Timiskaming-type” sedimentary rocks. New area selection criteria are needed for successful greenfield exploration in this frontier region, and the use of steep metamorphic gradients is presented as a possible alternative. The statistical robustness of the metamorphic gradient area selection criterion was confirmed by using the curve of the receiver operating characteristic (ROC) to estimate the correlation between metamorphic fronts and the distribution of known Abitibi orogenic gold producers. The criterion was then applied to the James Bay region during a first-pass craton-scale exploration program. This was part of the strategy that led to the discovery of the Eleonore multimillion-ounce gold deposit in 2004.

Plumbing and architecture of a crustal mineralizing system in the Archean Superior Province, Canada

2021 ◽  
Author(s):  
Eric Roots ◽  
Graham Hill ◽  
Ben M. Frieman ◽  
James A. Craven ◽  
Richard S. Smith ◽  
...  
Keyword(s):  
Upper Mantle ◽  
Spatial Association ◽  
Three Dimensional ◽  
3D Models ◽  
Superior Province ◽  
Seismic Reflection Data ◽  
Reflection Data ◽  
Abitibi Subprovince ◽  
Lower Crustal

<p>The role of melts and magmatic/metamorphic fluids in mineralization processes is well established. However, the role of crustal architecture in defining source and sink zones in the middle to lower crust remains enigmatic. Integration of three dimensional magnetotelluric (MT) modelling and seismic reflection data across the Archean Abitibi greenstone belt of the Superior Province, Canada, reveals a ‘whole-of-crust’ mineralizing system and highlights the controls by crustal architecture on metallogenetic processes. Electrically conductive conduits in an otherwise resistive upper crust are coincident with truncations and offsets of seismic reflections that are mostly interpreted as major brittle-ductile fault zones. The spatial association between these features and low resistivity zones imaged in the 3D models suggest that these zones acted as pathways through which fluids and melts ascended toward the surface. At mid-crustal levels, these ‘conduit’ zones connect to ~50 km long, north-south striking conductors, and are inferred to represent graphite and/or sulphide deposited from cooling fluids. At upper mantle to lower crustal depths, east-west trending conductive zones dominate and display shallow dips. The upper mantle features are broadly coincident with the surface traces of the major deformation zones with which a large proportion of the gold endowment is associated. We suggest that these deep conductors represent interconnected graphitic zones perhaps augmented by sulphides that are relicts from metamorphic fluid and melt emplacement associated primarily with the later stages of regional deformation.  Thus, from the combined MT and seismic data, we develop a crustal-scale architectural model that is consistent with existing geological and deformational models, providing constraints on the sources for and signatures of fluid and magma emplacement that resulted in widespread metallogenesis in the Abitibi Subprovince.</p>

Paleomagnetism of the 1.1 Ga Lackner Lake Complex and tectonics of the Kapuskasing Structural Zone

1989 ◽  
Vol 26 (9) ◽  
pp. 1778-1783 ◽  
Author(s):  
D. T. A. Symons
Keyword(s):  
Fault Zone ◽  
Canadian Shield ◽  
Superior Province ◽  
Thermal Demagnetization ◽  
Abitibi Subprovince ◽  
Reversed Polarity ◽  
Middle Proterozoic

The Middle Proterozoic Lackner Lake Complex is a circular alkalic syenite–carbonatite stock with a diameter of about 5.5 km. It intrudes granulite-rank Archean gneisses in the Kapuskasing Structural Zone of the Wawa Subprovince in the Superior Province of the Canadian Shield. It adjoins the Ivanhoe Lake fault zone, which forms the boundary with the Abitibi Subprovince and is the probable locus of maximum motion between the subprovinces. Specimens from 18 sites in the complex were analyzed paleomagnetically by alternating-field and thermal demagnetization and by saturation isothermal remanence tests. Large, recent viscous remanence components required removal before a stable remanence with a mean direction of 305.4°, 64.1 °(α95 = 5.2°) was isolated. Its pole of 53.7°N, 156.5°W (dp = 6.7°, dm = 8.3°) indicates emplacement at 1108 ± 10 Ma during a brief normal interval in a predominantly reversed-polarity time. This study indicates that there has been no postintrusion tilting of the Kapuskasing Structural Zone and that postintrusion uplift by unroofing did not exceed about 8 km.

Orogen parallel and transverse shearing in the Opatica belt, Quebec: implications for the structure of the Abitibi Subprovince

1992 ◽  
Vol 29 (11) ◽  
pp. 2429-2444 ◽  
Author(s):  
Keith Benn ◽  
Edward W. Sawyer ◽  
Jean-Luc Bouchez
Keyword(s):  
Greenstone Belt ◽  
Regional Scale ◽  
Structural Evolution ◽  
Fault Zones ◽  
Crustal Thickening ◽  
Superior Province ◽  
Northern Margin ◽  
Abitibi Greenstone Belt ◽  
Ductile Shearing ◽  
Abitibi Subprovince

The late Archean Opatica granitoid-gneiss belt is situated within the northern Abitibi Subprovince, along the northern margin of the Abitibi greenstone belt. Approximately 200 km of structural section was mapped along three traverses within the previously unstudied Opatica belt. The earliest preserved structures are penetrative foliations and stretching and mineral lineations recording regional ductile shearing (D1). Late-D1 deformation was concentrated into kilometre-scale ductile fault zones, typically with L > S tectonite fabrics. Two families of lineations are associated with D1, indicating shearing both parallel and transverse to the east-northeast trend of the belt. Lineations trending east-northeast or northwest–southeast tend to be dominant within domains separated by major fault zones. In light of the abundant evidence for early north–south compression documented throughout southern Superior Province, including the Abitibi greenstone belt, D1 is interpreted in terms of mid-crustal thrusting, probably resulting in considerable crustal thickening. Movement-sense indicators suggest that thrusting was dominantly southward vergent. D2 deformation resulted in the development of vertical, regional-scale dextral and sinistral transcurrent fault zones and open to tight upright horizontal folds of D1 fabrics. In the context of late Archean orogenesis in southern Superior Province, the tectonic histories of the Abitibi and Opatica belts should not be considered separately. The Opatica belt may correlate with the present-day mid-crustal levels of the Abitibi greenstone belt, and to crystalline complexes within the Abitibi belt. It is suggested that the Abitibi Subprovince should be viewed, at the regional scale, as a dominantly southward-vergent orogenic belt. This work demonstrates that structural study of granitoid-gneiss belts adjacent to greenstone belts can shed considerable light on the regional structure and structural evolution of late Archean terranes.

Age and isotopic composition of late Archean leucogranites: implications for continental collision in the western Superior Province

1999 ◽  
Vol 36 (4) ◽  
pp. 495-510 ◽  
Author(s):  
Y Larbi ◽  
R Stevenson ◽  
F Breaks ◽  
N Machado ◽  
C Gariépy
Keyword(s):  
Rare Metal ◽  
Superior Province ◽  
Similar Data ◽  
Metasedimentary Rocks ◽  
Northwestern Ontario ◽  
Metavolcanic Rocks ◽  
Abitibi Subprovince ◽  
Winnipeg River ◽  
Rare Metal Mineralization ◽  
Mantle Component

U-Pb and Sm-Nd isotopic data are presented for leucogranites and pegmatites from the boundary zones of the English River, Winnipeg River, and Wabigoon subprovinces in the late Archean Superior Province of northwestern Ontario. The Ghost Lake batholith and the Separation Rapids pluton are posttectonic, rare-metal-bearing, S-type leucogranites that were generated during the final stages of the amalgamation of the Superior Province. U-Pb dating of monazites yields ages of 2650 ± 3 Ma for a pegmatite from the Dryden area and 2646 ± 2 Ma for the Separation Rapids pluton. Sm-Nd data from these granitoids are compared with similar data from late Archean intrusions and adjacent rocks from the same regions. Values of εNd range from 0 to +2 for pretectonic tonalites, from -2 to +2 for both the Ghost Lake batholith and the Separation Rapids pluton, from +1 to +3.5 for metavolcanic rocks, and from -0.5 to -1.5 for metasedimentary rocks. There is an overall trend of decreasing εNd values from pretectonic tonalites to the latest leucocratic pegmatites. This reflects the origin of more and more granitoids as a result of anatexis as the crust grew and thickened through accretion. The ranges of εNd values found among leucogranites from the two regions overlap with the isotopic values of the basalts and sediments. This suggests that the leucogranites were generated by similar processes involving both a crustal and a juvenile mantle component. Furthermore, the ages from this study and from pegmatites (2652-2643 Ma) in the Bird River greenstone belt provide the best estimate of the age of rare metal mineralization in the western Superior Province. Similar ages (2651-2639 Ma) for rare-metal-bearing leucogranites in southern Abitibi subprovince suggest a specific period of emplacement over a wide area.

A 3D gravity data interpretation of the Matagami mining camp, Abitibi Subprovince, Superior Province, Québec, Canada

2011 ◽  
Vol 75 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Pierre Boszczuk ◽  
Li Zhen Cheng ◽  
Hanafi Hammouche ◽  
Patrice Roy ◽  
Sylvain Lacroix ◽  
...  
Keyword(s):  
Gravity Data ◽  
Data Interpretation ◽  
Superior Province ◽  
Abitibi Subprovince ◽  
3D Gravity

Geophysical evidence for a pre-impact Sudbury dome, southern Superior Province, Canada

2005 ◽  
Vol 42 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Stephen A Prevec ◽  
Duncan R Cowan ◽  
Gordon RJ Cooper
Keyword(s):  
Thermal Regime ◽  
Superior Province ◽  
Geochronological Data ◽  
Subsequent Evolution ◽  
Igneous Complex ◽  
Sudbury Igneous Complex ◽  
Gneiss Complex ◽  
Sudbury Structure ◽  
Abitibi Subprovince

New filtering of aeromagnetic images of the Sudbury area indicates the existence of a large, elliptical feature that appears to underlie the deformed Sudbury Structure in the region of the exposed Levack Gneiss Complex, such that the two features have long axes which are significantly orthogonal to one another. A north–south-oriented ellipse appears to be crosscut by that of the Sudbury Structure and does not correspond to known local lithological or structural trends. The magnetic images, combined with existing tectonic, petrological, geothermometric and geobarometric, and geochronological data, are used to suggest the existence of a pre-impact crustal dome in the southernmost Abitibi subprovince, probably related to ca. 2450 Ma rifting and magmatism in the area. This is consistent with existing petrological and tectonic evidence from a variety of sources. Although the doming is itself unrelated to the ca. 1850 Ma Sudbury event, it may have affected the thermal regime existing at the time of impact, which would have profound implications for the subsequent evolution of the Sudbury Igneous Complex.

Age and timing of igneous activity in the Temagami greenstone belt, Ontario: a preliminary report

1991 ◽  
Vol 28 (11) ◽  
pp. 1873-1876 ◽  
Author(s):  
R. J. Bowins ◽  
L. M. Heaman
Keyword(s):  
Greenstone Belt ◽  
Preliminary Report ◽  
Superior Province ◽  
Early Proterozoic ◽  
The North ◽  
Intrusive Rocks ◽  
Abitibi Subprovince ◽  
Igneous Activity ◽  
The Town ◽  
Volcanic Cycle

The southernmost remnants of Archean supracrustal and intrusive rocks in eastern Ontario are exposed through a window in the Early Proterozoic Huronian Supergroup near the town of Temagami. U–Pb zircon ages from this area indicate the presence of some of the oldest felsic magmatism so far discovered in this portion of the Superior Province. The Iceland Lake pluton (2736 ± 2 Ma) and a nearby rhyolite flow ([Formula: see text]) are contemporaneous, which establishes that at least some of the intrusive rocks in the region are synvolcanic and coeval with the oldest volcanic cycle. The youngest plutonic activity is the emplacement of a late rhyolite porphyry dike at 2687 ± 2 Ma, an age that is bracketed by the 2675–2700 Ma emplacement ages of late internal plutons found throughout the Abitibi Subprovince. The 2736 Ma dates, however, are older than the nearest portion of the exposed Abitibi, some 120 km to the north near Kirkland Lake.

Regional variation in paleomagnetic polarity of the Matachewan dyke swarm related to the Kapuskasing Structural Zone, Ontario

1990 ◽  
Vol 27 (2) ◽  
pp. 200-211 ◽  
Author(s):  
M. P. Bates ◽  
H. C. Halls
Keyword(s):  
Lower Crust ◽  
Regional Variation ◽  
Canadian Shield ◽  
Dyke Swarm ◽  
Published Data ◽  
Superior Province ◽  
The North ◽  
Paleomagnetic Pole ◽  
Abitibi Subprovince

The 2.45 Ga Matachewan dykes from the Abitibi Subprovince of the Canadian Shield yield a mean paleomagnetic pole of 42°N, 58°E (α95 = 3°; N (sites) = 36), which is a composite of new and previously published data. Domains of paleomagnetic polarity are defined: an area of dykes predominantly of reversed magnetization in the Abitibi Subprovince contrasts with an area of exclusively normal dykes to the north. The polarity domains are separated by faults related to the 1.95 Ga uplift and exposure of the lower crust in the Kapuskasing Structural Zone and therefore reflect Hudsonian age tectonics in the Archean Superior Province.

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