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Chapter 8.4 Eo- to Mesoarchean Terranes of the Superior Province and Their Tectonic Context

Chapter 8.4 Eo- to Mesoarchean Terranes of the Superior Province and Their Tectonic Context

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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



8.4-2. Tectonic Framework



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Fig. 8.4-1. Modified tectonic framework for the Superior Province, showing age range of continental

domains (identified in legend), distribution of oceanic domains and metasedimentary belts (unornamented) and Proterozoic cover (P ). Subdivisions of the Superior Province modified after Card and

Ciesielski (1986), Percival et al. (1992), Leclair et al. (2006) and Percival et al. (2006b). Abbreviations: AC: Ashuanipi complex; AT: Arnaud terrane; ERT: English River metasedimentary terrane;

EwT: Eastern Wabigoon terrane; HBT: Hudson Bay terrane; HT: Hawk terrane; KU: Kapuskasing uplift; MRVT: Minnesota River Valley terrane; MT: Marmion terrane; NCS: North Caribou

superterrane; NSS: Northern Superior superterrane; OnT: Opinaca metasedimentary terrane; OT:

Opatica terrane; PT: Pontiac metasedimentary terrane; QT: Quetico metasedimentary terrane; TT:

Troie terrane; WAT: Wawa–Abitibi terrane; WRT: Winnipeg River terrane; WwT: Western Wabigoon terrane; Inset: tectonic map of North America (after Hoffman, 1989) showing location of the

Superior Province.



A first-order feature of the Superior Province is its linear subprovinces of distinctive

lithological and structural character, accentuated by subparallel boundary faults (e.g., Card

and Ciesielski, 1986). Trends are generally east west in the south, WNW in the northwest,

and NW in the northeastern Superior (Fig. 8.4-1). Recent work based on isotopic and zircon inheritance studies has revealed fundamental age domains across the Superior Province

(Fig. 8.4-1). At least eight terranes of Eoarchean to Mesoarchean age are recognized, in

spite of pervasive Neoarchean magmatism, metamorphism and deformation. “Terranes”

are defined as tectonically bound regions with internal characteristics distinct from those

in adjacent regions prior to assembly of the Superior Province. They may comprise several

“domains” with distinct lithological characteristics that share a common basement. Terrane boundaries are commonly marked by synorogenic flysch deposits. “Superterranes”

carry metamorphic or deformational evidence of at least one amalgamation event before

Neoarchean Superior Province assembly. “Subprovince” is a general term describing a region with similar geological and geophysical characteristics.

The oldest crust (up to 3.8 Ga) occurs in the Northern Superior superterrane of the

northwestern Superior (NSS; Skulski et al., 2000; Böhm et al., this volume) and Hudson

Bay terrane to the northeast (O’Neil et al., this volume). To the south, a large region of

ca. 3.0 Ga crust, the North Caribou superterrane (Stott and Corfu, 1991; Stott, 1997), has

been interpreted as a continental nucleus during assembly of the Superior Province (cf.

Goodwin, 1968; Thurston et al., 1991; Williams et al., 1992; Stott, 1997; Thurston, 2002).

Farther south, the Winnipeg River (WR) and Marmion (MM) terranes are relatively small

continental fragments dating back to 3.4 and 3.0 Ga, respectively (Beakhouse, 1991; Tomlinson et al., 2004). In the far south, the Minnesota River Valley terrane (MRV) of unknown

extent contains remnants of crust as old as ca. 3.6 Ga (Goldich et al., 1984; Bickford et al.,

2006, this volume). To the east, the Opatica terrane has ancestry in the 2.8–2.9 Ga range

(Davis et al., 1995), as does the Arnaud terrane in the far northeast (Leclair et al., 2006).

Domains of oceanic ancestry, identified by submarine volcanic rocks with juvenile isotopic signatures, lack of inherited zircon and absence of clastic sedimentary input, separate

most of the continental fragments (Fig. 8.4-1). These dominantly greenstone-granite ter-



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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



ranes generally have long strike lengths and record geodynamic environments including

oceanic floor, plateaux, island arc and back-arc settings (e.g.„ Thurston 1994; Kerrich et

al., 1999). Examples include parts of the Oxford–Stull and southern La Grande domains in

the north, the western Wabigoon terrane in the west, and the Wawa–Abitibi terrane in the

southern Superior Province (Fig. 8.4-1).

Still younger features, the English River, Quetico and Pontiac metasedimentary terranes

(Breaks, 1991; Williams, 1991), separate some of the continental and oceanic domains.

Extending up to 1000 km along strike, these 50–100 km wide belts of metagreywacke,

migmatite and derived granite appear to represent thick syn-orogenic wedges (Davis, 1996,

1998, 2002), deposited, deformed and metamorphosed during collisional orogeny.



8.4-3. MICROCONTINENTAL FRAGMENTS

The ancient tectonic building blocks of the Superior Province comprise terranes of

continental affinity, with tectonostratigraphic histories independent of those of neighbouring regions prior to Neoarchean amalgamation (Percival et al., 2004a). The Eo- to

Mesoarchean terranes, separated by Neoarchean mobile belts, will be described in terms

of lithology, history and boundaries, beginning in the northwest, continuing through the

south, and terminating in the northeast (Fig. 8.4-1).

8.4-3.1. Northern Superior Superterrane

Dominated by granitic and gneissic rocks, the poorly exposed Northern Superior superterrane at the northern fringe of the Superior Province (Figs. 8.4-1 and 8.4-2) has been recognized on the basis of isotopic evidence (Skulski et al., 1999). In the west, the data include

ca. 3.5 Ga orthogneiss from the Assean Lake block (Böhm et al., 2000a) and supracrustal

units including iron formation, mafic-to intermediate volcanic rocks, and greywacke with

detrital zircon ages up to 3.9 Ga (Böhm et al., 2003). Orthogneiss with >3.5 Ga inherited

zircon ages has been recognized to the east (Skulski et al., 2000; Stone et al., 2004).

Ancient rocks throughout the Northern Superior superterrane have been strongly

reworked by metamorphism and magmatism. At Assean Lake (Fig. 8.4-2), tonalitetrondhjemite-granodiorite (TTG) magmatism occurred at 3.2–3.1 Ga, and amphibolitefacies metamorphism at 2.68 and 2.61 Ga (Böhm et al., 2003). In the Yelling Lake area

of Ontario (Fig. 8.4-2), magmatism at 2.85–2.81 Ga was followed by metamorphism and

further magmatism at 2.74–2.71 Ga (Skulski et al., 2000).



Fig. 8.4-2. (Next page.) Location of features referred to in the text. Abbreviations: ALB: Assean

Lake block; BRPC: Berens River plutonic complex; ELMC: English Lake magmatic complex;

GLTZ: Great Lakes tectonic zone; NSGB: North Spirit greenstone belt; NCGB: North Caribou greenstone belt; NKF: North Kenyon fault; SSGB: Savant-Sturgeon greenstone belt; WLGB: Wallace Lake

greenstone belt; YL: Yelling Lake. Additional abbreviations as in Fig. 8.4-1.



8.4-3. Microcontinental Fragments



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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



The Northern Superior superterrane is bounded to the south by the North Kenyon fault,

which juxtaposes it with the Oxford–Stull domain, a region of 2.84–2.71 Ga juvenile crust

(Skulski et al., 2000), and to the northwest by the Paleoproterozoic Trans-Hudson Orogen

(Fig. 8.4-1). Its northern and eastern limits are undefined owing to Paleozoic cover and

water of Hudson and James bays.

8.4-3.2. Hudson Bay Terrane

The Hudson Bay terrane (Leclair et al., 2006; Fig. 8.4-1) is located in the northeastern Superior Province, a region characterized dominantly by plutonic rocks and northnorthwesterly structural trends. Plutonic rocks include widespread charnockitic (pyroxenebearing) granitoid intrusions (Stern et al., 1994; Skulski et al., 1996; Rabeau, 2003; Bédard,

2003; Boily et al., 2004, 2006b; Stevenson et al., 2006). Supracrustal rocks occur as narrow, linear, lithologically diverse belts (<20 km wide by <120 km long) separated by

broad plutonic complexes (Percival and Card, 1992; Percival et al., 1994; Skulski et al.,

1996; Lin et al., 1996; Percival and Skulski, 2000; Boily and Dion, 2002; Berclaz et al.,

2003, 2004; Leclair et al., 2002a, 2006). The supracrustal belts are generally metamorphosed to amphibolite facies, but also occur at granulite and rarely, greenschist facies.

The Hudson Bay terrane is characterized by ancient Nd model ages, zircon inheritance

ages and rare Meso- and Eoarchean rock ages in several sub-regions, including the northern La Grande subprovince, Bienville, Tikkerutuk and Goudalie domains (Fig. 8.4-2).

In the northern La Grande subprovince, Mesoarchean basement (3.36–2.79 Ga) is unconformably overlain by clastic rocks (Roscoe and Donaldson, 1988) and 2.75–2.73 Ga

volcanic strata (Goutier and Dion, 2004). Igneous rocks include komatiites and related

ca. 2.82 Ga sills of probable rift origin (e.g., Skulski et al., 1988). Supracrustal rocks extend to the northeast as isolated volcano-sedimentary belts (Gosselin and Simard, 2001;

Thériault and Chevé, 2001; Simard et al., 2002). The Bienville domain is essentially composed of plutonic and gneissic rocks including TTG, granite-granodiorite plutonic suites

and their pyroxene-bearing equivalents (ca. 2.74–2.69 Ga) (Ciesielski, 2000; Simard et al.,

2004; Roy et al., 2004). They enclose rare supracrustal and older tonalitic units, many

of which can be correlated with units to the north. The plutonic rocks contain inherited

zircons ranging from 3.20–2.74 Ga and display Nd model ages as old as 3.36 Ga (Skulski et al., 1998; Isnard and Gariépy, 2004; Boily et al., 2004, 2006b; unpublished data

from J. David, written comm., 2006). The Tikkerutuk domain in the west is characterized

by abundant clinopyroxene-bearing tonalite-diorite, enderbite (2.73–2.69 Ga) and granite (2.72–2.69 Ga) enclosing older tonalitic units (2.84–2.75 Ga), with rare enclaves of

tonalitic gneiss (ca. 3.02 Ga) (Percival et al., 2001 and references therein; unpublished

data from J. David, written comm., 2006). Several isolated belts of supracrustal rocks

(2.76–2.70 Ga) occur mainly in the northern part of the domain (Maurice et al., 2005,

2006). The western Tikkerutuk domain is distinguished by generally older Nd model ages

(TDM = 3.2–4.0 Ga) (Nd isotopic data from Stern et al., 1994; Skulski et al., 1996; Rabeau,

2003; Boily et al., 2004, 2006b; Stevenson et al., 2006). It also contains the ca. 3.8–3.6 Ga

Nuvvuagittuq belt (Fig. 8.4-2: David et al., 2003, 2004; O’Neil et al., this volume), the oldest volcano-plutonic complex recognized in the Superior Province. The 8 km2 belt consists



8.4-3. Microcontinental Fragments



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mainly of Mg-rich amphibolite, with some ultramafic sills (Francis, 2004), metaconglomerate, and metamorphosed iron formation of metasedimentary origin (Dauphas et al., 2007;

O’Neil et al., this volume). Geochemical fingerprints suggest an arc-like setting (Cates and

Mojzsis, 2006). A tuffaceous unit returned a U-Pb zircon age of 3823 ± 18 Ma, whereas

tonalite gave 3650 ± 5 Ma and Nd model ages between 3.8 and 3.9 Ga (David et al., 2004).

Detrital zircons from conglomerate indicate oldest source ages around 3.73 Ga (Cates and

Mojzsis, 2006).

The Goudalie domain to the east is characterized by several small (up to 10 × 30 km)

supracrustal belts (2.88–2.71 Ga) surrounded by a plutonic complex including older (to

3.01 Ga), coeval and younger (2.72–2.67 Ga) units. The Vizien greenstone belt contains

tectonically intercalated 2.725 Ga volcanic rocks of continental arc affinity and 2.79 Ga

juvenile oceanic plateau rocks and was postulated to include a Neoarchean suture zone

(Skulski et al., 1996; Lin et al., 1996). The Goudalie domain records inherited zircon and

Nd model ages in the 2.8–3.3 Ga range (Rabeau, 2003; Boily et al., 2004, 2006b).

8.4-3.3. North Caribou Superterrane

The North Caribou superterrane (Fig. 8.4-1: Thurston et al., 1991) is the largest tract of

Mesoarchean rocks in the Superior Province (Stott, 1997). It is characterized by widespread

evidence for crust with ca. 3.0 Ga mantle extraction ages (Stevenson, 1995; Stevenson and

Patchett, 1990; Corfu et al., 1998; Hollings et al., 1999: Henry et al., 2000), and displays

evidence for continental breakup, as well as an amalgamation event prior to 2.87 Ga (Stott

et al., 1989; Thurston et al., 1991). Mesoarchean units have been variably reworked by

subsequent Archean magmatic and deformational events.

Within the greenstone belts, thin supracrustal packages are preserved sporadically

across the North Caribou superterrane (Thurston and Chivers, 1990; Thurston et al., 1991).

They consist of a lower, quartz-rich, coarse clastic unit, locally unconformable on basement, overlain by carbonate, iron formation, basaltic and komatiitic volcanic units. In different areas, the sequences have been interpreted as platformal cover strata (Thurston and

Chivers, 1990) and as plume-related rift deposits (Hollings and Kerrich, 1999; Hollings,

2002; Percival et al., 2002, 2006a). Evidence for plume-related rifting is based on the presence of quartz arenite and komatiitic rocks with enriched mantle geochemical signatures

(Tomlinson et al., 1998, 2001; Hollings and Kerrich, 1999).

Parts of the North Caribou superterrane have been assembled from older fragments

(Stott, 1997), although the early history is generally obscured by younger plutonism. Evidence of early tectono-metamorphism comes from the North Caribou greenstone belt

(Fig. 8.4-2), where ca. 2.98 and 2.92 Ga volcanic assemblages are intruded by the 2.87 Ga

North Caribou pluton, which is interpreted to postdate regional deformation and metamorphism (Stott et al., 1989).

The Oxford–Stull domain (Fig. 8.4-2: Thurston et al., 1991) represents the largely juvenile, 2.88–2.73 Ga continental northern margin of the 3 Ga North Caribou superterrane that

was tectonically imbricated with oceanic crustal fragments (Syme et al., 1999; Corkery et

al., 2000; Skulski et al., 2000; Stone et al., 2004). Its tectonostratigraphic features (Corkery



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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



et al., 2000) include 2.84–2.83 Ga tholeiitic mafic sequences and calc-alkaline arc volcanic

rocks with juvenile to locally enriched Nd isotopic composition, which are unconformably

overlain by <2.82 Ga sedimentary rocks that contain <2.94 Ga detrital zircons (Skulski et

al., 2000). Synvolcanic plutons associated with 2.84–2.72 Ga calc-alkaline volcanism are

isotopically juvenile in the Oxford–Stull domain, but have <3 Ga Nd model ages further

south, reflecting the influence of thicker North Caribou crust (Skulski et al., 2000). This

package was juxtaposed on D1 faults with submarine, depleted tholeiitic basalts prior to intrusion of 2.78 Ga tonalite (Corkery et al., 2000). Submarine arc volcanic rocks covered the

composite basement prior to ca. 2.72 Ga (Lin et al., 2006). Unconformably overlying the

shortened continental margin collage is a 2.722–2.705 Ga successor arc of calc-alkaline

to shoshonitic volcanic and associated sedimentary rocks (Brooks et al., 1982; Corkery

and Skulski, 1998; Corkery et al., 2000; Skulski et al., 2000; Stone et al., 2004; Lin et al.,

2006) that record an influx of local and exotic detrital zircons ranging in age from 2.704 to

3.65 Ga (Corkery et al., 1992; Corkery et al., 2000; Lin et al., 2006).

The Munro Lake and Island Lake domains (Fig. 8.4-2) comprise plutonic rocks with

several small supracrustal belts in the northern North Caribou superterrane (Stone et al.,

2004; Parks et al., 2006). In the Munro Lake domain, rift-related, quartzite locally interbedded with komatiite overlies 2.883–2.865 Ga tonalite (Stone et al., 2004; Corkery et al., in

prep.). Tonalite and granodiorite plutons across the Munro and Island Lake domains have

U/Pb ages ranging from 2.88–2.70 Ga, and have 3.05–2.71 Ga Nd model ages reflecting

variable recycling of North Caribou age crust (Turek et al., 1986; Stevenson and Turek,

1992; Skulski et al., 2000).

To the south, the Island Lake domain includes 2.89, 2.85 and 2.74 Ga volcanic sequences in a series of structural panels (Parks et al., 2006). Diverse clastic sedimentary

sequences were deposited synvolcanically at <2.84 >2.744 Ga, and post-volcanically at

<2.71 Ga. All sequences have detrital zircon U/Pb ages that range from 2.938–2.711 Ga

(Corfu and Lin, 2000), consistent with North Caribou provenance.

The central North Caribou superterrane, which is dominated by 2.745–2.698 Ga calcalkaline, peraluminous and sanukitoid granitoid plutons of the Berens River plutonic complex (Fig. 8.4-2: Stone, 1998; Corfu and Stone, 1998a), preserves several remnants of ca.

3.0 Ga basement crust. Some of the oldest rocks are 3.02 Ga felsic volcanic rocks of the

North Spirit assemblage (Fig. 8.4-2: Corfu and Wood, 1986), with juvenile 3.1 and younger

Nd model ages (Stevenson, 1995).

8.4-3.3.1. English Lake complex

One of the largest and best preserved remnants of North Caribou crust occurs in the southwestern corner, where Krogh et al. (1974) first recognized 3.0 Ga rocks. Here, rocks of the

English Lake complex (Fig. 8.4-2) consist of mantle-derived ultramafic through tonalitic

compositions (Whalen et al., 2003). Detailed petrological, geochemical and geochronological studies provide insight into petrogenetic processes active in formation of the English

Lake complex.

The complex consists predominantly of weakly metamorphosed tonalite and gneissic equivalents, with diorite, gabbro, anorthosite, hornblendite and metabasite (Fig. 8.4-



8.4-3. Microcontinental Fragments



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Fig. 8.4-3. Photographs of well preserved, Mesoarchean, magmatic and metamorphic textures of the

English Lake magmatic complex: (a) multiple cross-cutting relationships among tonalitic, mafic and

anorthositic magmatic phases, which have yielded ages between 3007 and 2992 Ma (Whalen et al.,

2003); (b) graded magmatic layering in anorthosite and gabbroic anorthosite; note rafted gabbroic

fragment; (c) ultramafic breccia showing fragments of pyroxenite (pale) and gabbro (dark) in matrix

of igneous hornblendite; (d) garnet-clinopyroxene-hornblende-plagioclase metabasite; metamorphic

zircon from this rock yielded a U-Pb age of 2997 Ma (Percival et al., 2006a).



3(a–d); Percival et al., 2006a) that yield U-Pb zircon crystallization ages in the range

3006–2992 Ma (Whalen et al., 2003). Mafic through felsic components share common

geochemical attributes, including low trace-element abundances, slight LREE enrichment,

and generally prominent negative Th and Nb anomalies (Whalen et al., 2003). These features have been interpreted as the signature of arc magmas produced in a mantle wedge

fluxed by fluids derived from serpentinite dehydration (op. cit.). At deep structural levels,



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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



Fig. 8.4-3. (Continued.)



mafic layers up to tens of metres thick (Fig. 8.4-3(d)) contain the metamorphic assemblage

garnet-clinopyroxene-hornblende-plagioclase-quartz, which provides P-T estimates in the

range 12 kbar, 850 ◦ C (Percival et al., 2006a), much greater than the regional background

erosion level (ca. 4 kbar; Stone, 2000). Metamorphic zircons yielded a syn-magmatic U-Pb

age of 2997 ± 4 Ma (Percival et al., 2006a), suggesting that the crust attained a thickness

of at least 36 km during magmatic construction.

A deformation fabric within the complex includes ductile high-strain zones up to several

metres wide with dextral transcurrent kinematic indicators (Percival and Whalen, 2000).

The shear zones are transected by dykes and plutons of late-tectonic biotite granodiorite,

dated at 2941 ± 2 Ma (Percival et al., 2006a). The observations suggest that a Mesoarchean

(ca. 2940 Ma) tectonomagmatic event affected the North Caribou superterrane in this area.

It may correspond to a >2920 Ma D1 event identified nearby in the Wallace Lake belt,



8.4-3. Microcontinental Fragments



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Fig. 8.4-4. Representative rock types of the Mesoarchean Lewis-Storey rift assemblage; (a) quartz

arenite with centimetre-scale bedding; (b) spinifex-textured komatiite (white arrows mark acicular

olivine crystals).



which is characterized by high-strain zones and tectonic inversion (Sasseville, 2002; Sasseville et al., 2006).

8.4-3.3.2. Lewis-Storey Rift Assemblage

The Lewis-Storey assemblage is a sedimentary-volcanic sequence that sits unconformably

on 3.0 Ga tonalitic basement at the southwestern margin of the North Caribou superterrane

(Percival et al., 2002, 2006a). Basal arkosic grit (Bailes and Percival, 2005) is overlain

by thinly laminated, fine-grained quartz arenite units up to 3 m thick (Fig. 8.4-4(a)), including fuchsitic horizons. Quartz arenite carries a single population of detrital zircons

with SHRIMP ages centered around 2991 ± 4 Ma, suggesting local derivation (Percival et

al., 2006a). A unit of spinifex-textured komatiite (Fig. 8.4-4(b)) and derived serpentinite



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Chapter 8.4: Eo- to Mesoarchean Terranes of the Superior Province



structurally overlies the quartz arenite and is succeeded by ca. 5 m of oxide and carbonate

facies iron formation. Sills of mafic and rare felsic composition intrude the basement and

sedimentary-volcanic sequence. A quartz-porphyritic rhyolite sill cutting basal grit yielded

igneous zircons of 2978 ± 3 Ma (Percival et al., 2006a).

The sedimentary-volcanic sequence and associated mafic to felsic sills are interpreted to

mark an ancient (ca. 2980 Ma) rifted margin of the North Caribou superterrane. Basal grit

may have developed through chemical weathering of tonalite during uplift preceding rifting

(cf. Rainbird and Ernst, 2001). The presence of komatiite, generated in anomalously hot

mantle, and possible evidence of early uplift and weathering, support a model of plumedriven rifting (e.g., Bleeker et al., 1999). An age gap of 255 million years separates the

Lewis-Storey assemblage from juvenile Neoarchean rocks to the southwest, which are

juxtaposed along a Neoarchean (ca. 2.70 Ga) D1 transcurrent shear zone (Percival et al.,

2006a). These observations lead to the conclusion that an open ocean existed from ca. 2980

to 2700 Ma, and that a 280 My Wilson cycle is recorded at the southeastern margin of the

North Caribou superterrane.

8.4-3.3.3. Uchi domain

The Uchi domain preserves ca. 300 My of tectonostratigraphic evolution along the southern

margin of the North Caribou superterrane (Fig. 8.4-2: Stott and Corfu, 1991; Corfu and

Stott, 1993a; 1996; Hollings et al., 2000; Sanborn-Barrie et al., 2001; Young et al., 2006).

Chronostratigraphic correlations have been established within greenstone belts over a strike

length of at least 500 km.

The stratigraphic sequence built on North Caribou basement, records 2.99–2.96 Ga rifting (Tomlinson et al., 1998; Sanborn-Barrie et al., 2004), several episodes of continental arc

magmatism (2.94–2.91, 2.89, 2.87, 2.745–2.734 Ga; Henry et al., 2000; Sanborn-Barrie et

al., 2001, 2004), intra-arc rifting, several phases of deformation and associated sedimentation. A deformation event and unconformity or disconformity separate Mesoarchean from

Neoarchean strata across the Uchi domain. Juvenile volcanic rocks (2.73–2.713 Ga) along

the southern margin may have formed on thin North Caribou crust, or may be part of an

accreted oceanic terrane (Percival et al., 2006a).

8.4-3.4. Winnipeg River Terrane

The Winnipeg River terrane includes plutonic rocks exposed north and east of the western

Wabigoon volcanic domain. It consists of the Winnipeg River subprovince of Beakhouse

(1991), a >500 km long terrane composed of Neoarchean plutonic rocks with Meso- to

Paleoarchean inheritance; and a Neoarchean plutonic domain to the southeast that contains

scattered remnants of Mesoarchean crust and isotopic evidence for recycled 3.4–3.0 Ga

material (Tomlinson and Percival, 2000; Tomlinson et al., 2004; Whalen et al., 2002, 2004).

With inheritance back to ca. 3.4 Ga (Henry et al., 1998; Tomlinson and Dickin, 2003), the

Winnipeg River terrane is distinct from the Northern Superior and North Caribou superterranes to the north and the Marmion terrane to the south (described below). It also carries a



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Chapter 8.4 Eo- to Mesoarchean Terranes of the Superior Province and Their Tectonic Context

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