Title | The Kivalliq Igneous Suite: Anorogenic bimodal magmatism at 1.75 Ga in the western Churchill Province, Canada |
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Author | Peterson, T D; Scott, J M J; LeCheminant, A N; Jefferson, C W; Pehrsson, S J |
Source | Precambrian Research vol. 262, 2015 p. 101-119, https://doi.org/10.1016/j.precamres.2015.02.019 |
Image |  |
Year | 2015 |
Alt Series | Earth Sciences Sector, Contribution Series 20130347 |
Publisher | Elsevier BV |
Document | serial |
Lang. | English |
Media | paper; digital; on-line |
File format | pdf; html |
Province | Alberta; Manitoba; Northwest Territories; Nunavut; Ontario; Saskatchewan |
NTS | 36N/06; 36N/07; 36N/08; 36B/09; 36N/10; 36N/11; 36N/14; 36N/15; 36N/16; 37B; 37C; 37F; 37G; 38A/03; 38A/04; 38A/05; 38A/11; 38B; 38C; 43J/09; 43J/10; 43J/11; 43J/12; 43J/13; 43J/14; 43J/15; 43J/16; 43K/09;
43K/10; 43K/11; 43K/12; 43K/13; 43K/14; 43K/15; 43K/16; 43L/09; 43L/10; 43L/11; 43L/12; 43L/13; 43L/14; 43L/15; 43L/16; 43M; 43N; 43O; 44D/03; 44D/04; 44D/05; 45J/03; 45J/04; 45J/05; 45J/06; 45J/07; 45J/09; 45J/10; 45J/11; 45J/12; 45J/13; 45J/14;
45J/15; 45J/16; 45M/09; 45M/10; 45M/11; 45M/14; 45M/15; 45M/16; 45N/02; 45N/03; 45N/04; 45N/05; 45N/06; 45N/07; 45N/09; 45N/10; 45N/11; 45N/12; 45N/13; 45N/14; 45N/15; 45N/16; 45O/09; 45O/10; 45O/16; 45P/09; 45P/10; 45P/11; 45P/12; 45P/13; 45P/14;
45P/15; 45P/16; 46; 47; 48A; 48B; 48C; 48D; 53J/09; 53J/10; 53J/11; 53J/12; 53J/13; 53J/14; 53J/15; 53J/16; 53K/09; 53K/10; 53K/11; 53K/12; 53K/13; 53K/14; 53K/15; 53K/16; 53L/09; 53L/10; 53L/11; 53L/12; 53L/13; 53L/14; 53L/15; 53L/16; 53M; 53N; 53O;
53P; 54A; 54B; 54C; 54D; 54E; 54F; 54G/01; 54G/02; 54G/03; 54G/04; 54G/06; 54G/07; 54K; 54L; 54M; 55D; 55E; 55F/12; 55F/13; 55F/14; 55J/13; 55J/14; 55F/15; 55K; 55L; 55M; 55N; 55O; 56; 57; 58A; 58B; 58C; 58D; 62E; 62F/04; 62F/05; 62F/11; 62F/12;
62K/04; 62K/05; 62K/11; 62K/12; 62L; 62M; 62N; 62O/04; 62O/05; 62O/11; 62O/12; 63B/04; 63B/05; 63B/11; 63B/12; 63C; 63D; 63E; 63F; 63G/04; 63G/05; 63G/11; 63G/12; 63I/09; 63I/10; 63I/11; 63I/12; 63I/13; 63I/14; 63I/15; 63I/16; 63J/04; 63J/05; 63J/06;
63J/07; 63J/08; 63J/09; 63J/10; 63J/11; 63J/12; 63J/13; 63J/14; 63J/15; 63J/16; 63K; 63L; 63M; 63N; 63O; 63P; 64; 65; 66; 67; 68A; 68B; 68C; 68D; 72E; 72F; 72G; 72H; 72I; 72J; 72K; 72L; 72M; 72N; 72O; 72P; 73; 74; 75; 76; 77; 78A; 78B; 78D; 82P/01;
82P/08; 82P/09; 82P/16; 83A/01; 83A/02; 83A/07; 83A/08; 83A/09; 83A/10; 83A/15; 83A/16; 83H/01; 83H/02; 83H/07; 83H/08; 83H/09; 83H/10; 83H/15; 83H/16; 83I/01; 83I/02; 83I/07; 83I/08; 83I/09; 83I/10; 83I/15; 83I/16; 83P/01; 83P/02; 83P/07; 83P/08;
83P/09; 83P/10; 83P/15; 83P/16; 84A; 84G/01; 84G/08; 84G/09; 84G/10; 84G/15; 84G/16; 84H/01; 84J/01; 84J/02; 84J/06; 84J/07; 84J/08; 84J/09; 84J/10; 84J/11; 84J/14; 84J/15; 84J/16; 84O; 84P; 85A; 85B; 85C/01; 85C/08; 85C/09; 85C/10; 85C/15; 85C/16;
85F/01; 85F/02; 85F/07; 85F/08; 85F/09; 85F/10; 85F/11; 85F/14; 85F/15; 85F/16; 85G; 85H; 85I; 85J; 85K; 85L/16; 85M/01; 85M/02; 85M/07; 85M/08; 85M/09; 85M/10; 85M/11; 85M/14; 85M/15; 85M/16; 85N; 85O; 85P; 86; 87; 88A; 88B; 88D; 96A/16; 96B;
96H/01; 96H/02; 96H/07; 96H/08; 96H/09; 96H/10; 96H/15; 96H/16; 96I/16; 96N/01; 96N/08; 96N/09; 96N/10; 96N/15; 96N/16; 97A; 97C/08; 97C/09; 97C/10; 97C/15; 97C/16; 97D; 98A/01; 98A/02; 98A/08 |
Lat/Long WENS | -126.0000 -74.0000 73.7500 49.0000 |
Subjects | tectonics; igneous and metamorphic petrology; geochemistry; economic geology; trace elements; magmatism; igneous rocks; granites; rhyolites; volcanic rocks; mineral assemblages; tectonic setting;
petrographic analyses; geochemical analyses; uranium geochemistry; rare earths geochemistry; thorium geochemistry; yttrium geochemistry; zirconium geochemistry; mafic rocks; dykes; Kivalliq Igneous Suit; Churchill Province; Nueltin Granite; Pitz
Formation; Dubawnt Supergroup; Wharton Group; Snowbird Tectonic Zone; Swift Current Anorogenic Province; McRae Lake Dyke; Nuna; Proterozoic |
Illustrations | geological sketch maps; photographs |
Program | GEM:
Geo-mapping for Energy and Minerals Uranium |
Released | 2015 06 01 |
Abstract | The Kivalliq Igneous Suite (1.77--1.73 Ga) includes the Nueltin Granite intrusions; gabbro and anorthosite intrusions; three swarms of mafic dykes; and basalt, rhyolite and pyroclastic rocks of the Pitz
Formation (Wharton Group, middle Dubawnt Supergroup). It was emplaced in the reworked Archaean hinterland of the trans-Hudson orogen, in the central western Churchill Province (WCP) of the Canadian Shield. The Nueltin granites have field relations,
mineral assemblages, and compositions typical of metaluminous to peraluminous, Proterozoic to Recent rapakivi granites, and the suite comprises a classic bimodal anorogenic province. Kivalliq rhyolites/granites were erupted/emplaced in a N--S band
(the "Nueltin corridor") about 700 km long and 300 km wide, with volcanic rocks and dykes concentrated at the north end and coarse plutonic rocks to the south. The McRae Lake dyke swarm originates among three prominent gabbro/anorthosite intrusions
inside the corridor, and forms a narrow array extending a minimum of 600 km to the NE along the central axis of the WCP. Early mafic rocks (intrusions and some lavas, 1.77 Ga) had an alkali basalt parent, with subalkaline basalts (sills, dykes, and
mafic enclaves) present at the peak time of granite emplacement (1.75 Ga). Average initial ?Nd of basaltic rocks at 1.75 Ga is -4.0, indicating a significant crustal component. Sm--Nd depleted mantle model ages of granites and rhyolites (average
initial ?Nd = -8.7) range from 2.2 to 3 Ga, consistent with melted Archaean crust variably mixed with juvenile basalt. Metallogenic prospects of the Kivalliq Suite include U-Th-Zr-Y-REE enriched granite and syenite, epithermal Ag/Au at silicic
centres (including mafic/felsic ring complexes), and Pb--Cu sulphides associated with mafic intrusions. Topaz rhyolites are present, but Sn-enriched rocks have not been observed. The Kivalliq Suite is one of about 15 prominent anorogenic provinces
and dyke swarms which erupted within the Nuna supercontinent at ca. 1.75 Ga, and the thermal effects of the Kivalliq event are recorded in U--Pb and K--Ar data throughout most of the western Churchill Province. |
Summary | (Plain Language Summary, not published) The Kivalliq Igneous Suite is a typical anorogenic granite-basalt province within the central Western Churchill Province. It is exceptional for its size
(ca. 1000 km long) the extent of preservation of volcanic rocks, and for the province-wide extent of related thermal events caused by basaltic underplating of the crust. The basalt was more alkaline, and deeper sourced, than that present in most
anorogenic suites. Economic mineral prospects include U-Th-REE-rich intrusions, Ag-Au hydroterhmal systems, and Pb-Cu vein/replacement systems. |
GEOSCAN ID | 293384 |
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