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Capítulo de livro Revisado por pares

K. Benn,

... to south, the Opatica granite-gneiss belt, the Abitibi granite-greenstone Subprovince, and the Pontiac metasedimentary Subprovince. ... with middle crust that underlies greenstones of the Abitibi Subprovince. The Opatica belt can now be considered part of the Abitibi Subprovince, which represents one large tectonic terrane, the Abitibi-Opatica terrane. The boundary between the greenstones of the Abitibi Subprovince and the metasedimentary rocks of the Pontiac ... of the seismic reflection profiles suggests the Pontiac-Abitibi terrane suture involved wedging of older crust, underlying ...

Tópico(s): earthquake and tectonic studies

2006 - American Geophysical Union | Geophysical monograph

Artigo Revisado por pares

Donald W. Davis,

... Kewagama and Lac Caste Groups within the southern Abitibi subprovince. Youngest detrital zircon ages from these sequences ... bracket deposition of greywacke in the Pontiac and Abitibi subprovinces to 2685±3 Ma. In contrast, the ... detrital zircon ages from the Pontiac and the Abitibi metasedimentary rocks, as well as of dated igneous rocks from the southern Abitibi subprovince, all show that their major zircon populations ... range 2685–2710 Ma. The distributions for the Abitibi metaturbidites and dated igneous rocks are very similar, ...

Tópico(s): Geochemistry and Elemental Analysis

2002 - Elsevier BV | Precambrian Research

Artigo Revisado por pares

Gilles Bellefleur, Andrew J. Calvert, Michel Chouteau,

... precise estimates of reflector orientations beneath the Archean Abitibi Subprovince, using two distinct approaches based on Lithoprobe ... areas with distinctive geometry: reflectors beneath the southern Abitibi belt are oppositely dipping, and convergent at depth, ... the greenstone rocks; other reflectors beneath the northern Abitibi belt are, in general, subparallel, dipping at an ... of the Opatica Subprovince, located underneath the northern Abitibi belt. Lower-crustal reflectors have a similar, shallowly ...

Tópico(s): earthquake and tectonic studies

1998 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

Rui Feng, Jianzhong Fan, Robert Kerrich,

... were generated sequentially during evolution of the Archean Abitibi greenstone belt and adjacent high-grade metasedimentary Pontiac ... intrusions (the TGGM senries), such as the Lac Abitibi and Round Lake batholiths, developed in the Abitibi green-stone belt at approximately 2690 Ma. They ... emplaced between 2685 and 2676 Ma in the Abitibi greenstone belt. The Watabeag batholith of this series ... the Pontiac subprovince and Lacorne block of the Abitibi greenstone belt, a monzodiorite-monzonite-granodiorite-syenite (MMGS) ...

Tópico(s): Geochemistry and Elemental Analysis

1993 - | Economic Geology

Artigo Revisado por pares

John W.F. Ketchum, J. A. Ayer, O. van Breemen, Norman J. Pearson, J. K. Becker,

The Abitibi subprovince is widely regarded as a classic example of Neoarchean continental crust formed in an ensimatic setting. ... formed a contiguous block since the initiation of Abitibi magmatic activity at 2.75 Ga. A detailed ... of plutonic and volcanic rocks from the southwestern Abitibi provides evidence for the involvement of older crust during magma genesis near the Abitibi-Wawa boundary (Kapuskasing structural zone). Inherited zircons dated ... that the influence of older sialic crust during Abitibi volcanic and plutonic activity is restricted both in ...

Tópico(s): High-pressure geophysics and materials

2008 - | Economic Geology

Artigo Revisado por pares

Derek A. Wyman, Robert Kerrich,

... m.y. period of arc volcanism in the Abitibi subprovince, and the immediate onset of orogeny and ... demonstrate that syn-volcanic to syn-tectonic adakitic Abitibi granitoids were derived via slab melting. Deep seismic ... metasomatised mantle wedge throughout the entire period of Abitibi arc magmatism. Diamond-bearing lamprophyres in the Abitibi and adjacent Wawa subprovince are compositionally equivalent to ... than evidence of pre-existing sub-cratonic keels. Abitibi mantle plume- and subduction-related volcanism also demonstrates ...

Tópico(s): earthquake and tectonic studies

2008 - Elsevier BV | Precambrian Research

Artigo Revisado por pares

Erich Dimroth, Laszlo Imreh, Michel Rocheleau, Normand Goulet,

... comprises parts of the southern zone of the Abitibi greenstone belt and of the Bellecombe gneiss belt, ... Angliers greenstone belt. The stratigraphic sequence of the Abitibi Belt consists of (1) a lower ultramafic division; ( ... lower ultramafic division; these sediments coarsen toward the Abitibi Belt and toward the stratigraphic top. The volcanic ... lava plain covered the south part of the Abitibi Belt and the Bellecombe Belt. Faulting took place ... marine lava plain in the west of the Abitibi Belt, whereas flows erupted mainly from central volcanic ...

Tópico(s): Paleontology and Stratigraphy of Fossils

1982 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

Derek A. Wyman, R. Kerrich, Ali Polat,

... plutons or high magnesian andesites. Studies in the Abitibi–Wawa subprovince, allow these proposals to be evaluated ... slab melts from the earliest phases of the Abitibi–Wawa arc, resulting in the adakite–high magnesium ... may reflect plume controlled shallow subduction beneath the Abitibi belt that limited melting depths within a restricted ... source requirements of successively-formed components of the Abitibi–Wawa crust, and detailed seismic interpretations of crustal ... of an autochthonous mantle lithospheric root beneath the Abitibi–Wawa arc. Instead, the late diapiric ascent of ...

Tópico(s): earthquake and tectonic studies

2002 - Elsevier BV | Precambrian Research

Artigo Revisado por pares

Robert Kerrich, John Ludden,

... for fluid flow and hydrothermal alteration for the Abitibi greenstone belt are reviewed in the light of Lithoprobe results in the region. In the Abitibi greenstone belt, eruption of volcanic sequences over 2750- ... associated with greenstone belt asemblages in the northern Abitibi subprovince that were emplaced as a series of ... over the Opatica plutonic belt. In the southern Abitibi subprovince the hydrothermal deposits were associated with a ... cano genic sediments to depositional basins in the Abitibi, but siliciclastic sediments of mixed old 3 Ga ...

Tópico(s): earthquake and tectonic studies

2000 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

Rui Feng, R. Kerrich, Roland Maas,

The Abitibi greenstone belt (AGB) and Pontiac Subprovince (PS) in the southwestern Superior Province are adjacent greenstone-plutonic and ... of metasediments are present in the low-grade Abitibi southern volcanic zone: (1) a mafic-element-enriched ... Ti. The PS metasediments are essentially indistinguishable from Abitibi LMEP on the basis of majorelement and transition ... BaRb, TaNb, ThLa, and BaLa relative to the Abitibi LMEP. Two subtypes of REE patterns have been ... or Archean K-rich granites and volcanic equivalents. Abitibi metasediments have ϵNd (2.7 Ga) values of − ...

Tópico(s): Geology and Paleoclimatology Research

1993 - Elsevier BV | Geochimica et Cosmochimica Acta

Artigo Revisado por pares

K. Benn, E. W. Sawyer, Jean‐Luc Bouchez,

... 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 ... compression documented throughout southern Superior Province, including the Abitibi greenstone belt, D 1 is interpreted in terms ... southern Superior Province, the tectonic histories of the Abitibi and Opatica belts should not be considered separately. ... the present-day mid-crustal levels of the Abitibi greenstone belt, and to crystalline complexes within the ...

Tópico(s): earthquake and tectonic studies

1992 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

Rui Feng, R. Kerrich,

... grade Lacorne block within the low-grade Archean Abitibi greenstone belt have been dated by the single ... grade Lacorne block is not basement to the Abitibi supracrustal sequence (2747−2680 Ma). Existence of abundant ( ... zircons (>2750 Ma) suggests in turn that the Abitibi supracrustal rocks are not the source of the ... Ma). This contrasts with granitoid magmatism in the Abitibi greenstone belt which ended at ~2675 Ma. The Pontiac subprovince to the south of the Abitibi greenstone belt shares all of the above features ...

Tópico(s): earthquake and tectonic studies

1991 - Elsevier BV | Geochimica et Cosmochimica Acta

Artigo Revisado por pares

S. L. Jackson, R. H. Sutcliffe,

... belts (GB) (Michipicoten GB and possibly the northern Abitibi GB), ensimatic greenstone belts (southern Abitibi GB and Batchawana GB), and possibly a transitional ... the Kapuskasing Uplift, with that of the southern Abitibi GB. Furthermore, this lateral variability may have determined ... of crustal structure and tectonics for the southern Abitibi GB warrant examination.Thrusting of a juvenile, ensimatic southern Abitibi GB over a terrane containing evolved crust is ... with (i) the structural style of the southern Abitibi GB; (ii) juvenile southern Abitibi GB metavolcanic rocks ...

Tópico(s): Geochemistry and Elemental Analysis

1990 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

Derek A. Wyman, Robert Kerrich,

The Abitibi and Wawa subprovinces of the southern Superior Province differ in terms of the extent of pre-existing ... structures associated with large gold deposits from the Abitibi into the Wawa subprovince and the related occurrence ... Kaapvaal craton. Based on evidence preserved in the Abitibi–Wawa orogen, rapid crustal growth at ∼2.7 ... Key indicators in the model developed for the Abitibi–Wawa arc are the co-existence of plume- ... The variety of granitoid types found within the Abitibi–Wawa orogen demonstrates that local tectonic factors, rather ...

Tópico(s): Geochemistry and Geologic Mapping

2010 - NRC Research Press | Canadian Journal of Earth Sciences

Artigo Revisado por pares

J. A. Ayer, P. C. Thurston, Bruno Lafrance,

The Abitibi greenstone belt contains some of the world’s largest Cu-Zn and Au deposits and significant amounts ... the extensive overburden that covers most of the Abitibi greenstone belt. Thus, exploration will require improved knowledge ... this Special Issue are part of the Discover Abitibi Initiative, a geoscience program funded by federal, provincial, ... projects funded by Phase II of the Discover Abitibi Initiative which commenced in 2003 and was focused ... 1⇓), a high mineral potential portion of the Abitibi greenstone belt that has been the source of ...

Tópico(s): Mine drainage and remediation techniques

2008 - | Economic Geology