Punctuated anorogenic magmatism

Martin, Robert F.; Sokolov, Maria; Magaji, S. S.

doi:10.1016/j.lithos.2012.05.020

Cited by 16 publications

(11 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Importantly, only two of these provinces (both in the North China craton) erupted within lithosphere that was not already part of Nuna. Many previous authors have concluded that rapakivi granite provinces are commonly associated with periods of time following large-scale collisions and hence, are symptomatic of episodes of continental amalgamation and supercontinent formation (e.g., Windley, 1993;Vigneresse, 2005;Zhang et al, 2007;Martin, 2010 andMartin et al, 2012). As in the case of the Kivalliq and Hudson suites, many rapakivi granite provinces formed in crust that was intruded about 50-100 myrs previously by equigranular, late syntectonic granite generated by radiogenic heating in thickened crust (e.g., the Ketilidian igneous province: van Breemen et al, 1974;north China craton: Zhang et al, 2007;Fennoscandia: Haapala et al, 1987).…”

Section: Origin Of the Mafic Rocksmentioning

confidence: 99%

The Kivalliq Igneous Suite: Anorogenic bimodal magmatism at 1.75Ga in the western Churchill Province, Canada

Peterson

Scott

LeCheminant

et al. 2015

Precambrian Research

View full text Add to dashboard Cite

Section: Origin Of the Mafic Rocksmentioning

confidence: 99%

The Kivalliq Igneous Suite: Anorogenic bimodal magmatism at 1.75Ga in the western Churchill Province, Canada

Peterson

Scott

LeCheminant

et al. 2015

Precambrian Research

View full text Add to dashboard Cite

“…Additionally, Litchfield pluton compositions plotted on various tectonic discrimination diagrams used for quartz-bearing granitic rocks consistently reveal within-plate tectonic settings (e.g., the Rb vs. Y + Nb diagram of Pearce 1996, not shown). It has been shown that anorogenic alkalic magmatism is common in terranes that have recently experienced an episode of collisional tectonics and thus mark times of tectonic relaxation (Martin et al 2012). This tectonic scenario would fit well with that of south-central Maine in the Carboniferous as the peak period of collisional tectonism in the region (the Acadian orogeny) preceded the intrusion of the Litchfield pluton by about 50 million years (Bradley et al 2000).…”

Section: Regional Tectonic Significancementioning

confidence: 75%

“…significance of these unusual rocks have remained elusive. Silica-undersaturated, nepheline-bearing plutonic rocks are uncommon in the geological record and are generally attributed to small degrees of partial melting of previously metasomatized mantle in anorogenic tectonic settings (e.g., Woolley 2001;Martin et al 2012). Burke et al (2003) have also proposed that the presence of these alkaline plutonic rocks may be indicators of ancient suture zones.…”

mentioning

confidence: 99%

The Litchfield Pluton in South-Central Maine: Carboniferous Alkalic Magmatism in northern New England, USA

West

Bradley

Coish

2016

atgeol

View full text Add to dashboard Cite

The Litchfield pluton is a poorly exposed 7 km 2 composite alkalic intrusive complex that cuts previously deformed and metamorphosed Silurian turbidites in south-central Maine. The pluton includes a variety of alkaline syenites, including the type locality of "litchfieldite, " a coarse-grained cancrinite-, sodalite-, and lepidomelane-bearing nepheline syenite first recognized over 150 years ago and common in many petrologic collections. A new U-Pb zircon age of 321 ± 2 Ma from the nepheline syenite is interpreted to represent the crystallization age of the plutonic complex. A new biotite 40 Ar/ 39 Ar age of 239 ± 1 Ma from the syenite is similar to previously published mica ages from the surrounding country rocks and dates the time of regional cooling in the area below ~ 300°C. Whole-rock chemical analyses of rocks of the Litchfield pluton reveal silica-undersaturated alkaline compositions that are consistent with formation in a within-plate tectonic setting. The age and geochemical characteristics of the alkalic igneous rocks near Litchfield are consistent with a model that invokes the generation of a small volume of alkalic magma beneath south-central Maine during a period of Carboniferous transcurrent tectonism in the northern Appalachian orogen. RÉSUMÉLe pluton de Litchfield est un complexe intrusif alcalin composite de sept kilomètres carrés peu affleurant qui recoupe des turbidites siluriennes précédemment déformées et métamorphisées dans le centre-sud du Maine. Le pluton inclut diverses syénites alcalines, notamment la localité type de la « litchfieldite », une syénite néphélinique renfermant de la cancrinite, de la sodalite et de la lépidomélane à grain grossier identifiée pour la première fois il y a plus de 150 ans et répandue dans maintes collections pétrologiques. Une nouvelle datation U-Pb sur zircon de 321 ± 2 Ma de la syénite néphélinique est interprétée comme une représentation de l'âge de la cristallisation du complexe de roches plutoniques. Une nouvelle datation de la syénite par biotite et The Litchfield pluton in south-central Maine: Carboniferous alkalic magmatism in northern New England, USA nepheline syenite (Fig. 2) that was assigned the name "litchfieldite" by Bayley (1892), is part of a composite alkalic plutonic complex (Barker 1965) that occupies an area of approximately 7 km 2 (Fig. 3). While these unusual rocks have attracted the interest of mineral collectors for over a century and a half, extremely poor exposure has discouraged detailed study; thus the age and tectonic INTRODUCTIONSince the mid-1800s (Jackson 1845; Clarke 1886), the small village of Litchfield in south-central Maine (Fig. 1) has been known as a collecting locality for specimens of cancrinite, sodalite, nepheline, and lepidomelane (Fe-rich biotite). The host rock to these minerals, a coarse-grained of the Litchfield pluton, Barker (1965) suggested that they are associated with the Mesozoic White Mountain magma series. However, limited major element geochemical data are available from these rocks, and ...

show abstract

“…The melting of the lower crust associated to mantle plume action or extensional thinning of the lithosphere associated with stress release-stages and generation of faults or mega-fractures are some of the tectonic models for A-type granites production (e.g. Windley 1991, Frost et al 2001b, Goodge & Vervoort 2006, Martin et al 2012.…”

Section: Discussionmentioning

confidence: 99%

K'Mudku A-type magmatism in the southernmost Guyana Shield, central-north Amazon Craton (Brazil): the case of Pedra do Gavião syenogranite

Souza

Dantas

et al. 2015

Braz. J. Geol.

View full text Add to dashboard Cite

<p>The Mesoproterozoic K'Mudku event (1490 - 1147 Ma) is represented by a britlle-ductile shear belt that cuts across the Paleoproterozoic units in the southernmost Guyana shield, central-north Amazon craton. This event produced mylonitization and cataclasites at low/medium- to high-grade metamorphic, and local within-plate magmatism. In the Amazonas State, Brazil, A-type magmatism chronologically associated to K'Mudku has been reported for the Pedra do Gavião and Samaúma syenogranites. However, the spatial relationship between K´Mudku event and A-type magma generation are not yet adequately clarified in the region. The Pedra do Gavião syenogranite is a high-K alkaline, metaluminous, reduced A-type granite with a post-collisional to within-plate geochemical signature. It has U-Pb zircons crystallization age of 1218 Ma and inherited zircons with ages between 1820 and 1720 Ma, which, together with the Sm-Nd data, suggest melting of Paleoproterozoic basement rocks of the Cauaburi Complex (1810 - 1780 Ma) regional unit. These data demonstrate that the effects of the A-type magmatism associated to the end of the Grenvillian-Sunsas orogeny, reported primarily in the southwestern margin of the Amazon craton, may also be extended for the central-northern part of the Amazon craton. Probably the generation or emplacement mechanisms of A-type magma occurred with some degree of involvement in the final stages of the K´Mudku event. However, this tectonic framework conception still needs more geological and geophysical investigations. Therefore, these news data should instigate to the return of geological research in the region, as well as to debate on the tectonic evolution and A-type granites production during the Ectasian-Stenian period in the central-north Amazon craton.</p>

show abstract

Punctuated anorogenic magmatism

Cited by 16 publications

References 67 publications

The Kivalliq Igneous Suite: Anorogenic bimodal magmatism at 1.75Ga in the western Churchill Province, Canada

The Kivalliq Igneous Suite: Anorogenic bimodal magmatism at 1.75Ga in the western Churchill Province, Canada

The Litchfield Pluton in South-Central Maine: Carboniferous Alkalic Magmatism in northern New England, USA

K'Mudku A-type magmatism in the southernmost Guyana Shield, central-north Amazon Craton (Brazil): the case of Pedra do Gavião syenogranite

Contact Info

Product

Resources

About