Roberto Siqueira

Université de Toulouse

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Ricardo I.F. Trindade

Universidade de São Paulo

Antomat Avelino Macêdo

Alisson Oliveira

Manoel S. D’Agrella-Filho

Universidade de São Paulo

Igor Ivory Gil Pacca

Universidade de São Paulo

Márcia Ernesto

Universidade de São Paulo

María Irene Bartolomeu Raposo

Universidade de São Paulo

Thelma S. Berquó

Concordia College - Minnesota

Gaétan Moloto-A-Kenguemba

University of Bangui

C.F. Ponte Neto

Universidade de São Paulo

Cooperative Institutions

Universidade de São Paulo

Centre National de la Recherche Scientifique

Institut des Sciences de la Terre

Instituto de Geofísica y Astronomía

Instituto de Geociencias

Université de Toulouse

Institut de Recherche pour le Développement

Sociedade Brasileira de Geofísica

Université Toulouse III - Paul Sabatier

Institut des Sciences de la Terre d'Orléans

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Paleomagnetic Constraints on the Rodinia Supercontinent: Implications for its Neoproterozoic Break-up and the Formation of Gondwana

International Geology Review (1998)

Manoel S. D’Agrella-Filho Ricardo I.F. Trindade Roberto Siqueira Cosme F. Ponte-Neto Igor Ivory Gil Pacca

An interpretation of available paleomagnetic data from the Laurentia, Congo-Sao Francisco, Kalahari, and Amazonia cratons favors the hypothesis that these units were juxtaposed in a supercontinent by 1000 Ma. This supercontinent is similar to Hoffman's (1991) Rodinia, except for the Kalahari craton, whose 1300 to 1000 Ma Namaqua-Natal mobile belt is now juxtaposed against the correlated 1300 to 1000 Ma Grenville belt in eastern Laurentia, Our model suggests that a continuous 1300 to 1000 Ma orogenic belt, formed by the Grenville, Sunsas, Kibaride-Irumide-Lurio, Namaqua-Natal, and Dronning Maud Land-Coats Land belts, represents the suture zone between the Amazonia, Congo-Sao Francisco, Kalahari-Grunehogna, and Laurentia blocks. The formation of western Gondwana (from our Rodinia supercontinent) may be accomplished by the closure of the large Mozambique Ocean and the more restricted Adamastor Ocean, combined with some counterclockwise rotation of the Congo-Sao Francisco craton. Rotation of the Congo-Sao Francisco craton can explain the observed oblique convergence and wrench tectonics of Pan African-Brasiliano mobile belts that encircle this craton. The model is also consistent with the synchroneity between the Rodinia break-up and the assembly of Gondwana, as suggested by several authors (Laurentia began to separate from Rodinia at ∼625 Ma or later).

Rodinia

Supercontinent

Laurentia

Laurasia

10.1080/00206819809465205

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Citations (36)

Structure and petrology of Pan-African nepheline syenites from the South West Cameroon; Implications for their emplacement mode, petrogenesis and geodynamic significance

Journal of African Earth Sciences (2013)

Nsifa Nkonguin Emmanuel Rigobert Tchameni Anne Nédélec Roberto Siqueira André Pouclet

Nepheline syenite

Nepheline

Petrogenesis

Amphibole

10.1016/j.jafrearsci.2013.07.008

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Citations (38)

Paleomagnetic constraints on the neoproterozoic Rodinia: implications its break-up and the formation of Gondwana

Abstracts (1997)

Manoel Souza D'Agrella Filho C.F. Ponte Neto Ricardo I.F. Trindade Roberto Siqueira Igor Ivory Gil Pacca

Rodinia

Supercontinent

Source

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Citations (0)

A late Neoproterozoic paleomagnetic pole for the Congo craton: Tectonic setting, paleomagnetism and geochronology of the Nola dike swarm (Central African Republic)

Precambrian Research (2008)

Gaétan Moloto-A-Kenguemba Ricardo I.F. Trindade Patrick Monié Anne Nédélec Roberto Siqueira

Dike

Apparent polar wander

Geochronology

Rodinia

Laurentia

10.1016/j.precamres.2008.05.005

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Citations (56)

The effect of magnetic anisotropy on paleomagnetic directions in high-grade metamorphic rocks from the Juiz de Fora Complex, SE Brazil

Earth and Planetary Science Letters (2003)

María Irene Bartolomeu Raposo Manoel S. D’Agrella-Filho Roberto Siqueira

Rock magnetism

10.1016/s0012-821x(03)00065-7

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Citations (25)

Using a 'speedy' unspiked K–Ar methodology to investigate age patterns in giant mafic dike swarms

Figshare (2021)

Alisson Oliveira Roberto Siqueira Antomat Avelino Macêdo

Table S3. Information on five unknown samples and one GA1550 standard measurement

Dike

10.6084/m9.figshare.14510523

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Citations (1)

The tourmaline-bearing granite pluton of Bodmin (Cornwall, UK): magnetic fabric study and regional inference

Journal of the Geological Society (2006)

J. L. Bouchez Thierry Mintsa Mi Nguema Lionel Esteban Roberto Siqueira R.C. Scrivener

The magnetic fabrics and microstructures of the Variscan granite pluton of Bodmin (Cornwall) have been studied. Its low susceptibility magnitude, consistent with its lack of magnetite, comes from biotite and tourmaline. As the magneto-crystalline behaviour of tourmaline is ‘inverse’ compared with that of the phyllosilicates, the magnetic fabric was remeasured after heating the specimens to enhance the biotite magnetic signal by the growth of mimetic magnetite. The roughly similar magnetic fabrics before and after heating demonstrate that the effect of tourmaline is not important as long as the tourmaline content does not exceed that of the phyllosilicates. Regionally, this study reveals a well-defined NNW trend of the magnetic lineations with opposite plunges on each side of a separation line crossing the pluton centre. This pattern, very similar to that documented in the nearby Carnmenellis pluton, is ascribed to unroofing during emplacement. It agrees with the late to post-magmatic NW stretch that characterizes the Devonian to Carboniferous formations located to the north of this region, the thrust-and-fold structure of which is attributed to southward compression. We conclude that syntectonic emplacement may have characterized the whole Cornubian batholith at the very end of the Variscan orogeny in Cornwall.

Tourmaline

10.1144/0016-764905-104

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Citations (19)

Using a 'speedy' unspiked K–Ar methodology to investigate age patterns in giant mafic dike swarms

Figshare (2021)

Alisson Oliveira Roberto Siqueira Antomat Avelino Macêdo

Table S1. Weighted average age for argon measurements

Dike

10.6084/m9.figshare.14510520

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Citations (0)