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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Towards Columbia: Paleomagnetism of 1980-1960 Ma Surumu volcanic rocks, Northern Amazonian Craton

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Author(s):
Bispo-Santos, Franklin [1] ; D'Agrella-Filho, Manoel S. [1] ; Janikian, Liliane [2] ; Reis, Nelson J. [3] ; Trindade, Ricardo I. F. [1] ; Reis, Maria Anna A. A. [1]
Total Authors: 6
Affiliation:
[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil
[2] Univ Catolica Santos, BR-11015002 Santos, SP - Brazil
[3] Manaus Agcy, Geol Survey Brazil, Manaus, Amazonas - Brazil
Total Affiliations: 3
Document type: Journal article
Source: Precambrian Research; v. 244, n. SI, p. 123-138, MAY 2014.
Web of Science Citations: 19
Abstract

We present a paleomagnetic study on the well-dated 1980-1960 Ma (U-Pb) volcanic rocks from the Surumu Group, northern Roraima State (Amazonian Craton). After thermal and AF demagnetization, characteristic northwestern remanent magnetization (ChRM) directions with downward inclinations were isolated (mean: Dm =298.6 degrees, I-m =39.4 degrees, alpha(95) = 10.1 degrees, N = 20 degrees, K=11.4 degrees), which yielded a paleomagnetic pole (SG) located at 234.8 degrees E, 27.4 degrees N (A(95)= 9.8 degrees). Magnetic mineralogy experiments show that ChRM is carried by high-Hc, and high-unblocking temperature Ti-poor titanomagnetite and/or hematite. The well-dated pole SG contributes to better define the apparent polar wander (APW) path for the Guiana Shield during the Paleoproterozoic (2070-1960 Ma). Comparison of the Amazonian and West African Craton's APW paths for the same time interval suggests that these cratonic blocks were linked together at about 1980-1960 Ma ago in a paleogeography along which the Guni (Guiana Shield) and Sassandra (West Africa Craton) shear zones were aligned as previously proposed. (C) 2013 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 12/50327-3 - The Amazonian Craton and the supercontinent Columbia: paleogeographic implications based on the paleomagnetic study of Paleo-mesoproterozoic geological units
Grantee:Franklin Bispo dos Santos
Support Opportunities: Scholarships in Brazil - Post-Doctoral
FAPESP's process: 11/50887-6 - Paleomagnetism of proterozoic geological units from the Amazonian Craton, and its participation in the Columbia, Rodinia, and Gondwana supercontinents
Grantee:Manoel Souza D'Agrella Filho
Support Opportunities: Regular Research Grants