| Full text | |
| Author(s): |
Salminen, J.
;
Oliveira, E. P.
;
Piispa, E. J.
;
Smirnov, A. V.
;
Trindade, R. I. F.
Total Authors: 5
|
| Document type: | Journal article |
| Source: | Precambrian Research; v. 329, p. 16-pg., 2019-08-01. |
| Abstract | |
The original connections of Archean cratons are becoming traceable due to an increasing amount of paleomagnetic data and refined magmatic barcodes. The Ilaua block of the northern Sao Francisco craton may represent a fragment of a major Archean craton. Here, we report new paleomagnetic data from the 2.62 Ga-Vaud tholeiitic mafic dyke swarm of the Uatia block in the northern Sao Francisco craton, Eastern Brazil. Our paleomagnetic results confirm the earlier results for these units, but our interpretation differs. We suggest that the obtained characteristic remanent magnetization for the 2.62 Ga swarm is of primary origin, supported by a provisionally-positive baked contact test. The corresponding paleomagnetic pole (25.2 degrees N, 330.5 degrees E, A(95) = 8.1 degrees, N = 20) takes the present northern part of the Sao Francisco craton to moderate latitudes. Based on the comparison of the paleolatitudes of cratons with high-quality paleomagnetic data and magmatic barcodes, we suggest that the northern part of the Sao Francisco craton could have been part of the proposed Supervaalbara supercraton during the Archean. Supervaalbara is proposed as including (but not limited to) the part of the Sao Francisco craton as well as the Superior, Wyoming, Kola + Karelia, Zimbabwe, Kaapvaal, Tanzania, Yilgarn, and Pilbara cratons. (AU) | |
| FAPESP's process: | 12/15824-6 - Evolution of archaean terranes of the São Francisco Craton and the Borborema Province, Brazil: global environmental and geodynamic implications |
| Grantee: | Elson Paiva de Oliveira |
| Support Opportunities: | Research Projects - Thematic Grants |