Quaternary tectonics in Brazil

Abstract

The concept of tectonic stability has long prevailed for most of the Brazilian platform and, because of this fact, investigation of Quaternary tectonics in Brazil has begun to develop only during the last decade. From the two pioneer groups at the end of the eighties, there are now active groups studying neotectonics in almost all regions of Brazil. A clear demonstration of this progress is the fact that during the 7th Brazilian Symposium on Tectonic Studies, held in Lençóis, Bahia, in May, 1999, of the 141 papers presented more than 20% were related to neotectonics. References to faulting and other geologic features directly related to Quaternary tectonics are increasing and now available for many areas in Brazil. In this paper the geological record of Quaternary tectonics in Brazil is reviewed and a comparison with available geophysical data on stress orientations is presented.

Deep Diversification and Long-Term Persistence in the South American ‘Dry Diagonal’: Integrating Continent-Wide Phylogeography and Distribution Modeling of Geckos

“…Although the exact mechanisms are not clear, events at the Tertiary–Quaternary boundary that significantly remodeled eastern Brazil's landscapes may have confounded the genetic signatures of the earlier isolating events, including vegetation shifts (Werneck et al 2011, in press), and neotectonic activity (Riccomini and Assumpção 1999). We suggest that the less dramatic differentiation between Cerrado and Caatinga lineages could be due to a combination of more recent divergence and gene flow, and represent a possible example of ecological or sympatric speciation (Vanzolini 1976).…”

Moho map of South America from receiver functions and surface waves

“…These processes continued through the Tertiary [de Almeida et al, 2000;Beurlen, 1970] and there are indications for current tectonic activity [Riccomini and Assumpção, 1999].…”

“…The tectonic processes responsible for the current landscape were most active during the Lower Cretaceous. These processes continued through the Tertiary [ de Almeida et al , 2000; Beurlen , 1970] and there are indications for current tectonic activity [ Riccomini and Assumpção , 1999]. …”

Passive margins getting squeezed in the mantle convection vice

“…Lastly, tectonic inversion affects many margins (Figure ). Again, examples are found in Brazil [ Gomes Sant'Anna et al ., ; Riccomini and Assumpcao , ; Cobbold et al ., ; Cogné et al ., , ] and Patagonia [ Rodriguez and Littke , ], in the British Isles [ Andersen and Boldreel , ; Lundin and Doré , ; Smallwood , ] and in the North Atlantic [ Doré et al ., ], Norway [ Brekke , ], West Africa [ Hudec and Jackson , ; Jackson et al ., ; Briggs et al ., ], Moroccan Meseta [ Ghorbal et al ., ], India [ Gunnell and Fleitout , ], Iberia [ Masson et al ., ; Peron‐Pinvidic et al ., ], and Australia [ Hillis et al ., ; Bishop and Goldrick , ]. Here we refer to tectonic inversion when former normal faults are tectonically inverted and unambiguously reveal compression.…”