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O Superterreno Pernambuco Alagoas (PEAL), previamente designado de Maciço e/ou Terreno, é o segmento tectônico identificado imediatamente ao sul do lineamento Pernambuco. Apresenta uma área de cerca de 60.000km2, forma triangular, com a base entre o Recife e imediações de Maceió, e com vértice nas imediações de Santa Cruz, oeste de Pernambuco. Sua composição é extremamente variada, com terrenos de alto grau, arqueanos, paleoproterozoicos, eo-neoproterozoicos e tratos metavulcanossedimentares neoproterozoicos (faixas supracrustais). Estes terrenos são cortados por granitoides neoproterozoicos diversos, incluindo batólitos lineares de grandes dimensões, por stocks e batólitos menores relativamente isolados. Localmente, na sua parte centro sudoeste, foi recentemente reconhecido magmatismo granítico de arco (Ediacarano em idade). O comportamento geotectônico deste amplo superterreno- posicionado entre as faixas orogênicas da Zona Transversal e aquelas da periferia norte do craton do São Francisco (parte do o chamado “domínio meridional” da Borborema) tem sido bastante estudado, discutido e nomeado, mas é de conhecimento geral ainda perfuntório. Apresenta uma trama litoestrutural complexa, e pode ser preliminarmente dividido, para fins expositivos em três porções distintas: porção ocidental (com muitos relictos arqueanos e paleoproterozoicos), porção central (embasamento paleoproterozóico retrabalhado e supracrustais neoproterozoicas) e porção mais oriental, com exposição de um longo e linear batólito longitudinal (longitudinal à costa atlântica) e algumas supracrustais, distintas daquelas anteriormente citadas.

The Tonian Cariris Velhos event was studied in the area around Afogados da Ingazeira town, Pernambuco State, Northeast Brazil, which is situated within the Alto Pajeu terrane, a Tonian-Ediacaran composite domain of the Borborema Province. The exposed rocks belong to the Sao Caetano Complex, which is formed of biotite-muscovite paragneisses and quartz-feldspathic gneisses, derived from arkosic or felsic volcanic protoliths, with marble and quartzite intercalations. The deformation started with a D1/D2 thrusting episode, when metamorphism ranged from greenschist to amphibolite facies, and was accompanied by emplacement of orthogneiss sheets. The subsequent episode, the D3 phase, had an extensional character and was marked by intrusion of small metadiorite dikes, which were strongly transposed by the D4 phase, a new episode of transcurrent deformation. The main structure of the D4 phase is the Afogados da Ingazeira shear zone (ZCAI), which Ediacaran age was well constrained by the associated Solidao granite, dating from 574 ± 54 Ma. A geochemical study of the metasedimentary rocks shows that the protoliths of the paragneisses located in the southeastern part of the ZCAI are greywackes, whereas those of the northwestern part are greywackes, lithic sandstones and arkoses, although the REE patterns of these samples normalized to NASC (North American Shale Composite) show minor differences between them. These metasedimentary rocks have geochemical signatures and patterns of synorogenic sediments compatible with island and continental arc sources. The geochemical patterns of the orthogneisses are also consistent with a magmatic arc environment, the same conclusion reached by other authors with respect to the metavolcanic rocks of the Alto Pajeu terrane. The occurrence of the pre-transcurrent D3 extensional episode suggests that the D1/D2 thrusting deformation and associated metamorphism may be related to orogenic processes, pointing to the existence of the Cariris Velhos orogeny.

U-Pb and Pb-evaporation zircon ages, together with whole-rock Sm-Nd and Pb-Pb data, are used to unravel the tectonic evolution of the northern segment of the Itabuna-Salvador-Curaca Orogen, northeastern Sao Francisco Craton. The results of this geochronologic study indicate that oceanic crust and island arc sequences accreted at 3.3 Ga, forming the Mundo Novo Greenstone Belt, and that between 2.2 - 2.12 Ga the Rio Itapicuru and Rio Capim Greenstone Belts were formed in a similar fashion. Age data and Nd isotopes also suggest that Andean-type continental margins are likely to have formed in the span of time 3.08 - 2.98 Ga, giving rise to the TTG belts of Retirolândia and Jacurici river, and to the Caraiba Complex between 2.69 - 2.63 Ga. Around 2109 Ma, continent-continent collision closed the Rio Itapicuru volcano-sedimentary basin, as inferred from the syntectonic emplacement of the Itareru Tonalite between the Rio Itapicuru Greenstone Belt to the east and the banded gneisses of the Serrinha Block to the west. This collision culminated in a major shift from frontal or oblique convergence to orogen-parallel block-escape about 2084 Ma ago and continued at least till 2039 Ma. During this event several elongated granitic and syenitic bodies were emplaced in the continental crust. The Itiuba Syenite, dated at 2084 Ma and stretching over 150 km east of the Caraiba Complex, is an example of one of these intrusive bodies.