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The Borborema Province in NE Brazil is assumed to have been formed by Cryogenian-Ediacaran convergent events during the assembly of western Gondwana. Among the many geological markers of such episodes, the granitic record is widespread, representing the best testimony of the Brasiliano-Pan African Orogeny that took place between 800 and 500 Ma. Several granitic batholiths and stocks are interpreted as root remnants of arc edifices that grew during the consumption of large tracts of oceanic crust, such as the Goiás-Pharusian and Transordestino-Central África realms. Most of them share geochemical signatures that are typical for subduction-related magmas, such as enrichment in large-ion lithophile elements, aligned with depletion in high-field strength elements, including negative anomalies in Nb, Ta, P, and Ti, as well as systematic plots consistent with convergent-related settings in classical tectonic discrimination diagrams. The older record is represented by the Lagoa Caiçara unit (ca. 880-800 Ma) of the Santa Quitéria magmatic arc of the Northern Subprovince, interpreted as relics of an intra-oceanic setting, responsible for lithospheric growth in the region. A subsequent magmatic episode is marked by the injection ca. 650-620 Ma cordilleran and peraluminous magmas that formed a large set of batholiths and stocks in the Santa Quitéria and Conceição (Transversal Subprovince) magmatic arcs, as well those related to the Pernambuco-Alagoas Terrane and Sergipano Belt in the Southern Subprovince. Rocks crystallized in this age interval share similarities with those of the calc-alkalic and alkali-calcic series, interpreted to have been emplaced in the continental crust via upper mantle melting and subsequent crustal contamination. Finally, rocks aged between ca. 620-550 Ma are widespread and represent high-K, meta-to peraluminous and alkali-calcic precursor magmas, that also share geochemical similarities with S-type granites (crustal anatexis), being interpreted as syn-collisional with respect to the final assembly of Gondwana. The final framework of the Borborema Province is marked by extrusion tectonics that is materialized by the complex network of shear zones deforming the previous formed granites and injecting of non-subduction related melts. Although there is a lack of consensus regarding the assembly of the province during the Neoproterozoic, we suggest that accretionary-collisional events played a major role, as testified by the geochemical-isotopic signature of the arc-related granites, in addition to a number of structural, geophysical, and geological mapping data published in the recent years. • Neoproterozoic magmatic arcs of the Borborema Province are revisited. • Geochemical and isotopic data of the subduction-related granites are evaluated. • The nature of accretionary and collisional events is discussed. [ABSTRACT FROM AUTHOR]

Early Neoproterozoic (1000-920 Ma) rocks related to the Cariris Velhos event in the central Borborema Province have been linked to either continental rifting or accretionary-collisional orogenesis. The Serra do Jatobá Suite is located in the southwestern part of the Alto Pajeú Terrane along with coeval metasedimentary sequences and Ediacaran granites. This suite is composed of alkali-calcic, meta-to peraluminous granodiorites to monzogranites that share similarities with both ferroan- and magnesian granite series. Chondrite normalized REE (Rare Earth Elements) patterns are moderately fractionated with pronounced negative Eu anomalies. Incompatible element spidergrams show a negative Nb–Ta anomaly, similar to those observed in Cordilleran-type granites. U–Pb zircon data constrain the crystallization ages at around 1000 Ma, whereas calculated εNd(t) values range between −1.74 and −0.94. Obtained T DM model ages range from 1.76 to 1.54 Ga, which corresponds with source ages for the Cariris Velhos magmatic rocks. Our findings suggest that subduction took place in the early Neoproterozoic in the Borborema Province, pointing to an accretionary nature for the Cariris Velhos event. • Early Neoproterozoic magmatism in western Gondwana. • Magmatic arc-related rocks constrains the early phases of the Cariris Velhos Orogeny. • Ca. 1000 Ma growth and reworking recorded in the central Borborema Province. [ABSTRACT FROM AUTHOR]

The Cariris Velhos event (ca. 1000-920 Ma) is a significant marker in the early Neoproterozoic lithospheric record of the Borborema Province in NE Brazil. Despite its importance, the nature of this event remains unresolved having been linked to either continental rifting or accretionary-collisional orogeny. In this study, we support a compressive setting for the Cariris Velhos event based on compiled geochemical and isotopic data (Sm–Nd and Lu–Hf) from metagranitic rocks in the Alto Pajeú Terrane (central Borborema) and in the Pernambuco-Alagoas Super Terrane, as well as in the Riacho do Pontal and Sergipano fold belts (Southern Borborema). Geochemistry of these rocks share similarities with calcic to alkali-calcic and ferroan magmas, along with some Cordilleran magnesian members. They also correspond to meta-to peraluminous I- and S-type granitic rocks. Trace element distribution on spider diagrams reveals negative anomalies of HFSE (high field strength elements) such as Nb and Ta, which are typically associated with subduction-related settings. Additionally, chondrite normalized REE (rare-earth element) diagrams indicate mixing of both crustal and mantle material. Tectonic discriminant diagrams using elements with low mobility supports the hypothesis of a continental margin subduction-related setting. Calculated ε Nd and ε Hf values vary from negative to slightly positive, suggesting contributions from juvenile inputs and reworking of Meso-Paleoproterozoic crust, as indicated by the associated T DM model ages. Although the nature of the Cariris Velhos event requires further investigation, we suggest that, at least partially, it corresponded to an orogenic episode that might have occurred concurrently with continental break-up, similar to modern continental arc-retro arc foreland settings. • Early Neoproterozoic magmatism in the Borborema Province is revisited. • The nature of the Cariris Velhos event is discussed. • A complex accretionary setting coeval to anorogenic magmatism is considered. • Subduction-related processes took place in the 1000-920 Ma age interval. [ABSTRACT FROM AUTHOR]

Combined geophysical and structural data from the Transversal Subprovince of the Borborema Province (NE Brazil) highlight the internal structure of, and interrelationships between, the constituent terranes. Radiometric and magnetic maps show distinctive signatures for the Archean-Paleoproterozoic Alto Moxotó and Meso-to Neoproterozoic Alto Pajeú and Pernambuco-Alagoas terranes. Mapped radiometric and first and second order magnetic lineaments, associated with Euler deconvolution, enable correlation between geophysical data and major structures. In addition to early related deformation of the Alto Moxotó Terrane, combined analysis of late transposition foliations, lineations and kinematic criteria reveal a complex structural evolution marked by two distinct assembly stages. The first phase is characterized by thrust tectonics with top-to-the-south vergence, resulting in the juxtaposition of the allochtonous Alto Pajeú Terrane with the structurally underlying Alto Moxotó Terrane. The terrane boundary is delineated by the Serra de Jabitacá Shear Zone, which is associated with low dipping collisional granitic sheets and ca. 1.0 Ga mafic-ultramafic rocks interpreted as obtudcted ophiolite remnants. Later strike-slip movements strongly folded and obliterated thrust-related markers, and the continental scale E-W Pernambuco Lineament is interpreted as the result of lateral assembly between the composite Alto Pajeú-Alto Moxotó terranes and the Pernambuco-Alagoas Terrane during the metamorphic peak of the Brasiliano orogeny. Evolution of the Borborema Province reflects accretionary processes during the assembly of Western Gondwana. [ABSTRACT FROM AUTHOR]

The deformation processes (e.g. accretionary or intraplate) occurring within the Borborema Province have been widely discussed, however the eastern part of the central subprovince lacks further investigation in such aspect. In this contribution, we present integrated airborne gamma ray and magnetometric geophysical data, as well as meso- and microstructural markers of the Archean-Paleoproterozoic Alto Moxotó and Neoproterozoic Rio Capibaribe terrains (central Borborema Province), providing evidence for hidden accretionary episodes in the region. Fourteen radiometric and ten magnetic domains were described and fitted with most of the geological units and mapped structures, suggesting geological contrasts between the studied terrains. For instance, the Alto Moxotó terrain presents high-to-medium eTh and eU radiometric signatures, spatially distributed along folded geometry, whereas the lithospheric record of the Rio Capibaribe terrain is characterized by K (%) enrichment and a dominant NE-SW sheared crust. In addition, the obtained Euler solutions show good correlations with the main structures and delineated shallow to intermediate sources of the Congo-Cruzeiro do Nordeste strike-slip shear zone system, the proposed structural boundary. This large set of shear zones are characterized by large mylonitic corridors with characteristic vertical foliation planes with moderately-plunging mineral lineations. Associated microstructures include bulging, subgrain rotation and recrystallization that, in association with the well-developed S–C fabrics and myrmekites indicate deformation at moderate temperature values (∼400–500 °C). Also, conspicuous fracture networks seen in plagioclase grains demonstrate that deformation also took place at the later developed brittle-ductile transition. Hence, the described contrasting rock ages and nature, geophysical signatures and deformational patterns is herein interpreted as the result of crustal agglutination during the Neoproterozoic, in which the Congo-Cruzeiro do Nordeste shear zone system would represent relics of a terrane boundary developed during the assembly of western Gondwana. • Airborne geophysical data constrain the Rio Capibaribe and Alto Moxotó terrains crustal boundary. • The Congo-Cruzeiro do Nordeste shear zone system operated at the ca. 500-400 °C temperature interval. • Accretion tectonics is the likely mechanism that operated in this portion of western Gondwana. [ABSTRACT FROM AUTHOR]

The Cariris Velhos Belt is an unique domain of the Borborema Province, Brazil, because it presents magmatic and metamorphic lithotectonic associations spanning all the Neoproterozoic. In this study, we investigate the main sources of its major supracrustal sequence (i.e. São Caetano Complex) as well as genetic aspects of a later intrusive granitic body, the São Pedro Stock. Detrital U-Pb zircon determinations for the supracrustal rocks are characterized by a major peak in the range of 1.0-0.9 Ga, with maximum deposition age at around 0.86 Ga. Minor components are aged at 1.8-1.6 Ga and 2.5 Ga. The Nd isotopic composition for this unit suggest crustal reworking of Meso-to Paleoproterozoic sources as well as inheritance of juvenile mantle material. Whole-rock geochemical data points out to derivation from magmatic arc-related andesites and rhyolites as well as foreland material, and we interpret this sequence as remnant of the Cariris Velhos (1.0-0.9 Ga) post-orogenic basin. The São Pedro Stock corresponds to a mostly isotropic intrusion of dominantly granitic composition. U-Pb zircon data from a monzogranitic and a tonalitic samples suggest crystallization ages of ca. 615 ± 02 Ma and 596 ± 22 Ma, respectively. Zircon crystals with ages of ca. 981 ± 29 Ma are interpreted as inherited crystals. Sm-Nd isotopic behavior is similar from samples of the São Caetano Complex, whereas overall geochemistry suggests crystallization from high-K calc-alkaline and peraluminous magmas, in addition to trace-element distribution compatible with Cordilleran granites. It is proposed that the São Pedro stock were formed in a modern-style subduction zone in later stages of the Brasiliano-Pan African orogeny (0.6-0.5 Ga). Accordingly, we conclude that systematic subduction-accretion episodes took place in this part of West Gondwana from early to late Neoproterozoic times. • Isotopic data reveals Neoproterozoic accretion in the central Borborema Province. • Rocks of the São Caetano Complex were derived from an exhumed Tonian arc. • The intrusive São Pedro Stock represents remnants of an Ediacaran orogenic edificie. • Systematic accretion-subduction episodes took place in this portion of West Gondwana. [ABSTRACT FROM AUTHOR]

Abstract The Sergipano Fold Belt is a Neoproterozoic orogen exposed in the southern Borborema Province (Northeast Brazil), which is interpreted as the result of the oblique convergence process between the São Francisco-Congo block and smaller crustal fragments. The Nicolau-Campo Grande Complex is the metavolcanic-sedimentary portion of the Jirau do Ponciano Dome, an important basement inlier within this collisional belt. Whole-rock-geochemical major and trace-element data of major and trace elements from the metavolcanic rocks of the Nicolau-Campo Grande Complex indicate basaltic-andesite, andesitic, rhyodacitic, and rhyolitic compositions. Rare earth element and trace elements show the typical signature of magmatic arc rocks with negative Nb, Ta, P, and Ti anomalies. New U-Pb zircon data from amphibolite and hornblende-biotite paragneiss samples from the complex confirm the existence of a Paleoproterozoic zircon population of a Paleoproterozoic age of approximately ca. 2054 Ma with Archean inheritance ranging in age between 2779 and 3324 Ma. A maximum sedimentation age of 2028 Ma is constrained by the youngest zircon grain in the hornblende-biotite paragneiss. Zircon U-Pb data from the metarhyolite and rhyodacites indicate Paleoproterozoic ages of ca. 2061 and 2074 Ma, respectively, interpreted as their crystallization age. Nd isotopic data in the metarhyolite and rhyodacites indicate Nd T DM ages between 2.54 and 3.07 Ga and 87Sr/86Sr (2061Ma) values from 0.71396 to 0.72351. Based on these data, we suggest that the probable source area of the metavolcanic-sedimentary complex is a Paleoproterozoic magmatic arc that was exhumed and covered by the paleobasins of the Macururé Domain in the northeast portion of the Sergipano Fold Belt. Highlights • Isotope geochemistry is used to understand the source of supracrustal rocks of the Jirau do Ponciano Dome, Borborema Province. • Volcanic magmatism occurred at around c. 2.0 Ga, coeval to detrital zircon major population (ca. 2054 Ma), with inheritance of Archean crust. • Studied rocks are derived from an exhumed Paleoproterozoic magmatic arc covered by paleobasins that comprises this portion of the Western Gondwana. [ABSTRACT FROM AUTHOR]