A review of 3.66 to 2.77 Ga crustal differentiation in the northern São Francisco Craton, Brazil

ABSTRACT The Archaean crustal evolution of the northern São Francisco Craton (SFC) reveals significant similarity with Kaapvaal-Zimbabwe and Pilbara, cratons, especially before 3.0 Ga. Likewise, compiled geochronological and Nd-Sr-Hf isotope data suggest that the Archaean blocks of the northern part of SFC (e.g. Gavião, Uauá and Serrinha) shared similar crustal evolution since 3.15 Ga. The 3.42–3.35 Ga TTGs of the southern and western Gavião Block have negative and slightly positive ɛNd(t) and ɛHf(t) values and TDM(Hf) ages between 3.50 and 3.90 Ga, indicating that they were produced by partial melting of Eoarchaean to Palaeoarchaean crust, with minor mantle sources. The ca. 3.30 Ga high-silica plutonic-volcanic system, which is related to intraplate magmatism and intracrustal differentiation processes, would represent processes of continental rifting and break-up. In the northern Gavião Block, the 3.64 Ga migmatite-gneiss paleosomes with negative ɛHf(t), 176Hf/177Hf ratio between 0.2802 and 0.2805 and TDM(Hf) ages between 3.75 and 4.15 Ga of the Mairi Complex represent the oldest dated rocks of the whole São Francisco Craton, suggesting late Hadean and Eoarchaean sources. The 3.15 and 3.00 Ga rocks of the Serrinha Block have positive ɛNd(t) values, suggesting a predominant juvenile source. Likewise, coeval 3.15 and 3.00 Ga Uauá Block rock assemblage has slightly positive to negative ɛNd(t) values, which indicate mixing of crustal and juvenile sources. The 2.90 to 2.77 Ga period in the SFC is characterized by pervasive crustal anatexis with high-K granite generation, similar to Kaapvaal and Pilbara cratons. Therefore, Archaean migmatite-gneiss terrains recorded four crustal differentiation intervals (e.g. 3.66–3.51, 3.45–3.30, 3.15–3.00 and 2.90–2.77 Ga) in the São Francisco Craton.


Introduction
The Earth's oldest cratons represent the relicts of Eoarchaean to Palaeoarchaean continental crust formed by tonalite-trondhjemite-granodiorite (TTG) series associated with Na-rich granites (e.g. Zeh et al. 2009;Kemp et al. 2015;Petersson et al. 2019;Chaudhuri 2020). In this context, the major question is how early plate tectonics and crustal generation processes operated (e.g. Petersson et al. 2020;Gardiner et al. 2021). The early Archaean crustal fragments have been well studied for decades (e.g. Condie 1989;Teixeira et al. 2000;Moyen et al. 2021). Some of the most well-known cratons are the Kaapvaal and Zimbabwe cratons, in southern Africa, and the Pilbara Craton, in western Australia (e.g. Smithies et al. 2007;Zeh et al. 2009;Jelsma et al. 2021;Mühlberg et al. 2021) that, similarly to the São Francisco Craton, host rocks with ages between 3.45 Ga and 3.65 Ga. In South America, the São Francisco Craton (Almeida et al. 1981) is one of the largest cratonic areas and its northern portion contains the ca. 3.66 Ga TTG orthogneisses related to early crustal differentiation, which are the oldest dated rocks in the continent (e.g. Oliveira et al. 2020;Moreira et al. 2022;Santos et al. 2022).
Despite a long history of geologic research, there are still uncertainties about the sources and crustal mechanisms that contributed to the evolution of the São Francisco Craton (SFC) throughout Archaean times (e.g. Martin et al. 1997;Guitreau et al. 2012;Lana et al. 2013;Teixeira et al. 2017;Oliveira et al. 2020). Thus, more work is needed to understand the timing, mechanisms and conditions of the 3.66 to 2.77 Ga geological processes, by studying the exposed Archaean rocks formed at different crustal levels, such as: (i) high-grade metamorphic terranes of TTGs, which represent Archaean midcontinental crust; (ii) low-grade granite-greenstone belts related to Archaean upper continental crust and (iii) medium-high-grade metamorphic rocks, reequilibrated at amphibolite-to granulite facies. Therefore, to obtain a better understanding of the northern SFC crustal evolution zircon U-Pb and Hf, Nd, and Sr isotope data available in the literature from 1985 to 2021 were compiled. This allowed us to compare the nature of the three blocks in which Eo to Mesoarchaean rocks crop out (i.e. Gavião, Serrinha and Uauá blocks). In order to place the SFC in a global context of Archaean crustal evolution, a comparison between São Francisco (Brazil), Pilbara (western Australia), Kaapvaal, and Zimbabwe (southern Africa) cratons was established, which have similarities that will be further discussed.

Data compilation
A comprehensive literature review was undertaken in order to identify geochronological and isotopic studies performed in the Eo-to Mesoarchaean rocks of the northern SFC. The systematic quantitative approach presented by Pickering and Byrne (2014) was utilized since this method is reproducible and explicit and presents few biases in comparison with traditional review systematics (De Brito and Evers 2016). To make sure that relevant papers were not missed, different databases such as Science Direct, Web of Science, Periódicos CAPES, Scopus, Springer Link, and ProQuest were systematically searched. Publications such as book chapters, conference proceedings and reports, peer-reviewed articles, doctoral dissertations, and masters theses written in English, French, and Portuguese were included. As a result, 23 references about the São Francisco Craton published over more than three decades (between 1985 and 2021) were compiled, including a total of 284 Hf, Nd, and Sr isotope data. The main geochronological and isotope data and their references are presented in supplementary materials 1 to 3. Furthermore, Hf isotope data of the SFC were plotted together with data from Pilbara (western Australia), Kaapvaal, and Zimbabwe cratons (southern Africa) in time-integrated diagrams, in order to build a global appraisal of Eo to Mesoarchaean crustal growth intervals.

Gavião block (GB)
The GB comprises a variety of TTGs, migmatites, geisses and granites as well as greenstone belts (e.g. Barbosa et al. 2012Barbosa et al. , 2020a. Specifically, older TTG orthogneisses were dated between 3654 and 3260 and 3180-3000 Ma (e.g. Nutman and Cordani 1993;Martin et al. 1997;Peucat et al. 2002;Dantas et al. 2013;Oliveira et al. 2020;Barbosa et al. 2020a;Moreira et al. 2022) (Figures 2, 3). Most of these TTGs and migmatites are associated with older metavolcanic-sedimentary sequences that occur scattered within the block. An age of 4.15 Ga was obtained from a detrital zircon of the Ibitira-Ubiraçaba metavolcanic-sedimentary sequence within the southern GB, which can be considered as indirect evidence of Hadean crust in the area (e.g. Paquette et al. 2015). Since the GB represents most of the area of the northern SFC, as shown in Figure 1, we present through this article a geographical subdivision, into Northern, Southern, and Western Gavião Block. This eases the orientation of the reader within the craton, despite the isotope data showing that the GB was a single tectonic unit during Archaean times.

Northern Gavião block
This part of the GB is bounded to the east by the northern portion of the Contendas-Jacobina Lineament (CJL) (Sabaté et al. 1990) and to the north by the Neoproterozoic Riacho do Pontal, Rio Preto, and Sergipano Belts. According to Barbosa et al. (2012), the Archaean-Palaeoproterozoic rocks of the northernmost GB are, largely, covered by Meso-andx-Neoproterozoic meta-sedimentary rocks. The northern GB is constituted of TTGs and orthogneisses, meta-sedimentary units, greenstone belts, and metavolcano-sedimentary sequences dated between 3.65 and 2.50 Ga (e.g. Peucat et al. 2002;Teles et al. 2015;Oliveira et al. 2020;Moreira et al. 2022) (Figure 3(a)) (Supplementary material and references therein). In the northernmost part of the GB, gneisses and migmatites contain rare gabbro-diorite enclaves, in which Dantas et al. (2010) found a zircon population dated at ca. 3.53 Ga. These rocks have Sm-Nd T DM model ages up to 3.70 Ga, while the zircon Hf T DM ages vary between 3.70 and 3.90 Ga (Dantas et al. 2010(Dantas et al. , 2013. Thus, these data indicate that Eoarchaean components occur in this part of GB, which is similar to the Riacho de Santana region in the western Gavião Block.

Western Gavião block
The western part of the GB is composed of Palaeo-to-Neoarchaean rocks that are intruded by the Palaeoproterozoic Guanambi batolith and coeval rocks (e.g. Cordani et al. 1985;Rosa et al. 2000;Barbosa et al. 2012Barbosa et al. , 2013. The western GB, in the Riacho de Santana region, is divided into two tectonic units, which are gneiss-migmatite Archaean complexes that underwent Figure 3. Field photos. a -Outcrop of the Mairi orthogneiss. In this photo it is possible to observe the 3.64 Ga granodiorite gneiss paleosome and the 3.55 Ga granodiorite gneiss. b -Outcrop of the Riacho de Santana TTG in which the 3.35 Ga orthogneiss with mafic enclave occurs. c -Outcrop of the Sete Voltas TTG containing both the 3.42 Ga tonalite and the 3.14 Ga granitic leucosome. d -Outcrop photo of the 3.15-2.82 Ga leucodioritic gneiss from the Uauá Block. The small picture is a detail photo of the same rock. e and f -Sete Voltas TTG. In these photos is possible to notice the 3.42 Ga tonalite, the 3.14 Ga granitic leucosome and the biotite-rich reaction selvedges. a complex metamorphic evolution highlighted by granulite facies rocks (e.g. Rosa et al. 2000;Barbosa et al. 2013Barbosa et al. , 2020Medeiros et al. 2017). Rosa (1999) reported a U-Pb crystallization age of 3.35 Ga for a gneiss xenolith in the Palaeoproterozoic Cara Suja granite. An LA-ICP-MS zircon U-Pb age of ca. 3.35 Ga is considered as representative of the crystallization of the Riacho de Santana TTG (Barbosa et al. 2013(Barbosa et al. , 2020a (Figure 3(b)). It hasT DM ages between 3.91 and 3.59 Ga and ɛ Nd(t) varying from −7.0 to −0.1 (Barbosa et al. 2013(Barbosa et al. , 2020Teixeira et al. 2017).

Southern Gavião block
This part of the GB is bounded to the east by the southern portion of the Palaeoproterozoic Contendas-Jacobina Lineament (CJL) (Sabaté et al. 1990) and to the south by the Neoproterozoic Araçuaí Belt (e.g. Teixeira et al. 2017). Detailed geologic-geochronological studies in the GB have suggested a protracted evolution from the Palaeoarchaean to the Neoarchaean (e.g. Teixeira et al. 2017). The continental crust formed in the Palaeo-Mesoarchaean underwent metamorphism and partial recycling into granites and migmatites between 2.70 and 2.60 Ga (Santos-Pinto et al. 2012). The southern GB hosts TTG orthogneisses dated between 3.45 and 3.20 Ga (e.g. Nutman and Cordani 1993;Martin et al. 1997). Most of these granitoids intrude or encompass metavolcanicsedimentary sequences and greenstone belts that are scattered over the block (e.g. Nutman and Cordani 1993;Leal et al. 1996). Some examples of the Palaeoarchaean rocks are the Sete Voltas ( Figure 3(c, e, f)) and Boa Vista gneissic domes and associated felsic volcanics (Supplementary material and references therein).

Serrinha block (SB)
The SB is the smallest Mesoarchaean unit in the northern SFC (Teixeira et al. 2017) but is one of the best-known areas of the craton. It represents an approximately N-S elongated segment that is limited to the west and to the south by the Palaeoproterozoic Itabuna-Salvador-Curaçá Block (e.g. Sabaté 2002, 2004). The oldest rocks of the SB are Mesoarchaean (3.08-2.98 Ga) migmatites, TTGs, banded gneisses, mafic-ultramafic complexes, and mafic dikes of the Santa Luz Complex (Oliveira et al. 2010). According to Oliveira (2011), the banded gneiss unit represents the end product of the deformation of migmatites and mafic dikes during the accretion of the Palaeoproterozoic Rio Itapicuru Greenstone Belt onto the Archaean basement. Palaeoproterozoic intrusions related to the Itabuna-Salvador-Curaçá orogen Sabaté 2002, 2004) intrude the Archaean basement. Remnants of ~3.10 Ga migmatitic enclaves are found within the Ambrósio dome (Mello et al. 2006), and the Palaeoproterozoic Quijingue trondhjemite contains 3.31 and 3.62 Ga old, inherited zircons (Rios et al. 2008). This suggests that Palaeo-to-Mesoarchaean material formed the precursor crust of the Serrinha Block. From a geochronological and isotopic perspective, the Santa Luz Complex can be divided into two domains of grey gneisses (i.e. the Retirolândia -ca. 3.08 Ga and the Jacurici -ca. 2.98 Ga domains; Oliveira et al. 2010). Both of these domains are constituted of TTG suites, respectively, with Sm-Nd T DM model ages between 3.2 and 3.1 Ga and 3.20-2.90 Ga and the ɛNd(t) values varying between 0 and +1.1 and 0 and +4.9, respectively, suggesting a predominant juvenile origin (Table 1).

Uauá block (UB)
The UB is bordered to the west by the Archaean-Palaeoproterozoic Caldeirão Belt, to the east by the Palaeoproterozoic Rio Capim Greenstone Belt (Oliveira et al. , 2013 and to the south by the Serrinha Block. The oldest rocks in the UB are banded gneisses of 3.15-3.12 Ga (Oliveira et al. 2019) (Figure 3(d)), intruded by Mesoproterozoic layered anorthosite, peridotite, and diorite complexes, pre-metamorphic mafic dikes, and tonalite-granodiorite bodies. Neoarchaean nonmetamorphic norite-tholeiite dikes crosscut the country rocks in some places (Oliveira 2011;Oliveira et al. 2013 and references therein) (Supplementary material and references therein). With the exception of the Neoarchaean noritic (2.73 Ga) and tholeiitic (2.62 Ga) dikes (Oliveira et al. 2013), much of the basement rocks underwent granulite facies metamorphism and were later retrogressed to amphibolite facies. The felsic granulitic bodies, with interspersed garnet-bearing mafic granulites, are strongly foliated, frequently with horizontal or south-dipping low-angle foliation. The available isotopic data from the rocks of UB (Table 1) show ɛ Nd(t) between −6.6 and +1.6, indicating an origin associated with juvenile and crustal reworking processes. Cordani et al. (1999) obtained ages between 3.12 and 3.13 Ga for the Capim tonalite, whereas Oliveira et al. (2010) reported felsic igneous bodies with ages between 3.07 and 2.99 Ga. According to Oliveira (2011Oliveira ( , 2013, the younger tholeiitic dike swarm (2.62 Ga), which crosscuts the gneisses of the basement, may represent a failed arm of a Neoarchaean rift system.

Results and data evaluation
The geochronological and isotopic data that were compiled from the literature are summarized in Table 1 and allowed the observation of four different crustal differentiation events in the northern SFC with ages of 3.66-3.51 Ga; 3.45-3.30 Ga; 3.10-3.00 Ga; and 2.90-2.80 Ga. The Hf, Nd, and Sr isotopes data suggest that crustal reworking and juvenile processes contributed to the evolution of this part of the craton.

U-Pb zircon ages
The compiled zircon U-Pb ages presented in Table 1

Sr isotopes
According to Rollinson and Pease (2021), the Rb-Sr isotope system has the largest compatibility difference among parent and daughter elements, resulting in easy separation and fractionation of Rb and Sr between crust and mantle. This leads to a fast evolution of Sr isotopes in the continental crust relative to the mantle (with time, 87 Sr/ 86 Sr ratios in the crust will be greater than in the primitive mantle). However, one of the main drawbacks when applying this method is that both Rb and Sr are relatively mobile elements, which may affect the quality of the data when a sample has experienced interaction with fluids or thermal events (Rollinson and Pease 2021

Nd isotopes
The available 143 Nd/ 144 Nd (i), ɛNd (t) and T DM(Nd) data are very useful in the determination of the petrogenetic processes that contributed to the crustal evolution of the northern SFC because they can be utilized as indicators of the sources of the studied Archaean blocks (Zindler and Hart 1986). For the Gavião Block, the 143 Nd/ 144 Nd (i) varies between 0.5079 (e.g. migmatite/orthogneiss from the Riacho de Santana Complex, western GB - Barbosa et al. 2013) and 0.5093 (e.g. metakomatiite from the Umburanas greenstone belt, southern GB - Leal et al. 1998). The ɛ Nd(t) values range from −8.8 (e.g. gneiss from the Aracatu massif, southern GB - Santos Pinto, M.A 1996) and +11.6 (e.g. metakomatiite from the Umburanas greenstone belt, southern GB - Leal et al. 1998). The T DM(Nd) values vary between 2.84 Ga (e.g. tholeiitic volcanic from the Contendas-Mirante metavolcano-sedimentary sequence, southern GB -Marinho 1991) and 4.22 Ga (e.g. gneiss from the Aracatu Massif, southern GB - Santos Pinto, M.A 1996).

Hf isotopes
The compiled 176 Hf/ 177 Hf (i) , ɛ Hf(t) , and T DM(Hf) data are a very useful tool in the determination of the petrogenetic processes that contributed to the crustal evolution of the northern SFC because as the Nd isotopes, they can be utilized as indicators of the sources of the studied Archaean blocks.
For the Gavião Block, the 176 Hf/ 177 Hf (i) ratio varies between 0.2802 (e.g. TTG from the Piritiba region, northern Gavião Block - Oliveira et al. 2020) Oliveira et al. 2019). According to the same authors, the ɛ Hf(t) vary between −8.53, obtained for the leucodioritic gneiss, and +3.56, for the mafic granulite, and the T DM(Hf) data of the UB varies between 3.43 and 3.08 Ga. Up-to-present-day, there are no available Hf isotope data from the Serrinha Block. The Hf isotope data are shown in supplementary material 2.2

Zircon U-Pb age and isotopic constraints
Geochronological data compiled in this article suggest the occurrence of four episodes of crust formation in the northern São Francisco Craton (e.g. 3.66-3.51 Ga, 3.45-3.30 Ga, 3.20-3.00 Ga, and 2.90-2.77 Ga). The ca. 3.42 Ga TTG's (e.g. Sete Voltas TTG) produced by partial melting of Archaean mantle sources, with hornblende garnet residue, represent the more pervasive magmatic precursors to the São Francisco Craton (e.g. Martin et al. 1997;Guitreau et al. 2012;Teixeira et al. 2017). The 3.33 to 3.29 high-silica rhyolitic-granitic systems have formed after a period of crustal growth and stabilization of a thick continental lithosphere and are related to intraplate magmatism and intracrustal differentiation processes (e.g. Zincone et al. 2016). The igneous protoliths of the 3.17-3.15 Ga migmatite-gneiss and porphyritic granodiorites were produced by new partial melting of an already differentiated crust at depths of ~30-45 km (e.g. Martin et al. 1997). Lastly, ~2.60 Ga high-K granites (e.g. Caraguataí syenitic suite - Cruz et al. 2012; also referred as Caraguataí granitic suite by Lopes et al. 2021), Fe-Ti-V-rich mafic dikes (e.g. Rio Jacaré Sill -Brito 2000) and alkaline granitic intrusions (e.g. Pé de Serra granite -Marinho 1991) related to the late-stage collisional event were emplaced along the ca. 3.40 and ca. 3.15 Ga highgrade migmatite-gneiss terranes (e.g. Martin et al. 1997). According to Lopes et al. (2021), the occurrence of the ca. 2.70 Ga high-K granites of the Caraguataí suite suggests that the southern part of the GB was already stabilized at this period. Likewise, 3.64 Ga Palaeoarchaean gneisses have negative ɛ Hf(t) values and T DM(Hf) ages between 3.75 and 4.15 Ga, indicating late Hadean to Eoarchaean sources or contamination by older Eoarchaean continental crust. The 3.10-3.00 Ga rocks of the Serrinha Block have slightly positive ɛ Nd(t) values and T DM ages between 3.10 and 3.20 Ga, suggesting that their sources may have been of juvenile origin while in the Uauá Block shows slightly positive and negative ɛ Nd(t) values and T DM ages between 3.20 and 3.30 Ga, indicating Palaeoarchaean sources and some amounts of juvenile contribution during its evolution, which is different to what occurs in the GB. The 2.90-2.77 Ga period is characterized by widespread anatexis, and the 2.70-2.60 Ga period is related to the occurrence of granitic magmatism in the southern GB (e.g. Barbosa et al. 2012).

Nd and Sr isotopic data
The Nd T DM ages and negative to positive εNd (t) for the SFC blocks confirm a complex Archaean history with multiple crustal reworking stages associated with mantle sources (Figure 4(a-f)) (e.g. Martin et al. 1997;Guitreau et al. 2012;Zincone et al. 2016;Teixeira et al. 2017). The Northern and Southern Gavião blocks share ca. 3.50 and 3.30 Ga juvenile sources with pervasive crustal partial melting at 3.42-3.45 and 3.20-3.30 Ga (Figure 4(a,b)). Specifically, the Sete Voltas complex records complementary Nd isotopic patterns, indicating that the ca. 3.15-3.17 Ga granodioritic to granitic rocks were generated by partial melting of the ca. 3.42 Ga TTGs (Figure 4(c)). A ca. 3.00 Ga accretionary process with juvenile and reworked sources is recorded in the Brumado Complex and in the Contendas-Mirante metavolcanicsedimentary sequence in the Southern Gavião Block (Figure 4(a,c)). The Western Gavião Block presents a ca. 3.30 Ga crustal accretion event with mixed 3.30 Ga juvenile and ca. 3.50-3.60 Ga crustal sources and younger ca. 3.00 Ga partial melting of the previous ca. 3.10 Ga continental crust (Figure 4(d)). Likewise, the Uauá Block displays 3.10 Ga and 2.90 Ga juvenile rocks with 3.00 and 2.80 Ga crustal reworking (Figure 4(e)). Lastly, the Serrinha Block presents positive εNd(t) values with similar evolution to Uauá indicating some contribution from 3.10 to 3.00 Ga components of mantle-derived and minor 3.00 Ga crustal reworking sources (Figure 4(f)).
The lower initial 87 Sr/ 86 Sr and Rb/Sr ratios, relative to the 3.30 Ga high-Si plutonic-volcanic system, of both the 3.50-3.40 Ga TTGs and the 3.20 to 3.00 Ga granodioritic to granitic rocks (Figure 5(a,b)) could indicate that these rocks are generated by anatexis of the lower continental crust (e.g. White and Powell 2010). In contrast, high initial 87 Sr/ 86 Sr and Rb/Sr ratios associated with the high-Si granitic magmatism (Figure 5(a,b)) could have originated by partial melting of high K/Na rocks in the upper continental crust (e.g. Zincone et al. 2016). In addition, Rb/Sr ratios vs. U-Pb zircon diagram (Figure 5(a)) suggest a linear enrichment evolution for the ca. 3.40 Ga TTGs, high initial Rb/Sr ratios for the ca. 3.30 Ga high-Si granitic magmatism and lower ratios for the ca. 3.00 Ga tholeiitic rocks.
The Sete Voltas complex is the best example to understand the Palaeoarchaean crustal evolution of the São Francisco Craton. The ca. 3.42 Ga TTG rocks have low initial 87 Sr/ 86 Sr and Rb/Sr ratios, whereas 3.15 to 3.17 Ga granitic to granodioritic rocks have higher initial 87 Sr/ 86 Sr and Rb/Sr ratios (Figure 6(a,b)). Moreover, T DM(Nd) ages and ε Nd(t) values show progressive evolution and fractionation from the 3.42 Ga TTGs towards the 3.17-3.15 Ga granites and . ε Nd(t) vs age diagrams for the Archaean blocks of the northern São Francisco Craton. A -Southern Gavião Block, indicating the occurrence of juvenile and crustal reworking processes. B -Northern Gavião Block, suggesting the occurrence of juvenile and crustal reworking processes in two different periods. C -ε Nd(t) vs age diagram for the 3.42 Ga Sete Voltas TTG, the 3.30 Ga Contendas rhyolite, the 3.17-3.14 Ga Sete Voltas granites, the 3.0 Ga tholeiitic rocks from the Contendas-Mirante metavolcanic-sedimentary sequence, suggesting the occurrence of crustal reworking and juvenile processes. D -Western Gavião Block, indicating the occurrence of different periods of crustal reworking and juvenile processes. E -Uauá Block, suggesting two different periods of juvenile and crustal reworking processes. F -Serrinha Block, indicating essentially juvenile processes for the origin of this crustal segment. granodiorites (Figure 6(c)). Therefore, combined whole-rock Nd and Sr isotopic patterns indicate that the ca. 3.17 Ga Sete Voltas granodiorite and the 3.14 Ga granite are derived from the 3.42 Ga Palaeoarchaean TTGs (e.g. Martin et al. 1997) (Figure 6(d)).

Hf isotopic data
The compiled Hf isotopes data do not allow the division of the GB in Northern, Southern, and Western Gavião blocks in the Archaean; thus, it is merely geographical (Figure 7(a,b)). The integrated Hf isotopic dataset suggests that an ancient crust with T DM(Hf) between 3.75 and 4.15 Ga reworked at 3.64-3.55 Ga for the Mairi orthogneiss, in the northern portion of the SFC, which is evidenced by the ε Hf(t) values between −9.3 and −0.3 (Figure 7(a,b)) (supplementary material 2) (e.g. Oliveira et al. 2020). New crust generation, with T DM(Hf) between 3.50 and 3.90 Ga, and reworking at 3.40 and 3.30 Ga, associated with minor juvenile contributions is represented by the 3.42 Ga Sete Voltas TTG (e.g. Martin et al. 1997;Guitreau et al. 2012) and the 3.30 Ga Mundo Novo and Contendas rhyolites (Figure 6(a,b)) (e.g. Zincone et al. 2016).
The older ca. 3.64 Ga TTG series from the northern São Francisco Craton have negative ε Hf(t) values and are less geochemically enriched, indicating reworked sources (e.g. Figure 5. Sr isotopic data for the Archaean São Francisco blocks. a -Rb/Sr vs age diagram for the northern SFC, suggesting high initial Rb/Sr ratios for the 3.30 Ga rhyolitic-granitic systems, a linear enrichment evolution for the 3.45 Ga TTGs and low initial Rb/Sr ratios for the 3.1-3.0 Ga tholeiitic rocks. b -87 Sr/ 86 Sr(i) vs age diagram for the rocks of the northern SFC. The lower 87 Sr/ 86 Sr(i) for the 3.5-3.4 Ga tonalite residue and 3.2-3.0 Ga granodioritic to granitic leucosome may indicate anatexis of the lower crust, while high 87 Sr/ 86 Sr(i) in high-Si granitic magmatism suggest partial melting of high K/Na rocks in the upper continental crust. Oliveira et al. 2020). In contrast, the 3.50 to 3.20 Ga TTG (e.g. Guitreau et al. 2012;Zincone et al. 2016) and granodioritic magmatism present negative and positive ε Hf(t) values, enriched trace element compositions, and inherited zircon grains and cores (e.g. Oliveira et al. 2020). The 3.66 and ca. 3.45-3.15 Ga SFC terranes experienced several partial melting events with multiple magmatic pulses, which have obliterated the original protolith signatures. Furthermore, it also reflects a variable mixing of TTG crust and juvenile sources during the Palaeoarchaean (Figure 8). Specifically, the Hf isotopic data support a predominantly reworked crustal source to the 3.64 Ga Mairi orthogneiss; evolved crust and limited juvenile contribution to the 3.45 Ga TTGs; felsic protolith to ~3.30 Ga high-silica magmatism and significant assimilation of Eoarchaean/Palaeoarchaean precursors for the 3.17-3.15 Ga migmatite-gneiss and granodiorites (e.g. Zincone et al. 2016;Oliveira et al. 2020). This scenario is similar to the Hf evolution documented in the Kaapvaal, Pilbara, and Zimbabwe cratons (e.g. Kemp et al. 2015;Petersson et al. 2019;Gardiner et al. 2021;Hofmann et al. 2022). Lastly, different structures, ages, and geochemical profiles support that the 3.60 to 3.10 Ga Palaeo-to Mesoarchaean terrane recorded in São Francisco craton were formed from heterogeneous sources with distinct crustal anatexis paths.

Crustal differentiation evolution and Archaean correlations
The comparison among Archaean cratons requires understanding that they have evolved by multiple ways of crustal differentiation and recycling (e.g. Moyen et al. 2021). Kaapvaal, Singhbhum, and Pilbara cratons are classic Palaeoarchaean cratons, which stabilized much earlier than most other cratons (e.g. Chaudhuri 2020;Hofmann et al. 2022). The orthogneiss terrains have zircon ages of ca. 3. 66-3.63, 3.52-3.51, and ca. 3.30 Ga that also support the existence of Eo-to Palaeoarchaean crust in the São Francisco and Zimbabwe cratons (e.g. Hofmann et al. 2022;Santos et al. 2022). Specifically, the SFC presents multiple continental crust growth peaks at 3.30 and 3.00 Ga combined with moderate peaks at ca. 3. 66-3.55, 3.45-3.42, and 3.17-3.15 Ga. It is similar to Pilbara (Western Australia) and Kaapvaal-Zimbabwe cratons (southern Figure 6 Nd and Sr isotopic data for the Sete Voltas complex. A -87 Sr/ 86 Sr(i) vs age diagram indicating that the 3.42 Ga TTG residue has lower 87 Sr/ 86 Sr(i) than the 3.17 Ga Sete Voltas granodiorite and the 3.14 Ga Sete Voltas granitic leucosome. B -Rb/Sr vs age diagram showing that the 3.42 Ga TTG has lower Rb/Sr ratio than the 3.17 Ga Sete Voltas granodiorite and the 3.14 Ga Sete Voltas granitic leucosome. C -ε Nd(t) vs age diagram indicating that the 3.42 Ga TTG could have been the source of the 3.17 Ga Sete Voltas granodiorite and the 3.14 Ga Sete Voltas granitic leucosome. D -143 Nd/ 144 Nd vs 87 Sr/ 86 Sr diagram suggesting that the 3.17 Ga Sete Voltas granodiorite and 3.14 Ga granitic leucosome are derived from the 3.42 Ga Sete Voltas TTG.
The systematic U-Pb zircon ages in the São Francisco and other cratons indicate that 3.66-3.55 Ga and 3.45 Ga constituted a period of significant Eo-to-Palaeoarchaean crustal growth marked by TTG magmatism, while the T DM(Hf) values obtained suggest the occurrence of reworking of Hadean to Eoarchaean crust (Figure 9(a,b)) (e.g. Martin et al. 1997;Horstwood et al. 1999;Guitreau et al. 2012;Petersson et al. 2020;Santos et al. 2022). The older crustal differentiation is represented by the 3.65-3.55 Ga Mairi TTG complex derived from high-Sr protoliths in the northern GB (Figures 5(a,b), 6(a)). In contrast, in the southern GB, the 3.45-3.42 and 3.35 Ga Sete Voltas complex represented the partial melting of Eoarchaean crust with minor juvenile contribution (e.g. Martin et al. 1997). Indeed, the 3.55 to 3.42 Ga rocks were the main sources for Mesoarchaean rocks generated by partial melting (e.g. Horstwood et al. 1999;Kemp et al. 2015;Chaudhuri 2020;Gardiner et al. 2021). The 3.33 to 3.29 Ga high-Si volcanism would represent the continental rifting for the SFC (e.g. Zincone et al. 2016), while 3.53 to 3.17 Ga volcanicsedimentary successions and autochthonous groups followed by 3.20 to 3.10 Ga continental break-up are recorded in the Pilbara Craton (e.g. Smithies et al. 2007).

Figure 7.
Archaean Hf isotopic data for the northern São Francisco Craton. A -ε Hf(t) vs age diagram suggesting that the sources of the 3.64 Mairi orthogneiss, in the northern portion of the GB, is associated to reworking of Hadean crust, while the sources of the 3.42 Ga Sete Voltas TTG; 3.30 Ga Contendas and Mundo Novo rhyolites and 3.15 Ga leucodioritic gneiss of the Uauá Block are related to crustal reworking of Palaeo-to Mesoarchaean crustal sources. The diagram also suggests that the origin of the 3.15-2.80 Ga mafic granulites of the Uauá Block is associated with a Palaeo-to Mesoarchaean mantle source. B -Detail ε Hf(t) vs age diagram showing the evolution of the Gavião Block.
The northern and southern portions of the Gavião Block recorded similar geological evolution since ca. 3.30 Ga, which is evidenced by high-Si magmatism with mixed reworked and juvenile sources (Figure 8(a-d)). The 3.20, 3.10, and 3.00 Ga pervasive crustal recycling events are also documented in all of the northern SFC blocks.
Moreover, the isotopic and chemistry data support that the 3.10 to 3.20 Ga granites and porphyritic granodiorites, from Kaapvaal, Pilbara, and São Francisco cratons were derived from the Palaeoarchaean crustal sources compatible with the 3.40-3.50 Ga TTG rocks (e.g. Martin et al. 1997  Material 1). A -Sr vs age diagram indicating that the oldest rocks of the northern SFC have higher Sr contents. B -87 Sr/ 86 Sr(i) vs age diagram showing two groups of rocks, which indicate that crustal reworking and juvenile processes occurred in the northern SFC. Cε Nd(t) vs age diagram showing the crustal evolution processes that occurred in the northern SFC-D -ε Nd(t) vs 87 Sr/ 86 Sr(i) diagram indicating that the crustal evolution of the northern SFC is related to juvenile and crustal reworking processes. Figure 9. Hf isotope data. A -εHf (t) vs age diagram showing that the crustal evolution of the northern São Francisco craton had similarities with that of Kaapvaal, Pilbara and Zimbabwe cratons. This suggests that similar processes occurred in different portions of the early Archaean crust. The data from Kaapvaal and Pilbara cratons were compiled from Gardiner et al. (2021) and the data from Zimbabwe craton were compiled from Hofmann et al. (2022). Crust values of 0.0113 and 0.005 from Bouvier et al. (2008). DM trend from Vervoort and Blichert-Toft (1999) and Vervoort et al. (2017). B -Histogram indicating the distribution of the T DM(Hf) data of the northern São Francisco Craton. 2020; Mühlberg et al. 2021). Moreover, the combined positive and negative ε Hf(t) and ε Nd(t) values support mantle and crustal sources during 3.15-3.00 Ga northern SFC and Pilbara craton crustal evolution (e.g. Martin et al. 1997;Smithies et al. 2007). Lastly, the 2.95 to 2.77 Ga high-K granitic magmatism occurs in a thicker and stabilized continental crust (e.g. Lana et al. 2013). Overall, emplacement of younger (<2.9 Ga) high-K granitic and sanukitoid magmas, followed by crustal stabilization, is a pervasive phenomenon in Archaean terrains (e.g. Moyen and Martin 2012;Laurent et al. 2020;Ferreira et al. 2021).
Compiled geochronological and Nd-Sr-Hf isotope data suggest that the northern part of the SFC developed into stable crustal blocks since ca. 3.15 Ga (Figures 8, 9(a)). Moreover, these data reveal that the Archaean high-and low-grade metamorphic terranes of the northern SFC were formed from distinct parental magmas and have complex and different early to mid-Archaean histories (Figure 8(a-d); Gavião, Serrinha, and Uauá blocks) (e.g. Martin et al. 1997;Guitreau et al. 2012;Teixeira et al. 2017;Oliveira et al. 2020;Moreira et al. 2022;Santos et al. 2022). Therefore, isotope and geochemical data support multiple recycling processes, including pervasive crustal differentiation of mantle-derived melts during the formation of the proto-São Francisco Craton. However, complementary studies are necessary to better understand the Eo-to Palaeoarchaean crustal differentiation and juvenile magma addition in the SFC.

Conclusion
The continental growth of the SFC occurred by the combination of diverse crustal components via sporadic contribution of juvenile sources and prolonged reworking of the Haden to Palaeoarchaean crust associated with multiple deformations and partial melting events during the 3.65 to 2.80 Ga period. Thus, based on the compiled data, it is possible to conclude that: • The Nd isotope data suggest that the Eo-to-Mesoarchaean crustal evolution of the northern SFC was associated with juvenile and crustal reworking processes. • The lower 87 Sr/ 86 Sr(i) for the 3.50-3.40 Ga tonalite and 3.20-3.00 Ga granodiorites to granites suggest anatexis of the lower crust, while high 87 Sr/ 86 Sr(i), for the 3.30 Ga, high-Si granitic magmatism suggests partial melting of high K/Na rocks in the upper continental crust.
• The Hf isotope data suggest the occurrence of ca. 4.15-3.90 Ga crustal sources to the Mairi orthogneiss (northern Gavião Block) and a second large period of crust generation between 3.75 and 3.50 Ga, with a restricted contribution of juvenile sources. At 3.30 Ga and, mainly, at 3.00 Ga, an intense mixing of older crusts with juvenile magmas occurs. • The northern part of the SFC shows similar crustal evolution with Kaapvaal and Zimbabwe Cratons, in southern Africa and with Pilbara Craton, in western Australia, at least until 3.00 Ga, suggesting that, in the Archaean, the same processes occurred in different parts of Earth's primitive crust. • Despite these conclusions, some questions about the early evolution of the northern São Francisco Craton remain unanswered. For instance,: i) what is the nature of the source(s) of the 3.65-3.42 Ga TTG gneisses? ii) which early-Earth processes did give rise to the parental magmas of the gneisses' protoliths ?