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The recognition and evaluation of polycyclic processes in sedimentary units are critical for proper provenance analysis and sedimentary system interpretation. The chemical composition and textural maturity of detrital tourmalines and zircons allow identification of sediment source areas, transport, and deposition. This study investigates the origin and history of post-Gondwanan sediments of the Tupanciretã Formation in southern Brazil, which lacks provenance studies. The Tupanciretã Formation is in a similar setting of the Bauru Supersequence at the uppermost portion of the Paraná Basin. Detrital zircon ages indicate sediment provenance from the Transamazonian, Grenvillian, and Brasiliano orogenic cycles of the Rio Grande do Sul Shield and younger grains (280-128 Ma) record contribution from the Choiyoi and Serra Geral igneous events, with a maximum deposition age of 127 Ma. Detrital tourmaline chemical analyses points to the Sul-riograndense Shield as the ultimate source, with metapelitic, metapsamitic and granitic origins. The predominant degrees of roundness are well rounded to rounded suggest evidence of sediment recycling from sedimentary units of the Paraná Basin, with important aeolian reworking involved. Zircon U–Pb signatures are compatible with the eastern sector of the Botucatu Formation in Rio Grande do Sul as the immediate source and the northeastern Sul-riograndense Shield as the ultimate source. Intermediate sources between the Sul-riograndense Shield and the Tupanciretã Formation were Gondwanan sedimentary units of the Paraná Basin, with possible participation from the Camaquã Basin. • The grains indicate important recycling of sediments with multiple sources, With important analysis of detrital zircons. • Detrital tourmalines indicate the participation of multiple basement rocks as the ultimate source. • There was an ancient drainage percolating from SSE to NNW, carrying polycyclic sedimentary rock material. • The high degrees of grain roundness indicate polycyclic sedimentary events, with a maximum deposition age of 127 Ma. [ABSTRACT FROM AUTHOR]

The Guanchín Formation is a sedimentary unit that was deposited during the Andean orogeny and is preserved in the Fiambalá Basin in NW Argentina. It records an advanced stage of the broken-foreland evolution in a transitional zone between the morphotectonic domains of the Precordillera, the Sistema de Famatina, the Western Sierras Pampeanas, and the southern Puna. Furthermore, it preserves a record of Late Miocene explosive volcanism that is common in all the foreland basins in this Andean segment. The Guanchín Formation was studied at Cuesta Loro Huasi and Guanchíncito sections, where seven facies associations (FA) were recognized. These represent ephemeral sandy braided fluvial systems with thin mud floodplains (FA1), sheetflow-dominated sandy-tuffaceous alluvial plain (FA2), perennial sandy braided fluvial system (FA3), fine-grained alluvial plain built up by unconfined flows and less terminal splays (FA4), sheetflow-dominated sandy alluvial plain (FA5), and sandy-gravelly (FA6) and sandy-dominated (FA7) braided fluvial system, arranged in chronological order from oldest to youngest. To date the formation, zircon U/Pb ages from tephras were obtained from the Cuesta Loro Huasi section, which yielded depositional ages of 6.10 ± 0.07, 5.89 ± 0.09, 5.60 ± 0.06, and 5.20 ± 0.05 Ma, while a fifth sample from the Guanchíncito section yielded an age of 3.26 ± 0.05 Ma. Additionally, detrital zircon analyses were performed to infer sediment provenance and constrain the maximum depositional age of sedimentary units. These data combined with paleoenvironmental analysis and clast compositions in conglomerates suggest that the Western Sierras Pampeanas had been uplifted around ∼6 Ma. By this time the drainage was dissipated as a distributary fluvial system (DFS) under semiarid climatic conditions, which received sediments from northern, eastern, and to a lesser extent from western sources. Around ∼3 Ma the basin started to receive coarse-grained sediments of braided fluvial systems (FA6 and 7) indicating a closer proximity to the Pampean sources areas. The Guanchín Formation records an overall progradational trend manifested through two minor progradational cycles, each one controlled by changes in the equilibrium profile and accommodation space of the basin. This trend is likely associated with a basinward increase in the subsidence rate or enhanced water availability in the headwaters, potentially linked to tectonic uplift in the eastern and/or northern ranges, including the final uplift of the southern Puna. Since previous works placed the deposition of the overlying Rodado de la Puna Formation deposition began at 4 Ma, these news ages suggest the top of the Guanchin Formation is younger than previously thought. • Guanchín Formation deposition began around 6.24 ± 0.38 Ma, extending to 2.69 ± 0.38 Ma. • It was deposited as a distributary fluvial system with multiple progradational pulses. • Sediment source was mainly from North and East, where Sierras Pampeanas outcrops. • Pampean sources prevail in Guanchín Formation's upper member. • Sierras Pampeanas uplift fully partitioned the Fiambalá Basin. [ABSTRACT FROM AUTHOR]

The Neogene Barreiras Formation is composed of continental to shallow marine sedimentary rocks that fringe the Brazilian Atlantic coast. Due to the large outcropping extent, various open questions about the evolution of this unit are still under debate. We present new U–Pb detrital zircon age spectra of four samples from the southern Espírito Santo state (Marataízes section) and two samples from the southern Bahia state (Arraial section). In both of the studied outcrops, a basal succession composed of coarse-grained cross-bedded sandstone, conglomerate and arkose with mudstone and claystone intercalations is superposed by an upper succession composed of massive sandstone, conglomerate and wacke. The U–Pb detrital zircon age spectra of all samples are dominated by Cambrian and Neoproterozoic grains. However, while the lower portion of both sections is dominated by Ediacaran-Cambrian grains, their upper portions also present significant Cryogenian-Tonian and sparse Paleoproterozoic (mainly Rhyacian and Statherian) and Neoarchean grains. This marks an important provenance shift within the Barreiras Formation, with a simple, local provenance sourced from the G1 to G5 granite supersuites of the Brasiliano Araçuaí Orogen for the basal layers contrasting with exposure of older basement rocks and Neoproterozoic anorogenic suites during deposition of the superior layers. We interpret the lower coarse sandstone and arkose-rich succession as deposited in an alluvial setting, with mud/claystones related to local flooding plains. Tectonic movements related to the evolution of the Atlantic passive margin, as described in previous works, caused a renewed uplift of the basement areas, exposing and denuding older rocks. Then, the upper layers deposited through debris flows covering the first succession. Further geochronological data is needed to test if the erosional event responsible for exposure of older basement rocks and sourcing of the upper layers would correspond to the Tortonian Sea level fall, related to growth of the Antarctic ice sheet to its present size. In this case, deposition of the lower succession would have occurred during the early Miocene, and the upper succession during the Pliocene. Our results shed light in the complex evolution of the sedimentary rocks generally grouped under the Barreiras Formation, and suggest important tectonic and climatic shifts during the Neogene evolution of the Brazilian Atlantic coast. • Detrital zircon U–Pb analysis of two sections of the Barreiras Formation • Source areas dominated by late Neoprotezoic to Cambrian sources (G1-G5 plutons) • Archean-Paleoproterozoic basement exposed in the source areas upsection • Tectonic, climatic and sea-level changes were possible provenance shift drivers • Complex evolution of the sedimentary rocks of the Barreiras Formation [ABSTRACT FROM AUTHOR]

The eastern and southern Precambrian basement of Mexico is composed of crustal blocks linked to northern Amazonia before and during the assembly of the Rodinia supercontinent. In this paper, we examine an extensive basement block known as the Sierra de Juárez Complex (SJC) in southern Mexico by integrating fieldwork, in-situ zircon U–Pb geochronology by LA-ICPMS and whole-rock geochemistry by X-ray fluorescence. The results provide evidence for a continuous low-to high-grade metamorphic succession here re-defined as the Pochotepec suite (PS), which comprises an upper lithodeme with volcanosedimentary precursors and a lower lithodeme that includes mafic to intermediate orthogneisses and migmatites. The analytical results suggest that the PS protoliths originated in a continental-arc tectonic setting ca. 1080-1050 Ma along the northern edge of Amazonia before the consolidation of Rodinia. In addition, xenocrystic zircon U–Pb analyses indicate the presence of a recycled older crust of ca. 1200–1300 Ma. Finally, U–Pb data of recrystallized zircon rims and younger metamorphic zircon grains recorded the timing of metamorphism and anatexis of the PS during the early Tonian (954-933 Ma). The crystallization ages of two trondhjemitic leucosomes of 954 and 933 Ma strongly support the migmatization age. The Tonian metamorphic/anatectic episode of the PS differs in grade and age from the typical metamorphism related to the amalgamation of Rodinia reported in Mexico and Colombia (granulite-facies at ca. 990 Ma). Therefore, we interpret this event as produced by either post-orogenic crustal collapse or contractive tectonics. • The Pochotepec suite (PS) in southern Mexico belongs to the Sierra de Juárez Complex and consists of a Stenian – Tonian metamorphic sequence. • The Pochotepec suite originated during continental-arc magmatism along the leading edge of Amazonia during the late Stenian. • The Pochotepec suite underwent Tonian lower-to-medium-grade metamorphism and anatexis after the Rodinia assembly. • The Pochotepec suite followed a different tectonic evolution relative to the Oaxaquia-Putumayo block after the Rodinia assembly. • The Pochotepec suite correlates with the Chiapas Massif Complex in southeastern Mexico. [ABSTRACT FROM AUTHOR]

In the central region of the Precordillera, San Juan Province, Silurian silicoclastic sedimentites of the Los Espejos Formation crop out in the Jáchal River area. To the south of this region, an equivalent unit is recognized in the San Juan River area (Tambolar Formation). Both units present similar lithological characteristics, however, it has not yet been defined if they share source areas of detrital contributions. On the other hand, for the Jáchal River sector, it is proposed to establish if there were changes in the regions from where the sub-basin received sediment contributions during the Devonian, which can be seen reflected in the detrital zircon contribution patterns of the overlying unit (Talacasto Formation). The present work is part of a series of studies tending to determine the nature and provenance of the Silurian-Devonian sequences of the Central Precordillera. On this occasion, detrital zircon patterns of the detrital sources of the Los Espejos Formation are analyzed and compared with the information obtained for the Silurian Tambolar Formation (San Juan River area) and the overlying Devonian Talacasto and Punta Negra formations (Jáchal and San Juan rivers areas). To characterize and compare the studied units, different methodologies were applied, namely sedimentary petrography, heavy minerals studies, and morphological and isotopic analyses of detrital zircons. The analysis of thin sections allowed determining textural and compositional parameters. Through the predominance of detrital minerals, it was possible to establish that the studied units are composed of quartzite-type rocks coming from mature areas, with low percentages of lithic components and abundant opaque heavy minerals of the hematite group. The study of heavy minerals, especially morphological and typological parameters of detrital zircons, allowed to establish recycled and plutonic sources as main modes, as well as the changes that occurred during the basin filling dynamics for Silurian and Devonian times. On the other hand, U–Pb isotopic analysis in detrital zircons indicate that the Pampean-Brasiliano orogenic cycle composes the main source of detritus with ages between 511 and 816 Ma. In second place are the Mesoproterozoic ages, represented by the interval from 1000 to 1350 Ma. The youngest detrital ages show a maximum sedimentation age of 478.5 ± 4.4 Ma (Tremadocian), indicating that younger sources of contribution correspond to the Famatinian Orogen. The Kolmogorov-Smirnoff test revealed that the studied Silurian-Devonian units studied have similar patterns of sedimentary contributions, which suggests that the sources of provenance were common in both regions and remained active throughout the entire time interval, without significant changes. • The Los Espejos Fm evidences multiple cycles of erosion-transport-sedimentation. • The Pampean-Brasiliano orogen represents the main source of sediments. • The provenance proxies indicate a connection between the Jáchal and San Juan Rivers depocenters. • The main sources of sediments are the Western and Eastern Pampean Ranges. [ABSTRACT FROM AUTHOR]

The genesis of Precambrian granitic batholiths related to supercontinent assembly is controversial, especially regarding their generating processes and tectonic settings. The present study focused on the Pelotas Batholith (Magmatic-arc domain) of the Dom Feliciano Belt, which comprises the southern segment of the Mantiqueira Province in southeastern South America. New U–Pb and Lu–Hf zircon data from plutonic rocks with evidence of magma mixing and mingling, as well as assimilation of wall rocks, suggest multi-stage magmatism related to flare-up episodes of intense magmatism, potentially triggered by changes in the tectonic setting. U–Pb zircon analyses yielded crystallization ages of granodioritic gneiss xenolith at 691.5 ± 7 Ma, microgranodiorite xenolith at 645.9 ± 3.7 Ma, host monzogranite at 634.4 ± 4.4 Ma, and intrusive syenogranite at 620.1 ± 4.7 Ma, all intruded by syenogranitic pegmatite at 606.9 ± 1.7 Ma. Other analyses were performed on calc-alkaline granite (633 ± 4 Ma) and peraluminous granite (609.6 ± 2.2 Ma). The Lu–Hf data highlights a model age interval ranging from 1.7 to 1.3 Ga with εNd values between −4 and 1, except for the pegmatite sample which also includes Paleoproterozoic and Archean model ages (3.3-1.6 Ga) and εNd values between −33 and −1. Furthermore, the acquired data, together with the gathered dataset Dom Feliciano Belt granites, emphasizes a contribution from slightly juvenile to crustal sources, with model ages ranging primarily from Statherian-Orosirian to Mesoproterozoic. Signature patterns are consistent with sources from African basement rocks. • The studied magma mixing outcrop represents the Granite belt's fractal evolution. • The magmatic suites are primarily classified as I-Type and S-Type granites. • The Hf isotopes present mainly Meso-to Paleoproterozoic model ages (1.7-1.3 Ga). • The εHf values are primarily slightly negative to positive. • The U–Pb dataset shows well-defined intervals of magmatic pulses. [ABSTRACT FROM AUTHOR]

The precursor basin of the Araçuaí – West Congo Orogenic System (AWCO) formed a large gulf within the São Francisco – Congo Paleocontinent (SFCP), where the diamictite-bearing Macaúbas Group was deposited during the Neoproterozoic. However, the lack of robust age constraints on the Cryogenian glaciogenic successions prevents correlation to one or both of the Cryogenian Snowball Earth glaciations. The present study introduces new field data and new U–Pb detrital zircon data from diamictite-bearing units on the southern margin of the São Francisco Craton, in the northeastern Araçuaí Orogen. This region is much closer to possible Ediacaran-Cryogenian igneous rocks of the southern São Francisco craton than other regions previously studied for the Macaúbas Group, enhancing the probability of detecting detrital minerals from those rocks, if they were involved as source areas. In the studied region, the Macaúbas Group is composed of metadiamictite with sparse clasts and schistified metagraywacke with bulk mineralogy similar to the quartz-muscovite-feldspar matrix of the metadiamictites. U–Pb (LA-MC-ICP-MS) dating of 182 detrital zircon grains from the Lower Chapada Acauã Formation forming the syn-glacial sequence yielded main age peaks at 939 ± 3 Ma, 1409 ± 10 Ma, 1822 ± 8 Ma, 2044 ± 7 Ma, 2551 ± 9 Ma and 3103 ± 19 Ma. The youngest concordant zircon grain found in this study aged 753 ± 12 Ma. U–Pb (LA-MC-ICP-MS) dating of 104 zircon crystals from a granitic clast recovered from the diamictite exhibits highly discordant data plotting in distinct Discordia lines with upper intercept ages of 2.0 Ga, 2.5 Ga, 2.6 Ga and 3.2 Ga, indicating derivation from the adjacent cratonic basement. The U–Pb age spectra suggests important contribution from the Archean and Paleoproterozoic basement of the São Francisco – Congo paleocontinent and metamorphic complexes, from the Mesoproterozoic intrusive and volcanic rocks of São Francisco Craton, and from the Tonian Salto da Divisa Suite. Despite the relative abundance of Cryogenian zircon grains in the surrounding prospective source areas, the studied rocks lack this interval age. The glaciogenic events in the Macaúbas basin system probably did not sample rocks with these age intervals due to the general characteristics of this type of deposit or because the sources were not exposed. Thus, the lower diamictite-bearing units of the Macaúbas Group in the northeastern São Francisco craton were deposited after ca. 753 Ma, but their correlation to either the Sturtian or Marinoan global glaciations remain speculative. • U–Pb detrital zircon data of Chapada Acauã Formation reveals a younger sedimentation age. • Top diamictite bearing unit of Macaúbas Group with Upper Tonian detrital contribution. • Data corroborates coevality of Upper Macaúbas basin system and Jequitinhonha Complex. [ABSTRACT FROM AUTHOR]

Sedimentary basins with epiclastic and volcanoclastic components are important geotectonic components for understanding the complex evolution of orogenic systems. The age, provenance and tectonic setting of ancient basins are, however, often hard to constrain, especially in the high-grade core of ancient mountain belts where original sedimentary and stratigraphic relations have been largely obliterated by deformation and metamorphism. In this case, analytical tools such as whole-rock geochemistry and U–Pb and Lu–Hf analyses on detrital zircon grains can be deployed to unravel the provenance and tectonic setting of high-grade metasedimentary and metavolcaniclastic units. Here, we apply these analytical tools on samples from gneissic paleosomes of migmatites found in the eastern transition zone between the Neoproterozoic–Eopaleozoic Araçuaí and Ribeira orogens (southeastern Brazil). The studied paleosomes comprise peraluminous paragneiss rich in biotite, garnet and sillimanite, metaluminous hornblende-bearing gneiss free of peraluminous silicates, and intermediate terms between these compositions, all of them with geochemical characteristics pointing to sources located in magmatic arc systems. Overall, U–Pb data from detrital zircon grains bracket a maximum sedimentation age for all samples between 600 and 627 Ma, while εHf (t) : +5.7 to −18.7 and Hf T DM model ages of 1.0–2.2 Ga suggest moderately juvenile to evolved sources for the gneiss protoliths. However, despite the similarity in age range, the analyzed samples show contrasting isotope data indicating significant variability in the source areas. Sample 7 only has grains with negative εHf (−5.9 to −18.7), most of them ranging in age from 708 Ma to 758 Ma, with very few older (1021–1143 Ma) and younger (642–651 Ma) zircons grains, indicating evolved crustal sources of distinct ages (e.g., the Late Tonian – Early Cryogenian South Bahia Alkaline Province, the Early Cryogenian magmatism found in the West Congo Belt, the Stenian to Early Tonian Espinhaço and Matadi-Noqui igneous rocks, and magmatic rocks of the early Rio Doce arc). Conversely, sample 13 has twenty grains with positive εHf values and ages between 602 and 758 Ma, suggesting sourcing from (meta)igneous rocks of the Rio Negro arc and their remelting products, and forty grains with negative εHf values with ages between 591 and 646 Ma suggesting magmatic sources in the Rio Doce arc. Additionally, the two youngest spot ages (553 Ma and 571 Ma) have highly negative εHf values (−11.1 and −16.4) suggesting their origin from collisional anatexis. Similarly, sample 12 shows detrital grains within the consistent time interval (ca. 596 Ma – 798 Ma) of the Rio Negro arc and Rio Doce arcs, reinforcing that the fragments of these arcs, or zircons that were inherited from these terranes, are potential sources to the sedimentary protoliths of the paragneisses. The regional scenario together with our field and analytical data, compared with data available in the literature, suggest the sedimentary protoliths of the studied samples filled orogenic basins related to the Rio Doce magmatic arc. Most detrital zircon ages are close to the maximum depositional age, a classical signature of orogenic basins related to magmatic arcs. The studied paragneiss unit correlates with the Nova Venécia Complex, located on the intra-arc to back-arc zones of the Araçuaí orogen, and with the orogenic succession of the distal Andrelândia Group, shared by both the Araçuaí and Ribeira orogens. Furthermore, our data also suggest the juvenile Rio Negro - Serra da Prata arc system was either amalgamated with the Rio Doce arc or that fragments of these arcs were incorporated as unmelted xenoliths and xenocrystals within the Rio Doce arc rocks before ca. 614 Ma, providing key hints to unravel the evolution of the Araçuaí - Ribeira orogenic system (AROS) and its role in the Gondwana assembly. • Paragneisses from the Araçuaí-Ribeira Orogen sourced from Ediacaran arcs. • Maximum sedimentation age for all samples between 600 and 627 Ma. • Moderately juvenile to evolved sources (εHf (t) : +5.7 to −18.7, T DM = 1.0–2.2 Ga). • Elemental geochemistry coherent with graywackes from active margin settings. • Syn-orogenic basins related to the Rio Doce (G1 Supersuite) continental-margin arc. [ABSTRACT FROM AUTHOR]

The Cerro Uyarani Metamorphic Complex (CUMC) in Bolivia provides a record of complex Paleoproterozoic to Mesoproterozoic tectono-magmatic evolution, as revealed through U–Pb isotopic analysis of zircon from three litho-domains (DI – DIII). The Paleoproterozoic crystalline basement was subject to two stages of Mesoproterozoic reworking. This detailed study of zircon textures and geochronology, including determination of first Hf-isotope data, from felsic granulites, banded granulites and amphibolites reveals a first Paleoproterozoic event at 1.81–1.74 Ga in magmatic and some metamorphic zircon cores, with zircon ϵHf T values of +6.3 to −0.2. A subsequent Mesoproterozoic event can be divided into 2 cycles: a first one at 1.19–1.17 Ga is reflected by recrystallized rims and cores of zircon with ϵHf T values of −6.8 to −3.6. This cycle is here associated with migmatization of the basement, during which the Paleoproterozoic crust was differentiated into DI-leucosome rich migmatite, DII-leucosome rich migmatite, DIII – our best proxy of Paleoproterozoic crust, melanosome, and paleosome. The second cycle at ∼1.1–1.0 Ga is recorded in metamorphic rims and by newly grown metamorphic zircon with ϵHf T values of −15.1 to −2.6. This event was responsible for the transformation of the CUMC migmatitic basement into granulite facies rocks. We interpret that the CUMC was part of the southernmost portion of the Arequipa terrane from, at least, ∼1.74 Ga and that it then became attached to the Paraguá terrane and Amazon craton at 1.19–1.17 Ga. This collision generated migmatites, and then, with the arrival of Laurentia passing through the Arequipa terrane front (with CUMC at the Arequipa terrane), the conditions of metamorphism were raised to granulite facies. A younger event of lower metamorphic grade and likely associated with fluid-driven alteration is recognized in the partial retrograde transformation of mafic granulites into amphibolites. Our new U–Pb and εHf T data indicate that the Paleo-to Mesoproterozoic history of the CUMC is, thus, similar to that of the Arequipa terrane, Rio Apa terrane, the SW Amazon craton, and other Grenville-age inliers; but it was distinct from the evolution of the Sierra de Maz and Pie de Palo of the hypothetical MARA craton. • The Cerro Uyarani Metamorphic Complex (CUMC) witnessed multistage tectono-magmatic-metamorphic Paleo-to Mesoproterozoic events, similar with Arequipa terrane, Rio Apa terrane, SW of Amazon craton and Grenville inliers. • U–Pb and Hf-isotope data assign the first tectono-magmatic-metamorphic event with ages between 1.88 and 1.67 Ga. • Zircon textures indicate a second event distinguished by a first cycle of migmatization at ∼1.19 Ga and a second cycle of granulite metamorphism at 1.10–1.00 Ga; two reworking phases of Paleoproterozoic crust during the Mesoproterozoic. • U–Pb and Lu–Hf isotopic data reveals the association of the Cerro Uyarani Metamorphic Complex with the youngest events of the Grenville-Sunsas Orogeny. [ABSTRACT FROM AUTHOR]

This paper explores the sedimentary provenance of the Silurian to Devonian siliciclastic successions in the Central region of the San Juan Precordillera, in central-western Argentina. The comprehensive provenance analysis of the Tambolar Formation (upper Silurian), Talacasto Formation (Lower Devonian) and Punta Negra Formation (Lower-Middle Devonian) from the San Juan River section is based on petrography, detrital zircon analyses and combined U–Pb and Lu–Hf isotopic data. Modal composition of the three units here studied shows an evolution trend from quartzose recycled, mixed, to transitional arc. Detrital zircon morphologies indicate derivation from dominantly plutonic and metamorphic sources with little evidence of transportation. The most representative detrital zircon U–Pb age populations are Famatinian (middle Cambrian - Devonian), Pampean–Brazilian (Tonian - lower Cambrian), and Grenvillian (Ectasian - Stenian) cycles derived rocks. Hf isotopes determined mainly in Mesoproterozoic detrital zircons reflect a juvenile mantle source during crystallization, with less significant inputs from those with a crustal and recycled crust origin. Results from this work are compared to data from outcrops of the same units developed in the North-Central region of the Precordillera, presented in previous works. Provenance proxies provide insights regarding the correlation of probably equivalent units deposited in other foreland basins within the Cuyania terrane, such as the Villavicencio Formation (Mendoza Precordillera), Río Seco de los Castaños and La Horqueta Formations (San Rafael Block). The K–S test suggests a low correlation between the units studied at the San Juan River and the equivalent outcrops exposed towards the central and northern parts of the San Juan Precordillera, as well as with the known records of the Río Seco de los Castaños and La Horqueta Formations of the San Rafael Block. In contrast, the samples from the Villavicencio Formation show a high correlation with the sample from the Punta Negra Formation, indicating a possible common sediment source. The broad variations of U–Pb detrital age pattern distributions observed between Silurian and Devonian successions throughout the Precordillera and the San Rafael Block point to provenance shifts linked to variability in east-to-west sediment dispersal patterns within an axial peripheral foreland basin. Fluctuations in the sedimentary composition are ascribed to the differential exhumation rate of source rocks and a progression from a convergent tectonic setting in the San Rafael block towards a coeval collisional environment in the Precordillera. The Silurian - Early Devonian foreland basin is tectonically linked to the Ocloyic Orogen that resulted from the collision of Cuyania terrane to the Western margin of Gondwana. Source rocks were most likely located within the Mesoproterozoic basement of Cuyania, exhumed during the Middle Devonian as a response to the approximation of Chilenia. • A Provenance analysis, of the Silurian to Devonian Precordillera successions of the San Juan River section is here presented. • The approach of Chilenia to the west of Gondwana exhumed the basement rocks of the previously accreted Cuyania terrane, allowing erosion and sedimentation of their debris during Middle Devonian times. • Hf isotopes in Mesoproterozoic detrital zircons reflect a juvenile mantle source during crystallization. • Provenance proxies here presented indicate a lack of connection between depocenters of the Precordillera and the San Rafael Block. [ABSTRACT FROM AUTHOR]

A comprehensive study of the El Hornito Pluton, located in the Sierra Grande de San Luis (Argentina) is presented in this work. The intrusive body is a composite pluton constituted by four main units: 1) Granitic Porphyritic Unit, 2) Granitic Red Unit, 3) Granitic External Unit and 4) Mafic-Hybrid Unit. The main intrusive (granitic) units are crosscut by syn-magmatic felsic dikes. A Devonian age of 385 ± 2 Ma was obtained by U–Pb SHRIMP analyses on zircons belonging to the Granitic Porphyritic Unit. This age is considered representative of the El Hornito Pluton crystallization since the Granitic Porphyritic Unit is the most voluminous one. The Granitic Red Unit crops out in the central zone of the El Hornito Pluton and hosts the largest proportion of the rocks that comprise the Mafic-Hybrid Unit, where mingling/mixing processes are evident. The host rocks located in the western sector of the El Hornito Pluton present an intense contact metamorphism. Electron microprobe analyses of plagioclase, garnet, biotite, and muscovite in a garnet-sillimanite hornfels were performed to calculate thermobarometry from multireaction procedures in these hornfels, yielding P-T values of 3.7 ± 1.1 kbar and 626 ± 32 °C. These conditions are considered representative of the emplacement level of the El Hornito Pluton. The results of this study show that the El Hornito Pluton was emplaced at a depth of 14.1 ± 4.2 km, evidencing deeper crustal levels of emplacement than the Achalian granites of the Sierra de Córdoba. The age obtained in this work, along with others reported for the Sierras de San Luis and Córdoba, indicate that the intrusions occurred first in the west and later in the east. Moreover, according to the emplacement levels at which intrusions took place, different exhumation rates are proposed to have occurred across the orogen (in an NE-SW direction) after the Devonian magmatism, being greater in the Sierra de San Luis (southwest) than in the Sierras de Córdoba (northeast). • Petrology, geochronology, thermobarometry data and analysis of emplacement conditions of the El Hornito Pluton are reported. • Mingling-mixing processes dominate the central zone of the El Hornito Pluton. • There is a decrease in crystallization ages from SW to NE in Achalian plutons between 30° and 33.5° S. • The intrusion paleo-depths of Achalian plutons are greater in the Sierra de San Luis than in the Sierras de Córdoba. [ABSTRACT FROM AUTHOR]