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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 Nova Monte Verde metamorphic core complex is an arched structure located in the southern portion of the Rio Negro-Juruena geochronological Province and is part of a belt of metamorphic rocks containing gneiss and migmatite domes exhumed during Statherian extension of rifted Ventuari-Tapajós crust. This metamorphic core is bordered, both to the north and south, by felsic volcanic and plutonic rocks intensely foliated near the metamorphic core and becoming progressively undeformed as one moves away from the metamorphic core. U-Pb analyses of zircon and monazite from migmatites exposed in the core of the complex, coupled with a detailed structural analysis, enlighten the timing and duration of migmatite crystallization, indicating that crystallization, extensional deformation and exhumation of the core-complex were coeval. Analysis of a high melt fraction from migmatites outcroping near Bacaeri Farm suggest that the Nova Monte Verde metamorphic core complex records a history of neosome formation spanning at least 37 Ma, as indicated by 206Pb/238U ages (1800-1763Ma) for new zircon growth attributed to migmatization. Monazite from two samples yielded U-Pb ages of 1798 ± 29 Ma for the aluminous metatexite and 1754 ± 11 Ma for sillimanite-biotite metatexite. The former is interpreted as the metamorphic peak and main generation of leucosomes, and the latter as the second phase of partial melting or as an alternative, the timing of cooling and exhumation of metamorphic core complex. Crystallization of the Nova Monte Verde migmatites was therefore coeval in part with upper crustal extension and ductile flow of the mid-crust, suggesting that crustal anatexis was widespread over much of the mid-crust during Statherian time (∼1800-1760Ma). Therefore, the tectonic history of the Nova Monte Verde core complex involved regional extension and exhumation of high-grade metamorphic rocks by transtensional tectonics. The following results are at least more compatible with, if not suggestive of, a continental rift setting than the traditionally accepted continental arc setting. • Migmatites and the Statherian felsic magmatism is related to thermal perturbations in the upper mantle and mafic underplating. • Nova Monte Verde complex is a dome not related to subduction, and was exhumed during Statherian extension of rifted crust. • The crystallization, extensional deformation and exhumation of the Nova Monte Verde core-complex were coeval. • Migmatites of metamorphic core complex records a history of neosome formation spanning at least 37 Ma. [ABSTRACT FROM AUTHOR]

Abstract U-Pb and Lu-Hf isotopic studies were performed in igneous zircon crystals from orthogneisses, metagranodiorites and a gabbro of the Tumucumaque Complex, in Vila Nova region, south of Amapá state, Brazil. The complex is located in the southeastern region of the Guyana Shield, northeastern portion of the Amazonian Craton. The Tumucumaque Complex is represented by tonalitic to granodioritic gneisses and amphibolites, with subordinate metagranites and intrusive gabbros, metamorphosed in conditions of middle to Upper Amphibolite facies. The complex represent the basement of the metavolcano-sedimentary associations of the Vila Nova and Serra do Navio regions, and occur as NW-SE elongated domes. The contact of infra- and supracrustal rocks is defined by N45°-55°W-trending high-angle ductile shear zones. In this contribution we provide U-Pb zircon ages by LA-MC-ICPMS which attest for the presence of a broad area of Archean rocks in the Guyana Shield. In addition, we present stratigraphic relationships and structural data between the Tumucumaque Complex and the Rhyacian Vila Nova Greenstone Belt. The orthogneisses yielded zircon igneous ages of 2.851 ± 37 Ma and 2.852 ± 32 Ma and the metagranodiorites of 2.822 ± 33 Ma and 2.812 ± 17 Ma. Intrusive gabbro present age of 2.671 ± 46 Ma. The Lu-Hf data suggest an enriched mantle source and reworking of Paleo-archean crustal rocks. The results obtained suggest a magmatic orogenic episode during the Meso-archean (2.85–2.81 Ga) and a later Neo-archean (2.67 Ga) event, probably anorogenic. Highlights • The geochronological results suggest a broad Archean area in the study area. • Were identified two magmatic episodes, an Meso-archean and a Neo-archean. • The Lu-Hf data suggest an enriched mantle source and reworking of Paleo-archean crustal rocks. [ABSTRACT FROM AUTHOR]

The amalgamation of tectonic blocks during the Brasiliano/Pan-African orogeny has been the main subject of study of several works in recent years. From the integration of a diversity of data, including the geophysical potential data and a review of the provenance of metasedimentary sequences based on detrital zircons and the geochemistry of granitoids, the tectono-metamorphic evolution of the Northern segment of the Dom Feliciano belt is addressed. Results reinforce the similarities between the Brusque and Paranaguá terranes and the Itajaí-Perimbó Shear Zone as a major tectonic boundary. The kinematic model envisaged highlights the control of basement blocks in the present tectonic geometry of the orogenic belt. In this new model, modern South American coordinates are adopted as the reference frame, with the Curitiba terrane moving towards SSE and the Angola Craton towards NNW, with the Luís Alves terrane trapped in between. This kinematic model is corroborated by aeromagnetic and gravimetric data that highlighted the importance of the Itajaí-Perimbó Shear Zone as a major tectonic boundary in the northern segment of the belt, characterized as a suture zone separating two tectonic blocks with a distinct history of geodynamic evolution. The oblique collision between the blocks resulted on the development of a dextral transpression along Itajaí-Perimbó shear zone that is the main boundary between Luís Alves and Brusque terranes, the sinistral strike-slip Palmital Shear Zone that separates the Luís Alves and the Paranaguá terranes and by a frontal thrust, represented by the Icapara- Negra Shear Zone that bounds the already amalgamated block of the Luís Alves and Curitiba terranes from the outer Paranaguá terrane. [ABSTRACT FROM AUTHOR]

This paper presents the first Rb-Sr isotopic geochemistry study and SHRIMP zircon U-Pb dating in the Arroio Grande Ophiolite (southeasternmost Dom Feliciano Belt in Brazil), an extension of the Uruguayan Punta del Este Terrane. The metamafic units of the ophiolite show 87 Sr/ 86 Sr ratios ranging from 0.7036 to 0.7070 (recalculated at 630 Ma), which suggest a MORB magmatic source for the amphibolite protoliths and a volcanic magmatic arc source (with possible crustal contamination) for the metagabbro protoliths. Together, these features suggest a supra-subduction zone origin for these rocks, corroborating previous studies based on bulk-rock chemistry. In the metaultramafics, the 87 Sr/ 86 Sr 630 ratio of the chloritite sample (0.7152) is comparable to that of the Três Figueiras granite (0.7139), a syn-kinematic peraluminous granite related to the Ayrosa Galvão-Arroio Grande Shear Zone (which also affected the southern portion of the ophiolite, where the studied samples are located). The emplacement of the latter granite could be responsible for the metasomatism of the former serpentinites, generating talc- and chlorite-rich reaction zones. The SHRIMP U-Pb analysis of twelve chloritite zircons strengthens that assumption, as zircons with ca. 610-585 Ma (the age of the granite) were found in association with metasomatic microtextures. Zircon ages ranging from ca. 2000 to 660 Ma were also found in the chloritite. These latter ages are analogous to those found in the metasiliciclastic rocks that envelop the metaultramafic rocks of the ophiolite, so that the chloritite probably represents a blackwall reaction zone between (i) a former serpentinite, (ii) the Três Figueiras granite, and (iii) metasiliciclastic rocks. Additionally, we perform a SHRIMP U-Pb dating in a quartz-syenite melt, which are related to a tonalitic intrusion within the metasedimentary unit (the Matarazzo Marbles) of the ophiolite. The obtained concordia age of 640 Ma constrains the minimum age of ophiolitic mélange emplacement, as the tonalitic intrusion is related to continental arc magmatism (Pinheiro Machado Intrusive Suite). [ABSTRACT FROM AUTHOR]

The Apiaú Alkaline Complex (AAC) represents a rift-related intracontinental magmatism and occurs as intrusions within the Precambrian basement of the central-southern portion of the Guyana Shield, Amazonian Craton. The complex extends for over 200 km and comprises monzonites, syenites, nepheline syenites, nepheline-bearing syenites, trachytes and phonolites. It differs from other alkaline rocks of the craton both in age and tectonic setting. Here we report new petrologic, geochemical, and zircon and baddeleyite U-Pb geochronological information on the nepheline-bearing syenites and phonolites to discuss the petrogenetic and tectonic evolution of the AAC. Our new bulk rock major and trace elements analyses show that the complex is predominantly miaskitic, with potassic and sodic affinity, strong enrichment in light REE and negative Eu, Ba, Sr, P, and Ti anomalies. The phonolites and syenites geochemistry suggests similar fractionation processes from closely related parental melts for their genesis. Zircon and baddeleyite U-Pb crystallization ages of 111 ± 1 Ma and 116 ± 3, respectively, indicate a relationship between the alkaline magmatism and the opening of the Equatorial Atlantic Ocean. The spatial disposition of the alkaline rocks following major faults of the Amazonian Craton denotes a structurally controlled emplacement history by reactivation of ancient weakness zones. Crystallization ages are coincident with the Tacutu basin filling, evidencing a relative tectonic stability period and suggesting that the progressive subsidence contributed to the reactivation of the main structures in the region. The presence of inherited zircon from the orthoderived granitic basement (U-Pb ages of 1931 ± 4 Ma and 1958 ± 7 Ma) in a nepheline-bearing syenite, addition to petrography features and geochemical behaviour indicate that the alkaline magma was contaminated with Precambrian crustal rocks. [ABSTRACT FROM AUTHOR]

The Cuiabá Group is the basal part of the sequence of passive margin sediments that unconformably overly the Amazonian Craton in central Brazil. Despite these rock's importance in understanding Brazil's path in the supercontinent cycle from Rodinia to Gondwana and their potential record of catastrophic glaciation their internal stratigraphy and relationship to other units is still poorly understood. The timing of deposition and source areas for the subunits of the Cuiabá Group sedimentary rocks are investigated here using integrated U-Pb and Sm-Nd isotope data. We sampled in the northern Paraguay Belt, a range that developed in response to the collision between the Amazonian Craton, the Rio Apa Block, the São Francisco Craton and the Paranapanema Block. 1125 detrital zircon LA-ICPMS U-Pb ages were calculated and 22 whole rock samples were used for Sm-Nd isotope analysis. The U-Pb ages range between Archean and Neoproterozoic and the main source is the Sunsás Province. Moving up stratigraphy there is a subtle increase in slightly younger detritus with the youngest grain showing an age of 652 ± 5 Ma, found at the top of the sequence. The age spectra are similar across each of the sampled units and when combined with the Sm-Nd data, indicate that the source of the detritus was mostly similar throughout deposition. This is consistent with the analysis here that indicates sedimentation occurred in a passive margin environment on the southern margin of the Amazonian Craton. The maximum depositional age of 652 ± 5 Ma along with the age of the overlying cap carbonate of the Mirassol d’Oeste Formation suggests that part of this section of sediments were deposited in the purportedly global ∼636 Ma Marinoan glaciation, although we give no sedimentological evidence for glaciation in the study area. Compared to the southern Paraguay Belt where no direct age constraints exist, the glacial epoch could be either Cryogenian or Ediacaran. In addition, available data in the literature indicates a diachronous evolution between the northern and southern arms of the Paraguay Belt in the final stages of deposition and deformation. [ABSTRACT FROM AUTHOR]

Pyroclastic levels are descripted in Sierras Australes outcrops and Claromeco Basin sub-surface records, interbedded with mudrocks and coal beds in the base of the Tunas Formation sequence that correspond to the Permian South West margin of Gondwana. The pyroclastic levels classify as fine tuff. SHRIMP zircon ages obtained are 291.7 ± 2.9 Ma in the outcrop and 295.5 ± 8.0 Ma in the subsurface. These ages are consistent with other zircon SHRIMP ages of other outcrops tuff of the Tunas Formation, with Permian flora, and with tuff ages of correlated Gondwana areas, in the Paraná, Karoo and Paganzo basins. These data, in addition with other geological evidences, support a tectonically active and changing environment during the Permian of Gondwana. The ages allowed calculating a northward latitudinal speed of 2.7 cm/year for Gondwana during the Permian. This latitudinal movement is explained as the consequence of the final coupling of several continental microplates, gradually amalgamated from the southern margins of Gondwana and from the northern of Laurentia to configure the final Pangea during the Triassic. Since the main accretions in the southwestern margin of Gondwana could have started during the Devonian - Carboniferous, this Permian orogeny (San Rafael Orogenic Phase in Argentina) would be representing the post - collisional deformation, with a peak of compression in the Early Permian that was attenuating towards the foreland during the Late Permian - Early Triassic. With these results, it is also possible to constraint the age of the upper Paleozoic glaciation up to 295, previous to the deposition of the Tunas Formation in the Sauce Grande Formation. [ABSTRACT FROM AUTHOR]

New geologic and geochronologic data of Paso del Dragón Complex (PDC) located at Northeastern Uruguay is analyzed. Two lithodemic units are described and characterized, La Micaela Schists and Cerro La Tuna Serpentinites. La Micaela Schists represent 80% of PDC and it comprises a meta-volcano-sedimentary succession poly-deformed, composed by muscovite-quartz-feldspathic schists, quartzites, and felsic meta-volcanic rocks. Cerro La Tuna Serpentinites represents 20% of PDC and it comprises mafic-ultramafic rocks, also deformed and metamorphosed, composed by serpentinites, varied magnesian schists, hosted by La Micaela Schists. The complex is hosted to the north and west by the Granitic belt of the Dom Feliciano Belt that includes poly-intrusive plutons known from south to north as Aiguá, Cuchilla Dionisio and Sierra de los Ríos batholiths classified as high-K calc-alkaline pre-to post-collisional granitoids. Relevant U–Pb LA-ICP-MS analyses of metamorphic/detrital zircon grains from migmatitic-gneissic basement suggest an age of ca. 668 Ma for the metamorphic event associated with the migmatization process. The deposition and metamorphism age for La Micaela Schists lithodeme are ca. 590 Ma and 570 Ma respectively. The Complex is interpreted as remains of sedimentary and magmatic units generated in an arc-related environment tectonically emplaced within the granites. Their generation, deformation and metamorphism, mainly of Ediacaran age, are associated to the Western Gondwana assembly. This thrust sheet could be regarded as a dismembered ophiolite as previously suggested by other authors. Finally, it is proposed the correlation between Cerro Olivo Complex of Punta del Este Terrane and the migmatitic-gneissic basement of Paso del Dragón Complex based on their similar zircon U-Pb age patterns. Also, it is suggested that Cerro Olivo Complex of Punta del Este Terrane and the Granitic belt might be the main detrital sources for La Micaela Schist. [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]

This study investigated the bulk sediment geochemistry, U–Pb ages and rare earth element (REE) geochemistry of one hundred detrital zircons recovered from the Brujas beach sands in southwestern Gulf of Mexico to understand the provenance and age spectra. The bulk sediments are high in Zr and Hf contents (∼1400–3773 ppm and ∼33–90 ppm, respectively) suggested the abundance of resistant mineral zircon. The chondrite normalized REE patterns of the bulk sediments are less fractionated with enriched low REE (LREE; La CN /Sm CN = ∼491–693), depleted heavy REE (HREE; Gd CN /Yb CN = ∼44–69) and a negative Eu anomaly (Eu/Eu ∗ = ∼0.44–0.67) suggested that the source rock is felsic type. The results of this study revealed highly varied contents of Th (∼4.2–321 ppm), U (∼20.7–1680 ppm), and Hf (∼6970–14,200 ppm) in detrital zircons compared to bulk sands. The total REE content (∼75 and 1600 ppm) and its chondrite-normalized pattern with positive Ce and negative Eu anomalies as well as low Th/U ratio of zircon grains indicated that they were dominantly of magmatic origin. U–Pb data of zircons indicated two age populations, with predominance of Permian-Triassic (∼216–286 Ma) and Neoproterozoic (∼551–996 Ma). The Permian-Triassic zircons were contributed by the granitoids and recycled metasedimentary rocks of the Chiapas Massif Complex. The major contribution of Neoproterozoic zircons was from the Chaucus, Oaxacan, and Chiapas Massif Complexes in Grenville Province, southern Mexico. U–Pb ages of zircons from the Brujas beach are consistent to the reported zircon ages from the drainage basins of Usumacinta, Coatzacoalcos, and Grijalva Rivers in southern Mexico, suggesting that the sediments delivered by the rivers to the beach area are vital in defining the provenance of placers. [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]

U Pb LA-ICPMS geochronological analyses were carried out on zircon grains from metavolcanic rocks of the Bossoroca Complex and for one ash tuff of the Acampamento Velho Formation of the Camaquã Basin, in order to understand the evolution of the Neoproterozoic São Gabriel magmatic arc. A total of 42 analyses of igneous zircon grains were performed in three samples. The results yielded U Pb ages of 767.2 ± 2.9 Ma for the metavolcanic agglomerate (BOS-02); 765 ± 10 Ma for the metacrystal tuff (BOS-03) and 565.8 ± 4.8 Ma for the ash tuff (BOS-04). The Orogenic Cycle in Brazil is characterized by a set of orogenic belts consisting of petrotectonic associations juxtaposed by two collisional events that occurred at the end of the Neoproterozoic. In southern Brazil this orogeny formed the Dom Feliciano Belt, a unit composed of associations of rocks developed during two major orogenic events called São Gabriel (900–680 Ma) and Dom Feliciano (650–540 Ma). The main São Gabriel associations are tectonically juxtaposed as elongated strips according to the N20–30°E direction, bounded by ductile shear zones. The Bossoroca Complex comprises predominantly metavolcano-sedimentary rocks, characterized by medium-K calc-alkaline association generated in a cordillera-type magmatic arc. The volcanism occurred in sub-aerial environment, developing deposits generated by flow, resurgence and fall, sporadically interrupted by subaqueous epiclastic deposits, suggesting an arc related basin. The São Gabriel Terrane contains the petrotectonic units that represent the closure of the Charrua Ocean associated to the subduction period of the Brasiliano Orogenic Cycle in the Sul-rio-grandense Shield. [ABSTRACT FROM AUTHOR]

The Porongos Group is the major component of a fold and thrust belt located in the central portion of the Dom Feliciano Belt in the Sul-Riograndense Shield, Brazil. In this paper, the variations in composition of sediments and the depositional time are presented. Major and trace elements indicate that Porongos Group is composed mostly of immature sediments derived from intermediate felsic sources with minor contribution from mature recycled sources. U–Pb SHRIMP ages for a chlorite schist (sample 300) exhibit a proeminent population of 570–800 Ma, subordinate population of 1800–2250 Ma and minor population of 1200 Ma, whereas for a schist (sample 198) the main population is 1050–1500 and minor populations are 2040–2300 and 580–800 Ma. The εHf values of Neoproterozoic grains indicate variable degrees of crustal reworking (εHf = −18 to −4) with three main T DM model ages (2.2, 1.8, 1.5 Ga). The Paleoproterozoic grains include a few Archean (3.2–2.5 Ga) T DM ages. The trace elements of all analyzed detrital zircon grains reflect continental crust origin. According to the data set, the sediments of the Porongos Group were derived from locally eroded granitic rocks of the Dom Feliciano Belt and from the uplifted Paleoproterozoic basement (La Plata Craton). Further analytical signal and total magnetic field maps delimit regionally the shape and extension of the Porongos fold and thrust belt and includes the Capané region. We conclude that the duration of Porongos Group basin filling probably lasted from 650 to 570 Ma in a foreland tectonic setting of the Dom Feliciano Belt. [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]

The application of Fission-Track Thermochronology (FTT), and U-Pb and Lu-Hf isotope analyses on the same zircon grains revealed the provenance and thermal/tectonic events related to the build-up and evolution of the Bauru Basin filling in Minas Gerais, Brazil. The U-Pb on detrital zircon reveals that the potential source areas were dominated by Brasiliano outcrops and subordinately, Paleoproterozoic, Mesoproterozoic, and Carboniferous sources. Positive εHf(t) signatures can characterize the Goiás magmatic Arc and older adjacent terranes as the most probable region that supplied the Bauru Basin. The FTT data display five main age peaks at 569, 337, 235, 132, and 83 Ma. They record the exhumation and denudation processes of Brasiliano and Gondwanide orogens and later, the Serra Geral magmatism of the South American Platform. A younger subordinate age (100–80 Ma) is recorded, and it may be associated with intense alkaline magmatism that occurred during the initial stages of basin deposition. • FTT, U-Pb, and Lu-Hf analyses unraveling the provenance and thermal/tectonic events in the Bauru Basin, Brazil. • The FTT data have five main age peaks at 569 Ma, 337 Ma, 235 Ma, 132 Ma, and 83 Ma. • The combined U-Pb and Lu-Hf detrital zircon dating suggest potential source areas for the Bauru Basin deposits. • Positive and negative εHf(t) values suggest source rocks of the Brasilia Belt and Goiás Magmatic Arc for the Bauru Basin. [ABSTRACT FROM AUTHOR]

In this contribution, we present the stratigraphy of the igneous and metamorphic rocks of the Taquetrén Range, a sector located in the southernmost margin of the North Patagonian Massif (42°42′00″ S - 69°30′00″ W). Its igneous and metamorphic basement is composed of the newly defined "Lagunita Salada Igneous-Metamorphic Complex" (LSIMC), "Paso del Sapo Plutonic Complex" (PSPC) and "Sierra de Taquetrén Plutonic Complex" (STPC). The LSIMC comprises gneisses, schists, amphibolites and migmatites, which share a S 1 –S 2 penetrative foliation with a mean orientation of 300°–330°/40°–60° NE. Based on mineral paragenesis, metamorphic conditions of these rocks are the result of Barrovian-type metamorphism in the upper amphibolite to granulite facies. EPMA Th–U–Pb ages of monazites display two isochron main populations at 379 ± 5 Ma and 323 ± 5 Ma, which suggest long-term high-temperature conditions for the region between Late Devonian and Carboniferous times. The Complex is intruded by concordant tonalites, granodiorites, porphyric granites and minor pegmatites and felsic dykes, which are grouped in the PSPC. Both the LSIMC and PSPC are intruded by unfoliated peraluminous granitoids grouped in the STPC. Based on field and microstructural data, the pervasive foliation identified in the PSPC was caused by processes ranging from magmatic flow to solid-state deformation, indicating a syntectonic emplacement. Zircon U–Pb analysis by LA-ICP-MS in the PSPC shows two distinguishable groups with concordia ages of 314.1 ± 2.2 Ma and 302.8 ± 2.2 Ma, interpreted as the crystallization and subsequent deformation age respectively, related to protracted high-strain conditions. The outcrops in this area represent an almost full tectonic cycle encompassing from medium-high grade metamorphic rocks and syn-tectonic intrusions to post-tectonic intrusions, therefore configuring a key locality for the analysis of North Patagonian Paleozoic evolution. Moreover, based on the compilation of U–Pb zircon ages, a ~20 My magmatic gap period (360-340 Ma) is recognized in the southwestern margin of the North Patagonian Massif coeval with amphibolite-granulite facies metamorphism in different sectors of the Central Patagonian Igneous-Metamorphic Belt, presenting thus important implications for the tectonic evolution of the area. • One Igneous-Metamorphic Complex and two Plutonic Complexes are defined in Taquetrén Range. • Amphibolite-granulite facies metamorphism at 379 ± 5 and 323 ± 5 Ma (EPMA Th–U–Pb). • Syntectonic magmatism at 314.1 ± 2.2 and 302.8 ± 2.2 Ma (LA-ICP-MS U–Pb). • A ~20 My magmatic gap for Late Devonian – Early Carboniferous times is identified. [ABSTRACT FROM AUTHOR]

The Contendas-Mirante metavolcano-sedimentary sequence (CMS) has been studied by diverse authors but they did not emphasize the petrogenesis of the granitoid rocks that occur in the area. A set of eight fine-to-medium grained granitic plutons intrude the 3.2–3.4 Ga TTG rocks from the Gavião Block (GB) as well the 2.09–2.17 Ga meta-sedimentary rocks of the Contendas-Mirante metavolcano-sedimentary sequence. Two mineral assemblages were identified: i) quartz, K-feldspar, plagioclase and biotite as main phases and muscovite, zircon, apatite, chlorite, sericite, ilmenite and magnetite as accessories and ii) quartz, K-feldspar, plagioclase, biotite and muscovite as main phases and zircon, apatite, chlorite, sericite and ilmenite as accessories. Thus, it was possible to divide them between biotite-monzogranites and two-mica granites. Our results reveal that these granitoids are sodic and potassic peraluminous, leucocratic, calc-alkalic to alkali-calcic and are enriched in LREE in relation to the HREE. The biotite-monzogranites have slightly negative Eu anomalies whereas the two-mica granites portray pronounced negative Eu anomalies. Both biotite-monzogranites and two-mica granites have Zr/Hf ratios between 21.90 and 35.59 which allowed their classification as moderately-to-highly fractionated granites. The biotite-monzogranites show geochemical similarities with Archean TTGs while the two-mica granites are akin to the Post-Archean granitoids. The Rb and Y + Nb values indicate that the biotite-monzogranites are syn-collisional and the two-mica granites are post-collisional. The Rb/Sr and Rb/Ba ratios allowed the distinction of between clay-poor sources, related to the biotite-monzogranites and clay-rich sources related to the two-mica granites. U–Pb geochronological analysis indicated that the biotite-monzogranites have U–Pb concordia age of 2003 ± 10 Ma whereas the two-mica granites portray U–Pb concordia age of 2056.7 ± 14 Ma, suggesting that both are Paleoproterozoic. Lu–Hf isotopic analysis in zircon showed that both granites have negative ƐHf(t) values (−33.5 to −8.1 for the biotite-monzogranites and −26.3 to −7.4 for the two-mica granites) which evidences their crustal origin. The biotite-monzogranites have T DM2(Hf) varying between 2.99 and 3.98 Ga while the two-mica granites have T DM2(Hf) between 3.02 and 3.64 Ga, suggestive of their derivation from Archean source rocks. • The granites that intrude the CMS are moderately-to-highly fractionated biotite-monzogranites and two-mica granites. • Biotite-monzogranites have zircon U–Pb ages of 2003 ± 10 Ma and the two-mica granites have zircon U–Pb ages of 2056.7 ± 14 Ma. • ƐHf(t) values between -26 and -7 (bt-monzogranites) and -33 and -8 (two-mica granites), indicating their crustal origin. • Bt-monzogranites are derived from clay-poor Archean sources while two-mica granites portray clay-rich Archean sources. [ABSTRACT FROM AUTHOR]

The Suri Formation is a sedimentary-volcanic succession in the Famatina belt formed during Lower - Middle Ordovician arc magmatism along the western margin of Gondwana. This study reports new lithostratigrafic data relating to the Suri Formation in the Chaschuil valley (Catamarca). The survey defines the main characteristics of volcanism and sedimentation through facies analysis. Epiclastic, volcaniclastic, pyroclastic and peperitic facies were recognized and interpreted in five facies association. The features and relationships of the facies associations indicate environments such as apron volcaniclastic, inner to an outer shelf, and fan distal delta, interbedded with effusive and explosive volcanism. Volcanic activity and relative sea-level changes were controls on sedimentation style in basins adjacent to the volcanic edifice. The study reports U–Pb geochronological analysis of zircon from a sandstone sample of the Suri Formation to infer detrital provenance. The detrital zircon pattern with peaks at 486 Ma points to active Famatinian magmatism as recorded on the nearby Narváez batholith. Eruptive masses experienced rapid reworking, short sedimentary transport and intra-arc deposition. The maximum deposition age of detrital zircon corresponds to a subordinate age cluster at 464.4 ± 4.4 Ma and reflects synchronism between volcano-sedimentary deposition in the Suri Formation and plutonic-volcanic construction of the Las Planchadas Formation. • This study reports a stratigraphic analysis of the Suri Formation in the northern Famatina System. • The Suri Formation reflects apron volcaniclastic, internal to external shelf and fan distal delta. • Variable intensity of volcanism controlled the sedimentary environment of Suri Formation. • Volcanic facies contain abundant proximal deposits suggestive of explosive eruptive activity. • Sedimentation of the Suri Formation reveals a topographic surface with high slope gradient. [ABSTRACT FROM AUTHOR]

The Antimonio depositional system ranges from the Upper Permian to the uppermost Lower Jurassic. It is the only locality of Upper Triassic shallow marine carbonates in Mexico and through its speculative basement; it provides a potential link between the terrane framework of Mexico and the North American Cordillera. Various paleotectonic models have been proposed to explain the mixed siliciclastic-carbonate successions of the Antimonio depositional system in Sonora, Mexico, including interpreting it as a distinct allochthonous terrane or having a position close to the Laurentian basement. Microfacies, paleontological and paleomagnetic studies have suggested a paleogeographic position in low latitudes close to Laurentia. However, the basement structures of the Antimonio depositional system are poorly known and have numerous uncertainties. Here, we use detrital zircon geochronology to identify the sources of terrestrial sediments of the Antimonio depositional system and to propose potential sedimentary distribution patterns. The results allow us to clarify its paleotectonic position and consolidate the geodynamic model of González-León et al. (2005), in which the Antimonio depositional system was attached to the Caborca block. Four major zircon age distributions of detrital zircon were determined in the Barra los Tanques and Sierra del Álamo sections of the Rio Asunción Formation (Antimonio depositional system: (1) a Permo-Triassic group (207–292 Ma); (2) the group/population of 1.0–1.2 Ga; (3) a group clustering between 1.3 and 1.5 Ga and (4) the group of 1.6–1.8 Ga. This new data set was compared with published detrital zircon data from localities along the North American Cordillera, using two-sample Kolmogorov-Smirnov tests and hierarchical clustering. The results allow us to identify potential sources located in the Cordilleran continental arc and the ancestral Rocky Mountains, as well as in sediments and volcanic deposits of their respective surrounding areas. We suggest that the transport for these sediments was likely provided through the Chinle river system, and long-shore oceanic currents. Combining published data from Magsat magnetic anomalies with stratigraphy based paleontology, and our new geochronological data analysis, we suggest that the Antimonio depositional system must have been part of Laurentia and potentially linked to the Caborca block during the Late Triassic. [ABSTRACT FROM AUTHOR]

The present work contributes with new data to better understand the geology and spatial distribution of the alteration and mineralization events, as well as new U–Pb zircon ages, that allow elucidating the magmatic history of the La Caridad Vieja mineral deposit, which is part of the porphyry Cu–Mo system from La Caridad mine, northwest Mexico. Mineralization is hosted in a sequence of volcanic rocks from the Late Cretaceous-Paleocene Tarahumara Formation and is associated with the emplacement of quartz monzonite stocks, which intruded to volcanic rocks. Detailed studies based on petrography, XRD, SEM and SWIR, indicate that the La Caridad Vieja is characterized by a zone of phyllic alteration dominated by qz-ser in the deepest parts, and it is associated with molybdenite + chalcopyrite + pyrite + galena + sphalerite, with values ranging from 0.1 to 0.9% Cu and <0.02% Mo. Above the phyllic alteration zone, there is an intermediate argillic alteration zone (quartz + kaolinite + halloysite + smectite + illite), mainly with pyrite. In specific areas, advanced argillic alteration is observed (alunite + pyrophyllite + dickite + kaolinite + halloysite) accompanied by pyrite + enargite + famantinite + barite. The new U–Pb radiometric ages in zircons indicate an age of 54.71 ± 0.39 Ma for the upper part of the Tarahumara Formation, while a sample of the mineralizing stock yielded 51.95 ± 0.48 Ma. The results of this investigation suggest that La Caridad Vieja corresponds to a portion of the upper part of the Cu–Mo porphyry of La Caridad, which was downthrown by the La Caridad fault, during the Basin and Range extensional event in the Miocene. The reconstruction of the geological model suggests that La Caridad Vieja corresponds to the transitional zone between the Cu–Mo porphyry and an epithermal high sulfidation mineralization zone, which was eroded. Prior to the dislocation caused by the La Caridad fault, the eroded area was covered by a ferruginous conglomerate overlain by rhyolite flows dated at ~24 Ma. On the other hand, geochronological data suggests that the mineralizing event at La Caridad Vieja, although it is contemporaneous with the porphyry system of the La Caridad mine, it continued in this area at least until ~52 Ma. • The La Caridad Vieja mineralized area corresponds to the upper portions of the La Caridad porphyry Cu–Mo system. • Hydrothermal alteration assemblages and mineralization at the La Caridad Vieja area indicate the transition between porphyry Cu–Mo and HS epithermal systems. • Detailed geological, alteration mapping and SWIR analyses define the temporal and spatial distribution of hydrothermal alteration zones of the La Caridad Vieja area. • U–Pb zircon ages suggest that the magmatic-hydrothermal mineralizing event remained active in the La Caridad Cu–Mo porphyry system until at least ~52 Ma. [ABSTRACT FROM AUTHOR]

Isotopic Lu-Hf and U-Pb systematics can provide important insights into the tectono-metamorphic processes that occurred in the source regions of sedimentary/metasedimentary units, helping to further clarify regional crustal evolution. The studied metasedimentary sequence is located in the southern Brasília Orogen, SE Brazil, a fold-and-thrust belt composed of a thick nappe stack transported towards the southern São Francisco Craton (SFC) during the Neoproterozoic. Adjacent to the Cratonic border is a reworked Neoproterozoic metasedimentary passive margin sequence, that includes the Carrancas succession, for which we present new U-Pb and Lu-Hf detrital zircon analyses (ca. 700 grains in total). Results yielded a maximum depositional age of 0.988 ± 0.013 Ga and an extensional tectonic setting for the precursor basin. Major source areas, constrained by comparing our data to isotopic analyses compiled from the existing literature, are probably located in the adjacent southern SFC. Lu-Hf analyses of Paleoproterozoic and Archean zircon grains, presented in this study, yielded similar results to those obtained for the basement of the SFC. However, important U-Pb age peaks found in this study do not have strong correlatives in the southern SFC (e.g. 1.84,1.87 and 1.88 Ga), with the exception of a few localized examples (e.g. Espinhaço I magmatism). These ages are abundant in the southwestern Congo Craton (CC), which was potentially relatively close to the studied area during sedimentation, since the SFC and CC probably constituted a single continental mass after the Paleoproterozoic until the opening of the south Atlantic in the Mesozoic. • U-Pb and Lu-Hf detrital zircon analysis. • Neoproterozoic (ca. 980 Ma) passive margin succession of the São Francisco Craton. • Lithostratigraphic repetition of formations due to folding corroborated by isotopic analyses. • Provenance assessment: the São Francisco and Congo cratons as likely sources. [ABSTRACT FROM AUTHOR]

The relationship between plutonic and volcanic rocks is key to understanding the geochemical evolution of silicic magma systems. In order to untangle the plutonic and volcanic connection and contribute to the reconstruction of the Lower Paleozoic Arc at the SW Gondwana margin, in this study we describe the Sey Plutonic-Volcanic Unit, located in Eastern Magmatic Belt, northern Puna, Argentina. Additionally, we present zircon U-Pb ages by LA-MC-ICP-MS and geochemical data. The studied unit is comprised of monzogranites, granodiorites, gabbros, dacites, and rhyodacites, cropping out as plutonic bodies, laccoliths, sills, subaqueous domes, and lava flows. Following the analyses of the different zircon age populations, the granodiorites bodies crystallized at ∼480 Ma, the monzogranites followed at ∼470 Ma. Lastly, the rhyodacites crystallized at ∼446 Ma. Afterward the age groups analyses, in the Eastern Magmatic Belt, northern Puna, the magmatic activity started from ∼520 to 515 Ma until ∼446 Ma, with the magmatic activity peak at ∼485-475 Ma. The age groups, besides with the geochemistry data, isotope, and magma source similarities of the Eastern Magmatic Belt, both north and southern Puna, underline that the formation of the granitoids and volcanites in the Eastern Magmatic Belt was perhaps through a long-lived magmatic event, represented by low and high volume magmatic episodes. Image 1 • The Sey Plutonic-Volcanic Unit started its magmatic activity from ∼520 to ∼446 Ma. • The magmatic activity peak in this unit was at ∼485-475 Ma. • The Eastern Magmatic Belt was formed by a long-lived magmatic event. [ABSTRACT FROM AUTHOR]