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This paper presents pathological lesions in the osteoderms of three extinct pampatheres: two specimens of the genus Holmesina sp. and one specimen of Pampatherium humboldtii, which lived in the Brazilian Intertropical Region. The traces analyzed here were attributed to the ichnospecies Karethraichnus minimum and were associated with the behavior of ectoparasites, such as fleas, likely belonging to the genus Tunga. Some osteoderms also present ulcerative lesions, possibly generated by the action of microorganisms such as bacteria and fungi. These new records expand our knowledge about the paleopathologies caused by fleas in extinct pampatheriids, demonstrating that such occurrences were common. • Occurrence of Karethraichnus minimum in osteoderms of three extinct pampatheres. • Ulcerative lesions derived from flea lesions was observed. • Increase of knowledge about the paleopathologies in extinct pampatheriids. [ABSTRACT FROM AUTHOR]

This paper presents the relationship between environmental and anthropic factors, long-term dunefield migration, as well as sediment budget and overpassing process at Santinhos-Ingleses dunefield, in Southern Brazil. The study is based on two-decade (2002–2023) topographic data, meteorological and satellite images (for vegetation, urbanization and dune migration assessment). An analysis of historical rainfall data reveals a consistent rise in annual average precipitation, the events often correlated with north winds, which had lower average speeds compared to the stronger south winds. This, as the primary force driving the northward migration of the dunefield, has decreased, and the drift potential diminished. During rainy days, aeolian transport is limited as the sand becomes moistened, facilitating vegetation growth (approximately 10% between 2014 and 2023). The PDO average index (2002–2023) highlighting two distinct patterns: positive periods accounting for 18% and negative periods for 82%. These patterns have significant implications for sediment volume and rainfall variability in the region. Urban expansion, estimated at around 12% during this interval, emerges as a significant factor in the system. The northern part of Santinho's embayment features a flatter, wider, and more stable compared to the southern part. The higher energy levels in the surf zone facilitate aeolian sediment transport to the beach, which is crucial for the initiation of the transgressive dunefield. Additionally, the lower topography behind the foredune, contrasting with the higher elevation further inland, increases sediment accumulation and transport. The topography data shows consistent sediment input values over the last decade (2014–2023), ranging from 6000 to 7000 m³/year. In contrast, sediment supply values during the same period average around 8000 m³/year. Consequently, the sediment overpassing Santinho's foredune towards Ingleses beach results in a negative sediment balance in the dunefield system. • Topography decadal data collected with DGPS. • Relationship between environmental and anthropic factors with dunefield migration. • Sediment budget and overpassing at Santinho and Ingleses beach, southern of Brazil. • Negative sediment balance in the dunefield system. [ABSTRACT FROM AUTHOR]

In central-western Argentina, an Early Paleozoic belt including mafic-ultramafic bodies and marine metasedimentary rocks occurs along the western margin of the Precordillera and in the eastern Frontal Cordillera. In this paper, we present the analysis of aeromagnetic data and its processing focused on mapping geological limits, structures and the relation at depth of the southern Precordillera. With this main objective were applied filtering algorithms, reduction to the pole, tilt derivative, analytic signal, and particularly, the use of Improved Logistic Function (IL) as a new method of edge detection, in combination with the inversion map obtained from the Magnetization Vector Inversion (MVI) method. The results allow us to describe at depth the main trend of the Southern Precordillera Mafic Ultramafic Belt as two separated bocks, one in Peñasco and another in Cerro (Co.) Cortaderas, passing through Cerro (Co.) Pozos with a possible NNE-SSW direction. The combination of this techniques also can be used as prospecting guide to Pb–Zn–Ag vein deposits and High sulfidation Au-Epitermal deposits. • Determination of the Precordillera Mafic-Ultramafic Belt. • Linkage of maximum susceptibility, IL filter, outcrops of Mafic Ultramafic rocks and structural lineaments. • Magnetic Susceptibility 3D Model. [ABSTRACT FROM AUTHOR]

One of the challenges in the unification of the global vertical datum is to determine the vertical offset between the local vertical datum and the global vertical datum. Since 2015, the scientific community has been working on the unification of the global vertical datum, following the publication of the resolution for the definition and realization of an International Height Reference System. This paper aims to estimate the vertical offset in Brazil (Imbituba and Santana Data) by combining a regional gravity field model, using the Geodetic Boundary Value Problem approach applying the Remove-Compute-Restore procedure, and GNSS/leveling data. In the Imbituba vertical datum 1271 stations were used and 66 stations were connected to the Santana tide gauge. The results showed that the geopotential value of Imbituba was 62,636,849.87 ± 0.224 m2s-2, and the vertical offset concerning the reference surface (W 0) was 0.358 ± 0.023 m. In Santana, the geopotential value was 62,636,836.88 ± 4.108 m2s-2, and the vertical offset was 1.689 ± 0.420 m. The offset between Imbituba and Santana was computed once the physical connection between Brazil's two local vertical data is a challenge. The estimated value was 1.331 ± 0.421 m. This means the Santana vertical datum is 1.331 m higher than the Imbituba vertical datum. • Improving the Brazilian height system. • Using GNSS/leveling data to estimate the vertical offset in Brazil. • Connecting the Brazilian local vertical data to the International Height Reference Frame. [ABSTRACT FROM AUTHOR]

Turritelline gastropod-dominated assemblages (TDAs) are common in siliciclastic facies from the mid-Cretaceous to the Recent, but their distribution in carbonate facies has been thought to be limited to the Cretaceous and Paleogene, except for "cool-water" carbonates from the Miocene of Australia. This paper describes a TDA in a Pliocene limestone in northern Chile, the only known Neogene TDA limestone from outside Australia. This Chilean TDA probably formed in conditions of relative low temperatures and high productivity, and thus appears to support the hypothesis that TDAs largely disappeared from warm waters after the Oligocene. It is also possible, however, that it formed in conditions of warmer temperatures associated with upwelling during the Early Pliocene warm interval. • A turritelline gastropod-dominated assemblage from Chile is Early or Late Pliocene. • The limestone assemblage is a rarity in the Neogene, when most are in siliciclastics. • The assemblage formed under high-productivity conditions. • If Late Pliocene, conditions were cool water upwelling, unusual for a limestone. • If Early Pliocene, they were non-uniformitarian warm water upwelling in a warm ocean. [ABSTRACT FROM AUTHOR]

The Afonso Cláudio Intrusive Complex (ACIC) is a typical post-collisional intrusion from Araçuaí-West Congo orogen (AWCO). The ACIC intruded allanite-bearing orthogneisses from AWCO pre-collisional tectonic stage (Rio Doce arc related rocks) and paragneisses from Nova Venécia Complex and it is composed of two lowered off-centered monzogabbroic and monzodioritic cores surrounded by quartz monzonite high hills, showing intense magma mingling and mixing between these domains. Xenoliths attributed to the enclosing gneisses have been commonly found widespread in the quartz monzonitic rocks, while are occasional in the monzogabbroic and monzodioritic domain. This paper presents the first detailed investigation of the xenoliths hosted by an AWCO post-collisional intrusion, focusing on petrography, major and trace element geochemistry and U–Th–Pb monazite dating of the main xenolith types. For comparison, major and trace element data investigation of the ACIC enclosing rocks has also been conducted. The correlated xenoliths and ACIC enclosing rocks show partially similar geochemical features, however both show different REE and multi-element normalized patterns compared to the ACIC main rocks. These results suggest that correlated xenoliths and enclosing rocks are cogenetic, however both could not represent the main sources of magmas that generated the ACIC. Geochemical modeling of igneous processes of previous ACIC dataset considering the investigated xenoliths and enclosing rocks as the main assimilant material suggests that mixing was responsible for both ACIC main rocks similar geochemical patterns and linear trends in the bimodal diagrams. This modeling also indicates that the evolution of the ACIC main rocks was ruled by different processes. Fractional crystallization with minor influence of assimilation of enclosing rocks controlled the magmatic evolution of monzogabbro and monzodiorite related to an enriched mantle source, while coupled assimilation and fractional crystallization ruled the evolution of quartz monzonite possibly associated to lower crust magmas mainly contaminated by enclosing rocks. U–Th–Pb monazite dating of two xenoliths showed that these rocks preserved similar main ages related to different stages of ACIC and AWCO post-collisional evolution. Both xenoliths showed main older ages of 478 and 477 Ma which are related to ACIC intrusion during AWCO post-collisional stage, while younger ages of 431 and 427 Ma are probably related to the intrusion of syenogranite dykes that crosscut the ACIC, representing an extension of AWCO post-collisional magmatism or a later unrelated thermal event. Due to the similarities between the typical AWCO post-collisional intrusions, the insights brought about the evolution of ACIC magmas could be considered to the typical AWCO post-collisional mantle and crustal magmas. This first investigation of xenoliths hosted by an AWCO post-collisional intrusion has showed that these strange rock pieces could bring new and important insights about the AWCO evolution, which shows an amazing and long-lasting magmatism with common occurrence of poorly investigated xenoliths. • The ACIC is formed by the interaction between mantle and crustal contrasting magmas. • The contrasting magmas evolved ruled by different processes. • Assimilation of enclosing country rocks is an important process in ACIC evolution. • The xenoliths preserved two main ages related to ACIC and AWCO evolution. [ABSTRACT FROM AUTHOR]

Fossils from natural tanks can contribute to the paleoenvironmental interpretation of the Brazilian Intertropical Region (BIR), an important study area for the Quaternary in South America. In this paper we present results of δ13C and δ18O for Eremotherium laurillardi (δ13C = −4.6 ‰, δ18O = 33.0 ‰), Toxodon platensis (δ13C = −3.8 ‰, δ18O = 35.5 ‰), and Notiomastodon platensis (δ13C = −2.9 ‰, δ18O = 31.6 ‰) from Zabelê tank, compared to other localities, suggesting that these taxa had a mixed-feeder diet with a higher consumption of C 4 plants (p i > 60%), living in a transition zone between woodland savannah and open savannah. The Zabelê tank, northeastern Brazil, presents Optically Stimulated Luminescence ages ranging from 41.2 to 30.4 ky (Lujanian Stage/Age; Late Pleistocene). The origin of the fossiliferous layer through debris flow suggests short periods of intense rainfall under drier climatic conditions. Compared to other locations in the BIR, Zabelê documented a drier climate (δ18O = 31.6–33.4 ‰), which preceded the last glacial maximum. These new isotopic data to OSL ages associated with previous data from the BIR contribute to the understanding of the paleoecology and paleoenvironment dynamics of South America. • New δ13C and δ18O for the three most studied taxa from the Quaternary of the BIR. • These taxa had a mixed-feeder diet with higher consumption of C 4 grasses. • These taxa inhabited a transition zone between arboreal to open savanna. [ABSTRACT FROM AUTHOR]

This paper presents sedimentological, stratigraphic, and palynological data from borehole PBAT-15-43, in which a 230 m long continuous core was sampled in the central portion of the Amazonas Basin, where it was possible to define the contact relationship between Paleozoic deposits of the Andirá and Arari Formations (Tapajós Group). The drilling hole is located in the southern portion of the municipality of Autazes (Amazonas State) and was made available by the Potássio do Brasil Company. Six sedimentary facies were identified in the borehole and grouped into two associations, informally referred to as I and II, representing the Andirá (upper part) and Arari (lower part) formations, respectively. Association I was interpreted as a fluvial environment with channel deposits, flood barriers, and crevasses splay. Association II, on the other hand, represents an alluvial fan environment with predominantly gravitational flow deposits. The facies of association II proved to be sterile for palynomorphs, whereas facies I contain a rich palynoflora, including especially the species Lueckisporites virkkiae , Corisaccites alutas , Hamiapollenites andiraensis , H. karooensis , Vittatina costabilis , V. saccata , V. subsaccata , and Tornopollenites toreutos ; secondarily by species of the genera Punctatisporites , Verrucosisporites , Limitisporites , Cycadopites and Stratopodocarpites , which are considered as belonging to the Permian age. The fact that no marine palynomorphs were detected supports the present interpretations regarding the age and the depositional environments previously predicted for these formations as predominantly fluvial deposits. • Sedimentological, stratigraphic, and palynological data from the central portion of the Amazonas Basin-Tapajós Group. • Six sedimentary facies were identified and grouped into two associations. • Arari Formation - Association I represent a fluvial environment with channel deposits, flood barriers, and crevasses splay. • Andirá Formation - Association II represents an alluvial fan environment with predominantly gravitational flow deposits. • Identification of the Tornopollenites toreutos palynozone Upper Permian in age. [ABSTRACT FROM AUTHOR]

The Salares Norte (SN) Au–Ag belt is here defined as an Upper Miocene-Pliocene metallogenic area, extending for nearly 200 km, located NE of the northern end of the Upper Oligocene-Lower Miocene Maricunga Belt in the central Andes of northern Chile. The belt is located just east of the main reverse NS fault systems which are part of the Sierra Castillo, Potrerillos Mine and Claudio Gay Cordillera faults, limited to the north and south by the NW-striking oblique to the arc Imilac and Wheelwright-Incahuasi regional faults systems. The epithermal deposits within the SN belt are intimately associated with the occurrence of Middle Miocene volcaniclastic basins and Middle to Upper Miocene phreatomagmatic vents and their related high-sulfidation hydrothermal systems. The volcanostratigraphy of the SN epithermal belt comprises volcaniclastic sequences, subvolcanic and volcanic rocks ranging between the Lower Miocene and the Pliocene. High-angle NS reverse faults involving Paleozoic and lower Cenozoic units form the western-southwestern limit of the belt. Folded and faulted Middle Miocene volcaniclastic and volcanic sequences form the main host rock of at least 4 phreatomagmatic events that generated maar-diatreme fields and discrete maar vents, with their related subvolcanic facies, within the widespread Upper Cenozoic volcanic arc, ranging in age between ca. 15 and ca. 4 Ma. These four phreatomagmatic events are spatially and temporarily associated to 4 main high-sulfidation hydrothermal events which have altered both the phreatomagmatic rocks and the Cenozoic country rock of the explosive activity. These hydrothermal systems have formed dozens of discrete hydrothermally altered areas where argillic, advance argillic, silicification and steam-heated alteration are common. Most of the maar fields and the hydrothermal alteration systems are emplaced within a strike-slip tectonic regime with NE-trending shortening which is accommodated in the NW-striking sinistral-normal faults and NE-striking extension structures. These fault systems crosscutting interaction favor the hydrothermal fluid circulation and migration, as well as mineral precipitation on structural and/or primary lithological traps and on NE-striking tension cracks. In summary, the SN epithermal belt is an almost 200 km long and 60 km wide area, mainly NNE-oriented, where epithermal deposits have formed during the Upper Miocene and Pliocene (ca. 13-4 Ma), emplaced within Middle to Upper Miocene volcanic and volcaniclastic sequences associated to small volcanotectonic basins oriented in NS, NE-SW and NW-SE directions, in which most of the high-sulfidation systems are associated to discrete or repetitive structurally-controlled Upper Miocene-Pliocene phreatomagmatic vents and maar fields. • This paper defines a new Au–Ag epithermal belt in the Central Andes of northern Chile. • Novel results in terms of age, volcanic stratigraphyand hydrothermal alteration. • The relationships between Upper Cenozoic HS epithermal areas, local tectonics and phreatomagmatic volcanism are discussed. [ABSTRACT FROM AUTHOR]

The La Rinconada Terrane comprises the core of Margarita Island, Venezuela; it is a composite unit composed of rocks of both continental and oceanic affinity that were brought together and metamorphosed at high-pressure and low- to medium-temperature conditions in a collision zone along NW South America in Albian to Cenomanian time. Details of the ensuing three-stage exhumation path and concomitant eastward translation until Miocene oblique collision of Margarita with central and eastern Venezuela have remained the subject of discussion. In this paper we integrate the results of published age dating and the details of extensive Rb-Sr, K-Ar, 40Ar/39Ar and fission track dating that have been only superficially presented to date. Initial exhumation from high-pressure conditions into ductile mid-crustal levels occurred at 90-80 Ma, followed by essentially isobaric, isothermal conditions for ca. 30 Myr during which the La Rinconada Terrane was subjected to continual ductile penetrative shearing and recrystallization. Partial to total recrystallization with concomitant partial to total isotopic re-equilibration, especially of quartz-rich rocks, was widespread during this time interval. The youngest Rb-Sr, K-Ar and 40Ar/39Ar ages cluster at ca. 50 Ma. Zircon fission track ages of 50–40 Ma corroborate exhumation into brittle levels of the crust at this time. An apatite fission track age of 23 Ma indicates the attainment of shallow depths in Miocene time. This discontinuous history of exhumation fits tectonic models of the Caribbean well. As the Caribbean Plate led by the Antilles Arc entered the gap between the Americas, strongly dextral, transpressive subduction in the SE Caribbean drove shear deep within the forearc. The La Rinconada Terrane of Margarita was exhumed to mid-crustal depths in the Late Cretaceous and is suggested to have occupied high-angle forearc shear zones above the primary Benioff Plane. As the arc migrated past the Guajira promontory and became extensional due to roll-back of Proto-Caribbean oceanic crust north of the Falcón re-entrant of the South American margin, the La Rinconada Terrane formed the footwall of an Eocene lithospheric rift that opened by late Eocene into the Grenada (oceanic intra-arc) Basin, effecting exhumation into the brittle crust. The progressive obduction of the SE Caribbean Plate onto the South American continental margin during prolonged dextral oblique collision completed most of Margarita's exhumation history by middle Miocene time (17–12 Ma). [Display omitted] • High-pressure rocks of Margarita show a discontinuous 70 Myr exhumation path. • Rb-Sr, K-Ar, 40Ar/39Ar, zircon/apatite fission-track data allow sequential tracking. • A 20–30 Myr mid-crustal hiatus is marked by strong ductile penetrative shearing. • Shearing causes partial/total isotopic resetting/recrystallization of many rocks. • Exhumation path correlates well with Caribbean tectonic history. [ABSTRACT FROM AUTHOR]

This work presents facies analysis of pyroclastic and effusive deposits present in areas of the Fernando de Noronha Archipelago (FNA), South Atlantic Ocean. A detailed stratigraphic study was carried out for the Remédios Formation at the Caieira beach and the Quixaba Formation at the Capim-Açu Edge, Americano, and Bode beaches. The lithofacies association for the deposits of the Remédios Formation characterizes non-welded ignimbrites of phonolitic composition generated by concentrated ground-hugging density currents originated from collapses of a buoyant eruption column. Possibly, this phase was followed by a caldera collapse and the exposition of a complex system of dikes at Caieira Beach. For the deposits of the Quixaba Formation, the lithofacies association characterizes scoria and ash flow/grain avalanching deposits, proximal fallout deposits, and Pahoehoe lava flows. The Quixaba volcanism shows evidence of pulses of Strombolian and possibly Violent Strombolian activity alternated with effusive Hawaiian activity. A later stage of magma-water interaction during the Quixaba volcanism led to the formation of a sustained eruption column and fallout deposits with ash aggregates formed through wet aggregation. This paper is the first ever written about aspects of the Physical volcanology of the Fernando de Noronha Archipelago, Brazil. It contributes to the understanding of the evolution of the volcanism that occurred in the Archipelago between ∼12 and ∼1.2 Ma, and of the South Atlantic Ocean. The conclusions of our study are: The stratigraphic study of specific areas of the Archipelago through field observations complemented with laboratory-based pyroclastic and lava flow descriptions allowed us to propose the following evolutionary model: • Explosive magmatic eruptions formed buoyant eruption columns that collapsed and originated ground-hugging concentrated density currents represented by the lithic-rich non-welded ignimbrites. • Volcanic and subvolcanic manifestations generated domes of phonolitic and trachytic composition; i) and ii) might be concurrent. Possibly this phase was followed by a caldera collapse with the exposition of a complex system of dikes at Caieira Beach. • A hiatus in the geological record of about 3 Ma, characterized as a period of quiescence and erosion. • Effusive Hawaiian eruptions with the emplacement of olivine nephelinitic pahoehoe lava flows. Alternated to the effusive eruptions, Strombolian and possibly Violent Strombolian pulses led to mass ejections of juvenile ash, lapilli, bombs, and cognate lithic fragments, forming grain-avalanching scoria deposits, and scoria-and-ash flow deposits. • Stage of dominant water-magma interaction and the formation of a water-rich volcanic cloud, which led to the formation of planar-stratified bedforms, fall-dominated with mixed deposition of ash aggregates in the shape of massive ash pellets, layered and complexly layered accretionary ash pellets, armored and complexly layered armored ash pellets, formed through wet aggregation. [ABSTRACT FROM AUTHOR]

This work presents a comment on the paper "Spatio-temporal analysis of shoreline changes and future forecast using remote sensing, GIS and Kalman filter model: A case study of Rio de Janeiro, Brazil". Results obtained by Palanisamy et al. (2023) differ from other works on the coastline of Rio de Janeiro. Images from the Landsat 1–3 Multispectral Scanner (MSS) satellite and Landsat 5–9 images were inappropriately used in the detailing to delimit the shoreline variations. The lack of information about tides and waves at the time of image acquisition compromised the research results. Oceanographic - meteorological data relating to the month, day and time of the satellite's passage are fundamental in studies of this nature. These forcings are capable of temporarily modifying the morphology and position of coastline. The article proposed by Palanisamy et al. (2023) underestimated the rates of accretion and coastal erosion along the coastline of Rio de Janeiro city by neglecting the issues addressed here. • Results obtained by Palanisamy et al. (2023)on the shoreline variations in Rio de Janeiro city are questioned here. • Methodological procedures used to delimit the historical shoreline variations of Rio de Janeiro city presented inconsistencies. • Results obtained by Palanisamy et al. (2023) on the shoreline of Rio de Janeiro city are incompatibles with other work carried out in the study area. • Comments presented here aim to contribute to the evolution of knowledge about the coastal erosion process (geological hazard) on the shoreline of Rio de Janeiro - Brazil. [ABSTRACT FROM AUTHOR]

The structure and nature of the crust underlying the Northeast Brazilian margins have been investigated based on the interpretation of 12 wide-angle seismic profiles acquired during the SALSA (Sergipe ALagoas Seismic Acquisition) experiment in 2014. In this study, we present the coincident analyses of 2 marine seismic reflection and refraction data, SL07 and SL 08, that have been acquired using 15 and 13 ocean-bottom-seismometers along each profile, offshore the Jacuipe Basin. The SL07 has a 270-km long inland continuation with 46 land-seismic-stations crossing the South Tucano and Reconcavo Basins. Wide-angle seismic forward modellings reveal a narrow necking zone, an intermediate domain with anomalously high crustal velocities interpreted as intruded lower continental crust, and a sharp continent to ocean transition zone, greatly different from the adjacent segments (see companion paper of Evain et al., 2023). Below the Tucano half-grabens, the Moho shows no rise, displaying a flat reflector throughout the landward part of the profile. The high seismic velocities areas in the lower continental crust are interpreted as intrusions that provide an overloading allowing the necessary subsidence for the deposition of the thick sedimentary sequences. Together with the recent information obtained by the analysis of continental basins and aborted rifts, and similar wide-angle experiments on other margins and geodynamic contexts, we propose new paradigm for the thinning process which confirms the crucial role of the lower continental crust and its relation with the upper mantle. We postulate a phase of overloading of the lower continental crust, an exhumation phase of the lower continental crust, and a phase of proto-oceanic crust which involved the lower continental crust and the upper mantle, before the emplacement of a more typical oceanic crust. • This study is part of the SALSA project (S ergipe AL agoas S eismic A cquisition), led by IFREMER (France) and Petrobras (Brazil). • This article focuses on two E-W profiles offshore the Jacuipe Basin, crossing onland the South Tucano and Reconcavo Basin. • Below Tucano half-grabbens, the moho shows no rise, displaying a flat reflector throughout the landward part of the profile. • Offshore, a strong E-W-segmentation is described with a very abrupt thinning and a sharp continent ocean-boundary, greatly different from the adjacent segments • The intermediate domain has anomalously high crustal velocities ans is interpreted as intruded lower continental crust. • The lower continental crust and its interactions with the mantle play a crucial role, giving rise to a new paradigm. • 3 phases implying the lower continental crust are described : overloading and subsidence, exhumation, proto-oceanic crust. [ABSTRACT FROM AUTHOR]

An approach involving data on wave-induced sediment transport estimates is essential for managing coastal environments. Numerical models are powerful tools to understand and investigate many processes responsible for longshore sediment transport (LST) in a systematic way, since direct measurement of LST is a difficult task. This paper presents estimates of longshore sediment transport through numerical modeling of wave-induced sediment dispersion patterns in the Formosa Bay, State of Rio de Janeiro - Southeast Brazil. The analysis was conducted using the computational package Coastal Modeling System/SMC-Brazil and mathematical formulations proposed by Cerc (1984). The results suggest average residual solid discharge (Qsr avg) in the order of 131,442.745 m3/yr in northern sector, −151,908.32 m3/yr in central sector, and 71,987.69 m3/yr in southern sector of investigated area. In addition, it is important to highlight that minor variations in the wave incidence angle may cause changes in the longshore sediment drift, promoting the convergence and divergence zones throughout the investigated area. The results presented contribute to the advancement of knowledge on the topic addressed here and will be useful in future engineering projects related to beach nourishment and the management of coastal areas subject to erosion processes. • Data are presented on simulations of wave-induced longshore sediment transport rates in Baia Formosa Bay, southeastern Brazil. • The Coastal Modeling System SMC/Brazil were used. • Results suggest different solid outflow rates for each sector of investigated area. • The model may provide a basis for planning actions and environmental management in coastal zones. [ABSTRACT FROM AUTHOR]

The Porteirinha Block (PB) provides an important record of the origin and evolution of South American crust. The PB records the generation of Paleoarchean TTG, Mesoarchean anatexis, and Paleoproterozoic crustal reworking. It is exposed as a basement inlier in the Araçuaí Orogen as a result of a tectonic involvement of the continental margins of São Francisco Congo Paleocontinent (PSFC) during the collisional processes of Gondwana amalgamation at the Neoproterozoic. The PB basement unit is the Porteirinha Complex (PC), which consists of TTG orthogneisses, migmatites, amphibolites, metaultramafics rocks and Neoarchean granitoids. In this paper, we discuss the evolution of the TTG orthogneisses and migmatites from PC based on field, geochronological and whole-rock geochemistry data. Zircon U–Pb ages (LA-ICP-MS) show a complex and polycyclic evolution of these rocks. Concordant ages were obtained for crystallization of TTG magma at ca. 3.4 Ga and the geochemical signature supports the idea of TTG generation by partial melting of hydrated mafic crust under garnet-amphibolite facies conditions. Zircon U–Pb ages also suggest crustal reworking events at 3.1 Ga. Metatexite and diatexite domains related to partial melting of TTG orthogneisses are individualized. The migmatites record processes of crustal anatexis and melt generation that occurred between 2.8 and 2.9 Ga (LA-ICP-MS, U–Pb in zircon) and are linked to crustal reworking and heat generation events recognized regionally. The new data presented in this work allow us to establish correlations between Archean and Paleoproterozoic units of the PB and those that occur regionally, particularly those related to Gavião block, where a series of stages and events of early crustal evolution are shared. • Archean crustal evolution of TTG orthogneisses from the São Francisco Congo Paleocontinent. • Zircon U–Pb geochronology shows igneous ages of 3.4 Ga for the precursor TTG magma of the Porteirinha Complex orthogneisses. • The orthogneisses show a typical TTG signature and were generated by partial melt of thickened lower crust. • Meso-Neoarchean crustal anatexis are recorded in metatexites and diatexites domains. • Successive stages of magmatism and crustal reworking have been identified since the Paleoarchean. [ABSTRACT FROM AUTHOR]

This paper presents the geomorphological features of four areas of subtropical, southernmost Brazil displaying striking landforms developed upon Precambrian Camaquã Basin conglomerates in the southern Brazilian shield areas. The distinctive and unique features of the Serra do Segredo cuesta, the Rincão do Inferno canyon, the Casa de Pedra inselberg, and the Pedra da Cruz cap-shaped hills are important examples of such conglomerate geomorphology in South America and in Brazil, where few occurrences were available so far. They are the first documented conglomerate landforms in southernmost Brazil, widening the distribution of such terrains in South America and in the subtropical, southern hemisphere areas, considering recent global reviews. Besides the high scientific relevance for geomorphology as a whole, such features are important also for (1) evidencing the decisive role of lithology, structure, and water flows in the formation of such landforms; as well as (2) ecology and tourism, being distributed within and in the vicinity of the Caçapava UNESCO Global Geopark of southernmost Brazil. • Novel description of conglomerate geomorphology developed upon Ediacaran alluvial/fluvial deposits of the Camaquã Basin in subtropical, southernmost Brazil. • Different landforms developed according to bed tilting and arrangement, as well as to tectonic structures "pre-design". • Decisive role of lithology and water in shaping ranges and hills. • Contribution to a global distribution of conglomerate landforms, especially in humid, subtropical areas. • Geological heritage potential, features within and in the surroundings of the Caçapava UNESCO Global Geopark. [ABSTRACT FROM AUTHOR]

Reservoir characterization is extremely important for understanding and determining the behavior of hydrocarbon reservoirs. The geophysical well logging, widely applied in the oil industry, helps to obtain essential physical properties (acoustic, electrical, mechanical, radioactive and thermal) by deploying measurement devices in the drilled well. This project aims to carry out the geological characterization of hydrocarbon reservoirs in the Amazonas Basin through the analysis of well geophysical logs. Despite the oil-producing potential of the basin, there are few published papers that use geophysical well logging for reservoir characterization. For this study, composite log data publicly provided by ANP were used. Six exploratory wells drilled in AM-T-84 and AM-T-85 exploratory blocks in the Amazonas Basin were selected. By analyzing the geophysical logs of gamma ray, resistivity, density and neutron from these wells, it was possible to identify the hydrocarbon reservoir interval within the Monte Alegre formation and obtain estimates of thickness, shale volume and porosity. The identified reservoir is relatively thin, with an average thickness of 16 m. The obtained shale volume values were relatively high, due to the influence of shale layers present in the Monte Alegre formation. The effect of clay content affected the interpretation process of the well logs; however, it did not significantly impact the reservoir porosity estimation, which ranged between 10.4 and 23.4 %. • The analysis and interpretation of well logs can provide petrophysics properties of the petroleum reservoir. • The Amazonas Basin is one of the pioneering areas for hydrocarbon exploration in northern Brazil. • Despite the clay content present in the formation, relatively good porosity values were obtained for the reservoir. • The temperature values obtained range from 70 to 95 °C. They are contained in the oil generation range (65–165 °C). [ABSTRACT FROM AUTHOR]

The hard rock aquifer systems of Crystalline Aquifer System II (CBASII) and Crystalline Aquifer System III (CBASIII) in Rio Grande do Sul (RS) State, Brazil, were characterized qualitatively and quantitatively through remote sensing, gis-analysis, aeromagnetometry and structural geology analysis. The methods were applied to understand the relationship between the structures and the well capacities in both aquifer systems. Analysis of 139 structures provided a basis for a conceptual model for municipality of São Lourenço do Sul, in Rio Grande do Sul Coastal Plain, scaling systematic and a connection to preexisting structures. Python programming language script are used for statistical analysis can be download to reproduce statistical analysis of this paper with structural data bank. São Lourenço do Sul, is underlain by Pelotas Batholith, a geological complex affected by deformational events related to the Dom Feliciano orogeny. The models provided NW-SE extensions fractures with higher densities in depth for CBASII and CBASIII. Nevertheless, only CBASII is productive due to interconnectivity with preexisting structures WNW-ESE and generated by D 1 and D 2 deformational events of the Pelotas Batholith. CBASIII decreases its permeability as it was affected by the youngest brittle D 3 event an extensional/strike-slip tectonic regime. The regional structures mapping with remote sensing and aeromagnetic ENE-WSE are mostly present in CBASIII. Structures mapping in remote are the same but vary in density. The relationship between oriented magnetic gradients and productive wells suggests fault zones with low hydraulic conductivity in areas with higher anomalies values. Fault damage zones are identified around these anomalies and characterized as the best areas for drilling. [ABSTRACT FROM AUTHOR]

Highlands form one of the essential links ensuring the good performance of the hydrological cycle on Earth, and significant amounts of good-quality water are concentrated in these areas and distributed to lowlands. These resources are indispensable for arid/semi-arid regions such as NE Mexico, where water is scarce and sometimes lacks good quality. In the state of Coahuila, the Serranía del Burro is one of the most important hydrogeological systems, and at least seven aquifers show some type of relationship with this system or benefit from its recharging. In this paper, data from 50 well and spring samples are presented with the goal of identifying the effect of the range on the chemical composition of the surrounding aquifers and the mechanism of recharging. The results show that in this area, the waters are mostly of the type Ca2+-Mg2+-HCO 3 -, with minor contributions from more saline and mixed waters. The main processes responsible for the chemistry of the waters are water-rock interactions, mixing and, cationic exchange, in which, the weathering of silicates and, the dissolution of carbonates through karst processes predominates. Recharging is characterized as fresh and deep, due to the influence of karst and tectonic phenomena throughout the geology of the Serranía del Burro and the adjacent areas. Limited shallow meteoric percolation occurs in the NO of the Serranía del Burro due to the presence of conglomerates and caliche sequences, resulting in low permeability. This study highlights the need to take care of good-quality water resources located in the mountains; adequate exploration work must be carried out in these areas, since waters of questionable quality prevail throughout the state, mainly due to natural salinization processes in lowland areas. • The karstic mountain systems in NE Mexico play an important role in maintaining good quality water resources in arid/semi-arid climate conditions. • Ca2+-Mg2+-HCO 3 - waters are dominant in the Serrania del Burro ranges and surrounding aquifers. • The occurrence of local storms, effective recharge and active tectonism allows infiltration processes over the mountains to be efficient. [ABSTRACT FROM AUTHOR]

This paper describes the lithological and micropaleontological characteristics of a new record corresponding to the last interglacial for Buenos Aires province. Foraminifera were analyzed from an artificial outcrop 4 m thick (36°34′0.97″ S and 57°22′54.43″ W), from the quarry situated in the town of General Conesa, Buenos Aires province at an approximate elevation of 4 m a.s.l. Benthic foraminifera fauna was constituted by a predominance of calcareous forms represented mostly by the species Buccella peruviana and Ammonia parkinsoniana. The micropaleontological and lithological characteristics of all the sedimentary units involved in this locality suggest deposits associated with a transition from a low-energy shallow intertidal or subtidal zone to a higher-energy beach or supratidal environment. Although, the topographic height does not enable conclusive assignment of the age of this coastal deposit (>79.500 kyr), the environmental conditions could be correlated with the penultimate transgressive event that occurred at the beginning of the Late Pleistocene (MIS 5), which would have occurred in a shallow environment with changes in the marine influence. These findings provide new information that contributes to better understanding of the paleoenvironmental evolution of this region where two marine transgressions and two wind deposits have been recognized. • Paleoenvironmental changes during the Late Pleistocene from General Conesa Site, Argentina. • Transgressive event from the beginning of the Late Pleistocene (MIS 5), South America. • Fossil Foraminifera from Buenos Aires province and their paleoenvirnmental implications. [ABSTRACT FROM AUTHOR]

The Magallanes-Austral Foreland Basin preserves an important record of orogenesis and landscape evolution in the Patagonian Andes of Chile and Argentina. This paper evaluates the comparison between the thick Paleogene sequences in the Chilean Peninsula Brunswick (Chorrillo Chico and Agua Fresca formations) and the reduced Paleogene sequence (La Barca Formation) in the Punta Ainol locality, Argentina, by taking account of palynological and geochemical analyses. Warm and humid subtropical conditions (Subtropical Gondwanic Paleoflora) are inferred for the late Paleocene-Eocene interval studied. A new record of Lactoridaceae in the La Barca Formation expanded the known fossil range of this family in Patagonia. During the late Paleocene the Chorrillo Chico and La Barca formations would have been deposited mainly from hyperpycnal flows and this accumulation process continued until the Lutenian in the La Barca Formation. A relative rise in the sea level in the early Eocene would be recognized in both sections. In the middle Eocene a relative fall in the sea level would have occurred with increased terrigenous influx. The rate of sedimentation was similar in both sections during the Thanetian and Ypresian intervals according to the ages assigned by biostratigraphy, suggesting that the sedimentation rate would have been controlled mainly by relative changes in sea level during the Paleocene-Eocene transition. Paleoenvironmental changes during the Paleocene-Eocene transition were characterized at the La Barca Formation of the Punta Ainol section, considering the new geochemical and palynological data provided in this contribution. • A new register of early Paleogene flora of Patagonia. • Paleogeographic changes based on palynological and geochemical data. • New geochemical inferences of the Paleocene-Eocene transition in South America. • A new Paleocene-Eocene record from Southern Hemisphere. [ABSTRACT FROM AUTHOR]

The Mosasauridae underwent a major radiation early in the Late Cretaceous, with the subfamilies Plioplatecarpini and Tylosaurini appearing in the Turonian. Here we report an almost complete mosasaur skull assigned to the plioplatecarpine genus Yaguarasaurus. The specimen was discovered southwest of Vallecillo in the northeastern Mexico state of Nuevo Leon, about 80 km north of Monterrey, in a laminated limestone layer of the upper member of the Agua Nueva Formation (Upper Turonian - ?Lower Coniacian). The specimen is referred to as a new species, Y. regiomontanus. This is the first report of Yaguarasaurus from Mexico and the most complete of the Americas. At roughly 5 m in length, it is one of the earliest large mosasaurids. Along with Yaguarasaurus columbianus , Russellosaurus coheni , and an unnamed plioplatecarpine from Texas, it documents the rapid diversification and expansion of plioplatecarpines in the marine realm in the Turonian. • The Highlight of the paper is that is a new species of mosasaurus described for Mexico. [ABSTRACT FROM AUTHOR]