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During the Permian, the northwestern portion of the supercontinent Gondwana experienced significant climate changes, among which the increasing aridity in the Parnaíba Basin, located between Brazil's northern and northeastern regions. The marine influence associated with the Panthalassa Ocean, evident in the Silurian and Devonian deposits, was progressively attenuated in the late Carboniferous, culminating in extensive continental deposits during the Permian and the Early Triassic in this region. In this paper, we present the first palynofacies analysis of the Permian Pedra de Fogo Formation, conducted concurrently with the description and association of sedimentary facies from outcrops located in the state of Maranhão, southwest of the Parnaíba Basin. A total of 15 m of sedimentary succession was described, and 28 samples were selected for palynofacies analysis. As a result, we identified six sedimentary facies, which were grouped into two distinct facies associations: Fa1 – Central Lake and Fa2 – Playa Lake. The palynofacies analysis considered the sedimentary organic matter, classifying it into amorphous organic matter, phytoclasts (subdivided into eight subgroups), and palynomorphs (with six subgroups). Integrating the results enabled an understanding of the depositional context, which is closely related to water dynamics and climate seasonality. The shallow lake system interpreted during the wet phases recorded interruptions in the normal sedimentation of the central lake due to turbidite deposits associated with ephemeral rivers. Conversely, during dry phases, salt precipitation occurred with subsequent substitution and aerial exposure of the surface when the water balance was negative. Eodiagenetic events were inferred and are considered throughout the article. The alternation of the hydrological regime allowed the deposition in proximal, transitional, and distal environments, creating a distinctive mosaic of wetland landscapes. The data presented indicate humid conditions within a context of increasing aridity in the studied location, particularly in the upper part of the Pedra de Fogo Formation. • First palynofacies analysis of the Permian Pedra de Fogo Formation, Parnaíba Basin. • New data of facies association for the upper part of Pedra de Fogo Formation. • A wetland in the Cisuralian of Western Gondwana. [ABSTRACT FROM AUTHOR]

Climate change has increased the frequency of extreme weather events and, consequently, the number of occurrences of natural disasters. In Brazil, among these disasters, floods, flash floods, and landslides account for the highest number of deaths, the latter being the most lethal. Bearing in mind the importance of monitoring areas susceptible to disasters, the REMADEN/REDEGEO project of the National Center for Monitoring and Natural Disaster Alerts (Cemaden) has promoted the installation of a network of soil moisture sensors in regions with a long history of landslides. This network was used in the present paper as a base to develop a system for moisture forecasting in those critical zones. The time series of rainfall and moisture were used in an inversion algorithm to obtain the geotechnical parameters of the soil. Then the geotechnical model was used in a forward calculation with the rainfall prediction to obtain the soil moisture forecast. The landslide events of March 2020 and May 2022 in Guarujá and Recife, respectively, were used as study cases for the developed system. The obtained results indicate that the proposed methodology has the potential to be used as an important tool in the decision-making process for issuing landslide alerts. • This paper presents a novel system aimed at predicting soil moisture conditions based on rainfall forecast data. [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]

Centroid moment tensor (CMT) determination in intraplate regions like Brazil can be very difficult, because earthquakes are often recorded just at few and distant stations. This paper introduces a methodology for datasets like that. The methodology is based on waveform inversion in which each source-station path has its own velocity model. The 1-D path-specific velocity models are derived from the Rayleigh- and Love-wave dispersion curves. The waveform inversion is accompanied by posterior check of numerous P-wave first-motion polarities. An important innovation is the use of so-called frequency range test. The test basically consists in calculating CMT's for many different frequency ranges to assess the stability and uncertainty of the solution. The method is validated on two Brazilian earthquakes and a well-known Greek event. An offshore event (mb 5.2) in SE Brazil is inverted with four stations, at epicentral distances 300–400 km. The other Brazilian earthquake (mb 4.8 in Central Brazil) is even more challenging – only two broadband stations at 800–1300 km are at disposal for waveform inversion. The paper unambiguously demonstrates that the path-specific velocity models significantly increase the reliability of the CMT's. While standard models (e.g. IASP91) typically allow waveform modeling up to epicentral distances of the order of a few (∼10) minimum shear wavelengths (MSW), using the path-specific velocity models we successfully inverted waveforms up to > 20 MSW. Single-station waveform inversions are thoroughly tested, but multi-station joint inversions are shown to be preferable. The new methodology of this paper, providing a reasonable estimate of focal mechanisms and their uncertainties in case of highly limited waveform data, may find broad applicability in Brazil and elsewhere. [ABSTRACT FROM AUTHOR]

Focal-mechanism determination of weak events recorded in sparse networks is challenging. First-motion polarities are often available at relatively distant stations, and waveforms only at a few near stations can be modeled. A two-step approach of how to combine such data has been suggested recently (Cyclic Scanning of the Polarity Solutions, or CSPS method; Fojtíková and Zahradník, 2014). It starts with creating a suite of first-motion polarity solutions, which is often highly non-unique. The next step consists of repeating full waveform inversion for all polarity solutions. Even few stations may efficiently reduce the non-uniqueness of the polarity solutions. Centroid depth, time, scalar moment and uncertainty estimate of the well-fitting double-couple solutions are obtained. The CSPS method has been extended in this paper by adding a new feature, i.e. repeated inversions using multiple first-motion polarity sets. The polarity sets are created by projecting the stations on focal sphere in several available velocity models, thus accounting for the takeoff angle uncertainty. The multiple polarity sets provide assessment of the CSPS solution stability. These ideas are demonstrated on a comprehensive analysis of a rare event in central Brazil. It is the Mw ∼4 mainshock of the Mara Rosa 2010 earthquake sequence (Barros et al., 2015, Carvalho et al., 2015). We employ polarities at 11 stations (distances < 730 km) and invert full waveforms at two stations (CAN3 and BDFB at distances ∼120 and 240 km), for 0.1–0.2 and 0.05–0.125 Hz, respectively. Six polarity sets reflect the takeoff angle uncertainty. The obtained CSPS results are very stable across all the polarity sets (in terms of depth, Mw, and strike/dip/rake angles). It is found that the Mara Rosa mainshock mechanism deviated from the composite solution of the whole sequence by 38°. The paper also includes a test simulating situations at which just a single waveform is used, and how it negatively affects the solution stability. [ABSTRACT FROM AUTHOR]

Every year, Brazil grapples with the destructive impact of landslides, typically during the summer season. The National Centre for Monitoring and Alerts of Natural Disasters (Cemaden) places significant emphasis on studying these phenomena to understand their processes and causes more deeply. One key challenge faced in this endeavour is the procurement of geotechnical properties of the soil in high-risk areas, with soil moisture being a crucial factor. Collecting point samples for acquiring these geotechnical parameters is not only costly but also limited in providing a comprehensive two-dimensional or three-dimensional coverage. Therefore, the primary aim of the proposed project is to validate the method of acquiring soil moisture data through geophysical surveys in both 2D and 3D scenarios. Data was gathered from soil moisture stations within Cemaden's network and various collected samples to confirm the results. To generate more controlled yet realistic conditions, a sequence of field infiltration experiments was conducted. The findings, related to the ability of the geoelectric method to define soil moisture, derived from this project form an invaluable foundation for future investigations spearheaded by the Geodynamics Group and its collaborating institutions. • This paper presents a series of experiments to understand the method of acquiring soil moisture through the DC method. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to document the changes observed in the Quaternary dinoflagellate assemblages from 80 core samples from the Campos Basin. The Interglacial (Subzone X1), Glacial (Subzones Y5 to Y2), Last Glacial Maximum (Subzone Y1) and Post-Glacial (Zone Z) intervals were identified. High abundance of Operculodinium centrocarpum suggests the warm, high salinity and nutrient-poor water conditions dominated the upper water column of the Campos Basin. The climate and oceanic current dynamic of the continental slope of the Campos Basin appears to has been a significant controlling factor in the distribution of dinocysts, particularly of O. centrocarpum , during the Pleistocene/Holocene transition. [ABSTRACT FROM AUTHOR]

This paper provides diet interpretations for nine giant ground sloth species that lived in the Brazilian Intertropical Region, through the relative muzzle width technique and occlusal surface area (except Mylodonopsis ibseni). We propose that Eremotherium laurillardi , Ocnotherium giganteum , Mylodonopsis ibseni , Glossotherium phoenesis , Catonyx cuvieri , Valgipes bucklandi , Ahytherium aureum , and Australonyx aquae were adapted to had a mixed-feeder diet, having a great oral food processing, which could indicate an adaptation to need less from the fermentation on digestive tract, and similar, or even higher, metabolic requirements in comparison with ungulates of similar body mass. While, N. maquinense was adapted to a browser diet, and probably presented high fermetantion capability and low metabolic requirement, in comparison with all other giant ground sloth taxa. • The diet of nine extinct giant ground sloths from BIR is presented. • Eight taxa were mixed-feeder, with great oral food capacity. • Eight taxa had high metabolic requirements. • Nothrotherium was browser, with low oral food capacity. • Nothrotherium had low metabolic requirements. [ABSTRACT FROM AUTHOR]

This paper discusses the role of fluvial archives as records of the landscape evolution and geomorphological configuration of the southeastern Brazilian highlands (Brazilian Atlantic Plateau), particularly in the Espinhaço meridional ridge. A cartographic bases search was carried out, complemented by fieldwork to support the definition of the studied 10 valleys. During fieldwork, depositional levels and sequences were described in terms of composition, thickness, organization, and transitions, vertical sections were selected and described. Different fluvial levels in each valley were identified mainly by the heights and characteristics of the sediments of which they were composed. Sediments were sampled at 24 representative points and dated using the Single-Aliquot Regenerative Optically Stimulated Luminescence technique (SAR OSL, five aliquots). The depositional archives allow the reconstruction of six regional relief evolution phases associated with fluvial processes throughout the Late Quaternary (from 26 ka to present). On the upper quartzite surfaces, the bottom valleys are wider, and the channels are straighter, with beds and/or rocky banks than the down surfaces. In this context, the current river dynamics have been controlled by local baseline levels that have reduced the intensity of downcutting. In the lower crystalline areas, valleys tend to be narrower and deeply dissected, favoring the mischaracterization of older archives. Stepped depositional levels in these compartments indicate the role of the Brazilian Shield tectonics (epirogenetic uplifts) in regional geomorphological evolution. Furthermore, the set of deposits and river system characteristics, which show filled valley bottoms, reflect the current stabilization of the regional base level and indicate the importance of lithostructural, climate, and anthropic aspects for understanding the role of fluvial processes in landscape configuration. • The relief evolution in Southern Espinhaço Ridge has been strongly influenced by the lithostructure since the Pleistocene. • The upper quartzite compartment and the Gouveia Depression have been modeled differently by fluvial processes. • Six fluvial phases since 26 ka have been identified in the Gouveia Depression. [ABSTRACT FROM AUTHOR]

During the MAGIC (Margins of brAzil, Ghana, and Ivory Coast) experiment, five combined wide-angle, and reflection seismic profiles were acquired in the Pará-Maranhão/Barreirinhas/Ceará basins northern Brazil. This is a pull-apart passive margin, with two strike-slip borders. The equipment deployed includes 143 sea-bottom seismometers (OBS), a 4.5-km seismic streamer, and a 7587-in3 airgun array. In this paper, we focus on the distal parts of three profiles, and one entire transverse NW-SE profile, located on the presumed Cretaceous oceanic crust. Forward modelling of these wide-angle data sets reveals an E-W lateral evolution of the oceanic crust spreading initiation with: 1) just after the so-called intermediate domain, 60 km-wide domain that consists of a 5-km-thick crystalline crust. The basement presents two layers characterized by high acoustic velocity. This domain is bounded to the NW by a NW-SE volcanic line (Volcano Alignment), and 2) a 5-km-thick oceanic crust consisting of two layers characterized by "normal velocities" spanning between the two main fracture zones that fringe the Pará-Maranhão-Barreirinhas-Ceará segment. Despite a similar thickness, these two sub-domains present different velocity distribution in their two layers. They are both overlain by 5.5 km of sedimentary deposits. Forward wide-angle modelling confirms that the seafloor spreading process was progressive, with firstly the emplacement of a proto-oceanic crust, and then a thin oceanic crust. The "proto-oceanic" crust presents a similar seismic velocity with the intermediate domain interpreted as exhumed lower continental crust except for the lower part where the intruded lower crust gives place to a very sharp Moho at the base of the proto-oceanic domain. By contrast, the thin oceanic crust domain has a lower velocity structure in its upper layer, that is interpreted as basalt and is absent in the proto-oceanic crust. This eastward evolution, as also observed in the Provençal Basin, and the Santos Basin, suggests the involvement of the lower continental crust in the first steps of seafloor spreading. • The Pará-Maranhão-Barreirinhas-Ceará passive margin in the Equatorial Atlantic segment presents a strong E-W-segmentation with: • The transition to oceanic crust takes place in stages, with the presence of proto-oceanic crust before a "more typical" but still thin oceanic crust eastward • This eastward evolution implies lower continental material flow inside a first proto-oceanic crust and some continental mantle lithosphere erosion. [ABSTRACT FROM AUTHOR]

This paper shows the results obtained from a group of simple and basic procedures used to assess slope instability in terms of shallow landslides on data-scarce hillsides at the slope unit scale. The procedures are based on engineering geological mapping to obtain geological and geotechnical data and on an adapted Hovland 3D safety factor (SF 3D) associated with a van Genuchten infiltration model to simulate the rainfall percolation. The procedures were applied on a data-scarce hillside in the Campos do Jordão municipality located in the Mantiqueira Mountains, São Paulo state, Brazil. This area was chosen because it is affected by shallow landslides due to a loss of shear strength when suction decreases or dissipates due to rainfall infiltration. The combined procedures permitted the total SF 3D to be obtained from the partial SF of each grid cell (considering 4 different rainfall events and quasi-saturation conditions) and the failure probability (SF 3D < 1) and marginal probability (1

Synchrotron radiation (SR) is an electromagnetic radiation produced when electrons are forced to assume a curved trajectory resulting in an emission of a bright beam of high energy photons. This phenomenon is carried out in large particle acceleration facilities called synchrotrons, which is equipped with experimental stations at the end of each spot where the beam is emitted. In an applied sense, SR allows the investigation of materials of different nature, from synthetic to biological, from macro to the nano-scale. Since fossils are typified as environmental samples (i.e. a mixture of different type of compounds), SR has become an important approach to modern palaeontology. Due to the selective nature of the fossil record, bias can occur in both, morphology and geochemistry. Therefore, palaeontologists are frequently susceptible to equivocal interpretations. To diminish this problem, the employment of analytical methods became paramount in many areas of palaeontology. However, most benchtop equipments are limited in resolution, they also require particular experimental conditions (e.g. vacuum), and complex sample preparations (e.g. extraction from rocks). In this scenario, SR is advantageous as it allows non-destructive experiments to be performed in situ in qualitative or quantitative modes, in larger areas of the samples, still maintaining high spatial resolution and low detection limits. Nonetheless, in contrast to worldwide palaeontology where SR is widely applied, this analytical approach remains still poorly explored in South America. In Brazil, only a few studies used SR to resolve palaeontological problems. This panorama contrasts with the fact that in Brazil had a 2nd generation synchrotron, the UV and Soft X-Ray Light Source (UVX), which operated for 22 years. Nevertheless, this machine was substituted by a new 4th generation synchrotron, Sirius, which has been in operation since early 2020. Among its 13 beamlines, some will be best suitable to analyse palaeontological material, both through spectroscopy and imaging at a nanoscale. Therefore, it is expected that fossils will be routinely analysed in Sirius, being able to push forward the current knowledge in palaeontology. Here, we review the application of SR to the investigation of fossilization and other challenging topics in palaeontology. In this context, a fossil beetle from the Cretaceous Crato Formation (NE Brazil) was analysed using synchrotron radiation micro-X-Ray fluorescence (SR-μXRF). Results revealed which elements are involved in the process of fossilization and diagenesis, providing additional evidence for the preservational model of insects in this unit. Due to the high resolution and non-destructive properties, the SR-techniques have provided invaluable information on rare and delicate fossils. Considering all these aspects, it is now clear that this analytical approach has a high potential of expanding not only the frontiers of palaeontology, but also of the South American Earth sciences as a whole. • The SR provides invaluable information on rare and delicate fossils. • In Brazil, only a few studies used SR to resolve palaeontological problems. • This paper reviews the application of SR techniques in palaeontology. • A case study is also presented of a fossil beetle from the Cretaceous. • SR can expand the frontiers of palaeontology, especially in South America. [ABSTRACT FROM AUTHOR]

Extensive urbanized areas, characterized by waterproofed soils, increase runoff, which reduces the rainwater infiltration into the ground. However, water, sewer, and rainwater distribution systems leak, as there is excess irrigation in green areas, resulting in anthropic recharging in urban aquifers larger than in rural areas with equivalent climates. This scenario occurs in the Upper Tietê Watershed (UTW), an area of 5,868 km2 that drains the principal rivers of the São Paulo's metropolitan region in Brazil, where groundwater plays a complementary role for domestic, industrial, and agricultural supplies, totalizing extraction rates higher than 11 m3/s. In this paper, a Geographical Information System (GIS) was established to assess regional groundwater availabilities using adaptations of classic recharge methods such as soil water budget calculations and estimation of minimum sustainable river flow. For this, a surface runoff map, based on soil and slope terrain data, was evaluated using the information on water and sanitation infrastructure and meteorological data. We found that recharge in urban areas (with water and sewer mains) was 437 mm/yr and 106–407 mm/yr in rural areas. Considering the need to maintain a minimum historical flow of 20 m3/s in the hydrographic basin of the Tietê River, the total exploitable groundwater is 33 m3/s. The compilation of various GIS methods can help decision-makers develop alternative water security management plans in complex urbanized-regions such as in the metropolis of São Paulo. • A GIS was established to assess regional groundwater availabilities through adapted classical recharge methods. • Recharge in urban areas is associated with natural infiltration, leakages from water distribution mains and sewer systems. • The compilation of various methods in a GIS can help decision-makers to develop alternative water security management. [ABSTRACT FROM AUTHOR]

The new Pleurodira turtle Itapecuruemys amazonensis gen. et sp. nov. from the Itapecuru Formation (Parnaíba Basin, Brazil) is described. The new species is represented only by its holotype, which consists of an almost complete carapace and plastron, with an oval-shaped outline. The most peculiar characters of Itapecuruemys amazonensis are: neural plates six and seven are separated by costal six, and the seventh neural plate contacts the sixth, seventh and eighth costal plates and a suprapygal. The phylogenetic hypothesis proposed in this paper suggests that Itapecuruemys amazonensis , together with Cearachelys and Galianemys spp., form a monophyletic assemblage and also widen the paleoherpetological diversity of the Itapecuru Formation in the Parnaíba Basin (Brazil). • A new species of Pleurodira from theItapecuru Formation (Parnaíba Basin, Lower Cretaceous). • The new pleurodira presents a gap in the neural series and seventh neural bone with seven sides. • Increase in the diversity of Brazilian fossil chelonians. • The new species allows a better understanding of the paleoenvironments and paleobiogeographic distribution of the Aptian Pleurodira. [ABSTRACT FROM AUTHOR]

The fossil record of anurans in South America is scarse, especially for Mesozoic-aged beds. The aim of the present paper is to describe a new neobatrachian anuran coming from the Early Cretaceous (Aptian) Crato Formation from Brazil. The specimen, represented by a nearly complete skeleton is reminiscent to the extant clade Hyloidea. In contrast with recent claims, this finding, together with previously known fossils from South America indicates that modern frog clades were present and well-diversified by 40 million years before the K/T boundary. In the same sense, the analysis of Mesozoic and Paleogene anuran record in South America contradicts the hypothesis of massive anuran extinction at the K/T boundary. • A new neobatrachian anuran coming from the Early Cretaceous (Aptian) Crato Formation from Brazil is described. • Present record constitutes an important addition to the scarse fossils of Mesozoic anurans in South America. • Present finding indicates that modern frog clades were well-diversified by 40 million years before the K/T boundary. • In Patagonia, the K/T boundary does not accounts for a massive anuran extinction. [ABSTRACT FROM AUTHOR]