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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]

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]

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