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Coastal sandstones have high permoporosity and contain significant hydrocarbon reserves, although they present variable flow heterogeneities. The goal of this paper is to understand the distribution of potential reservoir-flow units in the Rio Bonito Formation (early Permian, Paraná Basin) and to investigate heterogeneities on multiscale. We use stratigraphic, sedimentological, 3D model, and petrological data to evaluate reservoir heterogeneities. System tracts were modeled by sectioning the entire succession into five zones. Eleven facies associations were modeled separately within each zone, using geostatistical analysis and different algorithms. The 3D model was validated by jackknife procedure, and the distribution of facies associations adequately represented both depositional and stratigraphic frameworks. The results are adequate in a curve of accommodation changes similar to previous proposal for the study area. Tidal sand bar facies association presents as elongated (parallel to depositional dip) to sheetlike geobodies according to amalgamation grade, while upper and middle shoreface one is mostly elongated (parallel to depositional strike) to sheetlike. Besides, fluvial channel facies association occurs mainly elongated parallel to depositional dip, forming multilateral and multistory geobodies. Modeled depositional geometries were distinguished along the succession, showing similarities to Rio Bonito Formation outcrops, recent environments, and other deposits around the world, such as estuarine strata from Oriente Basin and shoreface ones from Gulf of Mexico Basin. Using a detailed petrological analysis, eleven reservoir petrofacies were defined and classified into good-, medium-, and low-quality reservoirs or non-reservoirs. Tidal sand bar, upper-middle shoreface, and fluvial channel deposits were categorized as the main reservoir-flow units. This study provides predictive scenarios for heterogeneities in reservoirs and may be applied in petroleum fields. • Permian coastal deposits modeled in 3D present similar sedimentological characteristics to other deposits around the world. • Geometry, magnitude, and connectivity of geobodies from the 3D model were applied to capture reservoir aspects at macroscale. • Reservoir petrofacies improve the prediction of reservoir quality on microscale. • Deposits of tidal sand bars, shoreface, and fluvial channels displayed good features as reservoir rock in multiple scales. [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 coastal sedimentary record of Galicia (NW Spain) is important to study sea-level oscillations during the Late Quaternary. The alluvial deposits preserved in the Ria de Coruña and Ria de Arousa are remnants of fluvial valleys flooded by the sea during the successive Pleistocene and Holocene transgressions. A first chronological study by Optical Stimulated Luminescence (OSL)- revealed a fast-component dominated, but dim OSL signal emitted by quartz from this area. Equivalent dose distributions, as obtained with the Analyst software, yielded large overdispersion values, which were negatively correlated to the potassium concentration in the sediment, thus suggesting the influence of beta dose rate heterogeneities. Nevertheless, for most samples many aliquots were considered in saturation, leading to a palaeodose and age underestimation – regardless of the model choice for age calculation. In this paper, we present new analyses using the open-source R package BayLum, as the so-called saturated aliquots may be incorporated in age calculation. Thus, we test this model performance and more commonly used models in retrieving large doses. Then, we discuss the implications for age calculation for these continental sediments formed during the Late Pleistocene. [ABSTRACT FROM AUTHOR]

This paper investigates, from a geomorphological and hydrogeological point of view, the development of piping-sinkhole phenomena at a retreating fluvial-terrace scarp along the lower Ticino River, near Casottole, northern Italy. Piping forms and features are well documented in the literature as complex soil erosion phenomena, usually associated with clayey or carbonate substrata, or to specific fluvial deposits. Such phenomena appear to have never been mapped in the lower Ticino area, and up to now, no evidence of piping-sinkhole occurrence in terraced alluvial plains strictly associated with terrace scarp erosion processes have been observed and reported in the literature. The geomorphological peculiarities of the area were assessed through field surveys, photographic and drone imaging, photointerpretation, and GIS analysis. Moreover, the riverbed morphological evolution was evaluated since the 1950s, and the hydrogeological conditions were analysed. Finally, a large piping-sinkhole database composed by 35 landforms was assembled in a WebGIS system. The piping-sinkhole phenomena were associated with the presence of perched water tables with flows towards the Ticino River, whose origin can be associated with site conditions, the large up dip network of surface water, and local irrigation practices. The research presented here provides a new contribution to the understanding of sinkhole occurrence and formation in previously unstudied terrace-scarp settings, and new insights for fluvial-terrace scarp modelling. Furthermore, it represents an important knowledge base to inform sustainable and effective measures for environmental management and hydrogeomorphic risk mitigation with reference to terrace scarp erosion and sinkholes. • First description of piping-sinkholes forms and features in the lower Ticino River • Large (up to 50 m) scarp piping-sinkholes straddle the retreating terrace scarp edge. • Decades of observations show direct relationship with river meander migration. • Piping-sinkholes can form suddenly causing important disruption. • The forms are still evolving due to a combination of natural and anthropic factors. [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]

This paper focuses on the study of the floodplain and low terrace deposits of the Middle Sebou Valley, which crosses the south-rif corridor and constitutes the eastern limit of the Saïss Basin. The study includes the identification of facies, the determination of architectural elements, the reconstruction of paleoenvironments, and the proposal of a model for deposit formation. The work is based on detailed sedimentological analysis of the deposits, focusing on lithology, grain size, primary sedimentary structures, and the types of contact between facies. Facies analysis identified 21 facies grouped into three associations corresponding to nine architectural elements whose identification was based on the study of their lateral and vertical profiles. The architectural elements identified include the channel (CH), gravel bars and bedforms (GB), sandy bedforms (SB), downstream accretion (DA), lateral accretion (LA), sediment gravity flows (SG), natural levee (LV), floodplain (FF), and abandoned channels and meanders (FF (CH)). The alluvium is organized into rhythmic and fining-up elementary sequences reflecting its deposition in different fluvial environments: alluvial fan, straight to slightly sinuous and braiding-tending fluvial environment, and meandering fluvial environment. Alluvial deposition is controlled by lithology, climate, and tectonics. Lithology and tectonics controlled the slope, the degree of valley confinement, the accommodation space, and the alluvial fan development. Climate controlled the flow regime, sediment dynamics, and the formation of paleosol and calcrete. • Twenty-one defined facies types grouped into three facies associations. • Facies associations correspond to nine architectural elements. • Lithology, tectonic, and anthropic activity afforded the Middle Sebou River deposits. [ABSTRACT FROM AUTHOR]

This paper presents the results of the investigations that defined the formation of the sedimentary deposits and the chronological sequence of the Foz do Chapecó archaeological area in the Volta Grande of the Upper Uruguay River, Southern Brazil. This research was undertaken to contribute to the definition of the diachronic, sedimentary and stratigraphic context of the archaeological occupations. To achieve these goals a geoarchaeological prospection by land and water was conducted, focusing on the valley bottoms, in the whole Volta Grande area. It comprehended the characterization of surface sedimentary deposits, the exposure and analysis of stratigraphic profiles, and sedimentological analysis. Four superficially exposed deposits were identified: i.e., fluvial conglomerates, fine sediments with sandy texture, clay colluviums and current and recent alluvial deposits. Six interesting points for the opening of stratigraphic profiles were identified, and subsequently resulted in the identification of sedimentary facies associated with river-bed, colluvial and colluvial-alluvial deposits. Three of these points presented a clear sequence of archaeological levels in the stratigraphic context. The results indicated that the local sediments are predominantly composed of a variable mixture of silt and clay, with sands occurring predominantly in an interdigitated form. The stratigraphic structure of the identified layers led to the establishment of 7 sedimentary facies, associated with colluvium (Cm), colluvium-alluvium (Sm) and alluvium and fluvial channels (Sm, Fl, Gms, Gt, Gp, Gh). The radiocarbon dating gives an age between 12.0 and 0.3 cal kBP, indicating that the filling of the local valley occurred during the end of the Pleistocene and throughout the Holocene by means of both fluvial and colluvial systems. Nine distinct archaeological levels, with a clear stratigraphic, chronological, and technological characterization were identified. The pre-ceramic archaeological sequence shows the following chronology: the oldest occupation occurred between 12.0 and 11.0 cal kBP (Cm facies); this was followed by an occupation between 10.5 and 9.5 cal kBP (Cm, Gt, Gp and Gh facies in three archaeological sites with eleven 14C data), then an occupation between 8.7 and 8.5 cal kBP (Cm facies), another between 5.7 and 5.5 cal kBP, one more between 4.8 and 4.6 cal kBP (Cm facies), and the last between 3.4 and 3.3 cal kBP (Cm and Sm facies). The ceramic phase seems to form a single dense component with the anthropogenic soil formation, and was dated between 0.5 and 0.3 cal kBP (Sm facies). These data present a previously unpublished chronostratigraphic sequence that is unique for the context of open-air sites in inner southern Brazil. • This research presents a unique example of a well-documented archaeological settlement in an open-air, multi-component site situated in a riverine setting in inland Southern Brazil. • It marks the first geoarchaeological study in Southern Brazil's subtropical oxidic environments, utilizing an integrated approach that includes sedimentology, stratigraphy, radiocarbon dating, and the spatial distribution of archaeological features. • The study's sedimentary sequence aids in reconstructing the paleo-environments of the Upper Uruguay River region. • The findings suggest that prehistoric cultural dynamics throughout the Holocene in Southern Brazil were more complex than previously understood. [ABSTRACT FROM AUTHOR]

Seepage is a common phenomenon in earthfill dams, and one that typically warrants episodic assessment and monitoring by regulatory agencies. Geophysical surveys provide a convenient, cost-effective, and convenient means for assessing seepage, but only if they are applied in effective combinations and if the data are analyzed properly. In the present study, a self-potential survey of streaming potential and a 2D electrical resistivity tomography survey were notably successful in detecting seepage under the embankment of the nearly 90-year-old Standing Rock Dam No. 1 in South Dakota, USA. Self-potential (SP) measurements show a localized negative anomaly of up to 27 mV on the upstream side of the dam, which we interpret to be the inlet or recharge zone for seepage, and a positive anomaly of up to 20 mV on the downstream side, which we interpret to be the outlet or discharge zone. The spatial correlation between our resistivity models, SP data, and topography was excellent. Water-saturated, conductive deposits in the dam's embankment match a negative SP amplitude in the inlet or recharge area. Similarly, water-saturated electrically conductive sediments are characterized by a positive SP amplitude in the discharge area where surface seepage occurs in a topographic low. Six years of water-level measurements in the existing piezometers interpreted relative to the properties and spatial distribution of coarser-grained alluvium (sand and gravel) underneath the dam's embankment fill, suggest that most seepage occurs under the dam. Our approach to assessing seepage in this project should be widely applicable to earthfill dams worldwide, and our modeled results constitute a valuable case study. • This paper is an integrated geophysical and geotechnical investigation of water seepage through earthfill dam. • We used 2D resistivity and Self-Potential methods to discover the seepage zone. • The geotechnical data explained the main reason for seepage under the dam. • The streaming potential created by water flow is a key to detecting the seepage zone. [ABSTRACT FROM AUTHOR]

• Geomorphology of the Paghman and Chaman faults were described based on fieldwork and satellite data. • A reverse fault was mapped west of and almost parallel to the left-lateral Paghman fault. • Based on field observation, the approximate length of surface rupture due to 1505 earthquake is ∼30 km. • The Paghman and Chaman faults could produce an earthquake of Mw 7.3–7.8 in the Kabul Basin. The city of Kabul, Afghanistan, lies within the Kabul Block, which is bounded by the Sarobi, Gardez and Paghman fault, the northern extension of the Chaman fault, accommodating oblique convergence between the Indian and Eurasian plates. In this paper, we describe the geologic structure and tectonic geomorphology of the northeast-striking Paghman fault and a ∼10-km-long portion of the Chaman fault using a combination of field observations and remote sensing data, and assess evidence for rupturing in the 1505 historical earthquake. The Paghman fault is predominantly a left-lateral strike-slip fault with a minor dip-slip component along the eastern margin of the Paghman Mountains. The Chaman and Paghman faults displaces Paleogene to Quaternary units with clear displacement of recent deposits. Continuous left-lateral movement of the both faults have caused stream deflection, capturing, abandonment, and finally, incision of alluvial deposits inside the Kabul Basin. We identify several stages in the alluvial fan development and displacement that were once a continuous unit displaced left-laterally as a single fan but are now incised by beheaded and offset stream channels. An approximately 30-km-long active fault trace is identified with geomorphic evidence of recent faulting and vertical offset ∼0.5–3 m, which we interpret is related to the historical 1505 earthquake in the area along the Chaman and Paghman faults. Our observations indicate significant along-strike variations in faults trace geometry. The seismic event comprises several fault segments separated by discontinuities such as stepovers. The two faults have accumulated enough elastic strain to cause a larger earthquake since the 1505 quake. [ABSTRACT FROM AUTHOR]