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Modelling of many real-world processes, such as drug delivery, wastewater treatment, and pharmaceutical production, requires accurate descriptions of the dynamics of hard particles confined in complicated domains. In particular, when modelling sedimentation processes or systems with driven flows, it is important to accurately capture volume exclusion effects. This work applies Dynamic Density Functional Theory to the evolution of a particle density under diffusion, external forces, particle–particle interaction, and volume exclusion. Using a spectral element framework, for the first time it is possible to include all of these effects in dynamic simulations on complex domains. Moreover, this allows one to apply complicated no-flux, and other non-local, non-linear, boundary conditions. The methodology is also extended to control problems, addressing questions of how to enhance production set-up in industrially-motivated processes. In this work the relevant models are introduced, numerical methods are discussed, and several example problems are solved to demonstrate the methods' versatility. It is shown that incorporating volume exclusion is crucial for simulation accuracy and we illustrate that the choice of boundary conditions significantly impacts the dynamics. [ABSTRACT FROM AUTHOR]

Mangrove forests are critical coastal ecosystems that provide great socio‐ecological services, which are also highly vulnerable to climate change, particularly to sea level rise (SLR). Here we assess changes in mangrove forests in four distinct river/tide/wave‐dominant large deltas along the Indo‐Pacific coast based on 1,336 remote sensing images by machine learning techniques. We find that mangroves are migrating seaward at a rate of 18% ± 12% m/yr, which can offset landward mangroves loss, 67% of which caused by land use conversion. The fact that mangroves are expanding seaward with accretion rates exceeding SLR suggests that climate change has not yet triggered substantial loss in deltaic mangrove forests. Assuming that present environmental conditions do not change and that sediment and organic deposition in the deltaic topsets match SLR rates, we project that 90% of deltaic mangrove forests may start to retreat after 132–194 years. Early inundation of mangroves will occur in wave‐dominated delta. Plain Language Summary: Mangrove forests provide significant ecological and societal services, and mitigation global warming. However, large‐scale loss in mangroves could be induced by anthropogenic drivers and sea level rise (SLR). Our study based on deltas along the Indo‐Pacific coast, highlight that mangroves are expanding seaward at a rate of 18% ± 12% m/yr, indicating that there is little impacts from SLR and has not been substantial loss in mangrove forests in these deltas so far. Mangrove expansion here can efficiently offset 67% landward mangrove losses indicates that our new model project that 90% of mangrove shorelines will may start retreating within 132–194 years. We conclude that favoring mangroves expansion seaward would enhance coastal protection and reduce the need of landward mangrove restoration. Key Points: Mangroves along typical deltas are expanding seaward of about 18% ± 12% m/yr, indicating that there is little impacts from sea level riseMangrove expansion here can efficiently offset 67% landward mangrove lossesNew model project that 90% of mangrove fringes may start retreating within 132–194 years, and wave‐dominated delta present early inundation [ABSTRACT FROM AUTHOR]

Notch development at the base of sea cliffs is an important control on cliff recession rates, but a detailed mechanistic understanding of notch formation by swash abrasion is lacking. We conducted physical experiments, using homogeneous erodible rock simulants, to study notch‐forming mechanisms under periodic sediment‐laden bore impacts. Our findings reveal shifts in the temporal dynamics of notch development. Initially, swash uprush and vortex formation contribute to a positive feedback loop that creates a shallow and wide notch. Subsequently, upward erosion ceases, and notch backwear and downwear are dominated by the vortex. Eventually, sediment deposition armors the notch floor; this negative feedback loop reduces erosion. The sediment size determines the amount of erosion, with a range of grain sizes generating maximum erosion. This indicates a dependence on the momentum of the sediment particles entrained within the bore. This research reveals fundamental notch formation mechanisms driven by swash abrasion. Plain Language Summary: When waves attack a rock cliff, they gradually undercut the cliff and remove materials, forming a wave‐cut notch. Studying how notches form and develop in natural settings takes a very long time, so we created a weaker cliff in the laboratory using easily eroded foam. The cliff was exposed to repeated impacts from bores carrying sediment, representing the impact of broken waves. Notch formation is observed over a few hundred hours. Initially, the notch is wide and shallow. As it grows, abrasive sediment cannot be propelled into the roof, stopping the upward expansion of the notch, and sediment piles up at the bottom, blocking further downward erosion. The notch continues to deepen, but at a decreasing rate. The size of the beach sand or gravel has an important influence on the erosion rate. If the sediments are too large or too small, little erosion occurs, whereas sediments of a certain size can cause rapid erosion. This is because waves need to be able to entrain sediment and hurl it with sufficient force against the cliff to cause erosion. Key Points: Controlled laboratory experiments with repeated swash impacts reveal positive and negative feedback mechanisms in abrasion notch formationNotch geometry varies over time and is determined by swash impact location, vortex formation and sediment depositionGrain size modulates beach shape and sediment‐laden bore momentum, collectively influencing notch development [ABSTRACT FROM AUTHOR]

ABSTRACT Present day submarine canyons are active conduits for the transfer of large volumes of sediment, carbon and pollutants from continents to oceans. However, the evolution of submarine canyons over geological timescales remains poorly understood due to their erosional nature and low preservation potential. The Late Cretaceous Punta Baja Formation represents a well‐preserved submarine canyon‐fill that evolved on a tectonically‐active ocean‐facing margin. Exposures provide kilometre‐scale continuous strike and dip sections of the 120 m thick and 1.2 km wide feature. An inherited tectonic fabric influenced the location and orientation of canyon incision into fluvial bedrock. The stratigraphic evolution of the Punta Baja submarine canyon is reconstructed from incision to fill, which shows that it remained an active sediment conduit throughout the time represented by the preserved fill. The depositional architecture of the north–south oriented erosionally confined canyon‐fill is asymmetrical, with sub‐vertically stacked channel‐fills to the west, and an overbank confined by the canyon margin to the east. Sedimentary process interactions led to depositional patterns that are considered distinct to submarine canyon fills. Dynamic topography generated by mass‐wasting processes captured sediment and drove knickpoint development, an autogenic mechanism that modifies sediment delivery to the ocean floor. Widespread upstream dipping surfaces in channel‐fills are interpreted as the stratigraphic expression of upstream migrating supercritical‐flow bedforms, which played an important role in sediment storage and transport in the canyon. The steep relief and internal topography of canyons leads to complicated and characteristic confined overbank flow behaviour and depositional patterns. This study provides insight into how processes that are observed in modern canyons are selectively preserved through the lifetime of the canyon and construct or destroy stratigraphy on geological timescales. [ABSTRACT FROM AUTHOR]

Salt diapirs dominate the structure in many sedimentary basins and control the preservation and migration of hydrocarbon. The formation of salt diapirs generally falls into two endmember models: active (up-building) and passive (down-building) diapirism. In the active model, salt diapirs rise from salt buoyancy to pierce through the sedimentary overburden, whereas in the passive model, salt diapirs result from differential loading of sediments during deposition. These endmember models are mostly conceptual or kinematic, the mechanics of active and passive diapirism and their relative roles and interactions in the formation of salt diapirs remain uncertain. Here, we use two-dimensional high-resolution numerical models to investigate the primary factors and critical conditions for active and passive diapirism. Our results indicate that it is improper to use driving mechanisms to classify salt diapirs, because the buoyancy-driven active salt diapirism involves differential loading, while the passive diapirism requires salt buoyancy. The rise of salt diapirs is more sensitive to the effective viscosity of the overburden than to the salt viscosity. Stiff overburdens could prevent the rise of salt diapirs, but they could be pierced by salt diapirs if plastic yield of the overburden is allowed. During deposition, the coupled salt-sediment deformation, driven by both salt buoyancy and differential loading of sediments, can lead to various diapiric salt structures and minibasins. Regional tectonic stress generally promotes salt diapirism by enhancing strain weakening of salts and overburdens. We suggest that the classification of active and passive salt diapirism is an oversimplification in most cases. We propose a general model of the formation of salt diapirs that usually begins with dome initiation driven by salt buoyancy, followed by syndepositional down-building controlled by sedimentation and differential loading and ends with canopy formation when sedimentation stops. [ABSTRACT FROM AUTHOR]

Utilizing over 31   000 Lg waveforms from 136 crustal earthquakes recorded at 346 regional stations, we conduct detailed tomographic mappings of the Lg Q structure across Eastern Asia in a frequency range from 0.5 to 4.0 Hz. By improving the standard two-station (TS) method, we effectively correct non-unity site response ratios using site responses estimated at individual stations. This innovative approach combines the flexible recording geometry of the TS method with the precision of reversed two-station (RTS) and reversed two-event (RTE) methods, producing a comprehensive data set devoid of source and site effects for Q tomography. To address unsolvable 3-D structural effects in the Lg spectral amplitude modelling, we justify these as modelling errors with a Gaussian distribution. This approach supports our SVD-based tomographic method, allowing for effective inversion of attenuation parameters and quantitative assessment of model resolution and errors. Our results reveal a complex relationship between Lg Q and the tectonic characteristics of Eastern Asia. In well-resolved regions, low Q o (1-Hz Q) values correspond to areas with high heat flow, partial melt, thick sediment and recent tectonic-thermal activities, in contrast to high Q o values in stable, ancient crusts lacking recent tectonic activity. Rift basins are characterized by low Lg Q o, whereas flexural basins generally have high Q o basements. We also note that post-formation factors, such as sedimentation and crustal flow intrusion, significantly impact Q o values. Furthermore, Lg Q shows a complex frequency relationship, though the power-law approximation with positive power η remains useful. The frequency dependence power η is inversely related to Q o: the regions with low Q o typically have high η and vice versa. This study provides reliable attenuation tomographic and relative site response models for Lg waves in Eastern Asia, pertinent for relative geophysical studies. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of shoreline dynamics in the Thanjavur district, focusing on erosion and accretion trends from 1992 to 2022. The coastal region was partitioned based on Taluk boundaries to discern distinct patterns in erosion and accretion. The Peravurani region displayed stability, while the Mettupalayam Coast exhibited modest accretion, influenced by sediment deposition from the Tedakkiar River. Mettupalayam had the highest net shoreline movement (NSM), contrasting with the Mandiripattinam coast’s prevalent erosion trend. Areas such as Ammani Chattram and Setubava Chattram coast remained relatively stable, while Ganeshapuram, Sendalapattinam, and Sembalpattinam coasts experienced low accretion linked to the Ambuliar River. The study found that the maximum erosion in the study area is 4.1 m/yr (end point rate (EPR)) and 4.21 m/yr (linear regression rate (LRR)) at the Maravakkadu coastal region, and the maximum accretion is 3.75 m/yr (EPR) and LRR of 4.12 m/yr at the Mettupalayam coast. Employing the Kalman filter, future shoreline projections for 2032 and 2042 revealed heightened erosion and accretion trends, identifying vulnerable areas and distinct accretion patterns. It has been predicted that the eastern part of the coastal stretch erodes towards the land, and the western part is accreting. The dynamic interaction of erosion and accretion in Sendalapattinam underscored historical influences on future projections. However, ongoing erosion on the Maravakkadu coast may entail potential economic consequences. The findings emphasize the need for informed coastal management strategies, integrating historical data and future predictions. This will help maintain the coastal ecosystem and community resilience in the changing shoreline dynamics. [ABSTRACT FROM AUTHOR]

Water erosion poses a significant threat to the sustainability of natural resources and hydro-agricultural infrastructure, particularly in the Mediterranean region, including Morocco. The Allal El Fassi watershed faced such challenges and underwent anti-erosion measures between 2008 and 2014. This study aims to evaluate the effectiveness of these measures in mitigating dam siltation within the watershed. The methodologies employed include the utilization of the MUSLE model, optimized with bathymetric surveys of the dam, to estimate the amount of sediment reaching the dam and derive the P-factor associated with the implemented anti-erosion measures. Additionally, the radioisotope technique was utilized to assess erosion rates at managed and unmanaged sites within the watershed. The results obtained using the MUSLE model and bathymetric data revealed a noteworthy reduction in mean annual soil loss within the timeframe of 2002–2010 to 2010–2013, resulting in a 13.9% decrease in sediment reaching the dam. Furthermore, variations in the P-factor of erosion control measures were observed, ranging from 0.31 to 0.52 during the respective periods. Utilizing the radionuclide 7Be, erosion rates ranging from 6.8 to 25.3 t.ha−1 were determined for the studied plots, facilitating the calculation of P-factors for specific erosion control measures. Significantly, gabion check dams displayed a P-factor of 0.47, dry stone barriers had a P-factor of 0.41, fruit trees with basins showed a P-factor of 0.51, and enclosures exhibited a P-factor of 0.67. These findings suggest a causal relationship between the implementation of erosion control measures and the reduction in sedimentation rates at the Allal El Fassi Dam, highlighting the interdependence between the two phenomena. [ABSTRACT FROM AUTHOR]

The morphodynamics of rivers in semiarid environments tend to be controlled by episodic flood events, but the precise nature of sedimentary processes and sediment source areas within catchments affected by episodic floods remains not well understood. This study presents geomorphological, sedimentary and mineralogical data from different river reaches along the semiarid Letaba River within Kruger National Park, northeast South Africa. Geomorphological and sedimentary data were used to evaluate river morphodynamic behaviour and identify the major controls on landform development. Mineralogical data (heavy minerals and trace elements) were examined from surface sediment samples from different river reaches to determine the potential source areas for sediment reworking within the catchment (channel bank, channel bed, tributaries) for flood-transported sediments. Results of this analysis on downstream reaches show catchment-averaged sediment contributions from the channel bed of 42.5%, tributaries of 35%, and channel bank of 22.5%. These sediment contributions likely arise as a result of the different flow conditions experienced in different locations of the river system during floods. However, there is significant variability between samples from individual reaches, likely related to valley width and bedrock vs sediment availability. The contributions of river sediments from different sources are conceptually developed through a model of sediment source variability at different hydrodynamic stages. This highlights the role of floods in reactivating non-perennial tributaries and adding new sediment into the main channel. Measurements of perennial channel storage, therefore, do not give the whole picture of total sediment availability or activation during floods. [ABSTRACT FROM AUTHOR]

The results of the study of bottom sediments and water of the estuary of the Grøndalen River (Grøn-Fjord, West Spitsbergen) are presented. The stratigraphic features of the sedimentary strata are determined. The chronology of changes in geoecological environmental conditions has been established using radioisotope dating methods. The main factors influencing sedimentation in the study area are air temperature and precipitation during the period of predominance of low temperatures. It is shown that climate fluctuations determine the chronological sequence of the sedimentation rate and the change of the lithotype of the bottom sediment toward fine fractions. [ABSTRACT FROM AUTHOR]

Naumure Multipurpose Project (NMP) featuring a 169 m high Concrete Face Rock Filled Dam (CFRD) is the proposed reservoir project in the West Rapti River with an installed capacity of 218.34 MW. Most of the rivers in Nepal carry significant sediment loads that will consequently catalyze reservoir sedimentation. This phenomenon prevails as the primary factor in reducing reservoirs useful life, making ineffective for both flood control and hydroelectricity generation. Ultimately, such process of sedimentation has adverse impacts on projects economic feasibility and long-term sustainability. Therefore, the objective of this research was to examine the expected sediment deposition pattern in the NMP reservoir throughout its operational period by employing 1D HEC-RAS model to simulate the sedimentation process. The model was simulated for 10, 20, 30, 40 and 50 years. Yang's equation as a sediment transport function, Active layer as a bed sorting method and Toffaleti as a fall velocity method were best suited for the river reach. The delta deposition was formed between 11 km and 22 km upstream of the dam region in the Jhimruk river, with the sediment deposition depth reaching peaks of about 23 m, 38 m, 39 m, 41 m and 49 m in 10, 20, 30, 40 and 50 years, respectively. Similarly, the delta deposition was formed between 13 km and 33 km upstream of dam region in the Madi river, with the sediment deposition depth reaching peaks of about 47 m, 62 m, 60 m, 68 m and 75 m in 10, 20, 30, 40 and 50 years respectively. Headcutting of delta deposition occurred between 20 and 30 year due to high flood during low stage of reservoir. Furthermore, the study revealed that about 6.22%, 11.61%, 15.94%, 22.96% and 25.65% of the storage capacity of NMP reservoir will be depleted in 10, 20, 30, 40 and 50 years respectively. [ABSTRACT FROM AUTHOR]

While the Cretaceous Normal Polarity Superchron has documented instances of brief reversed polarity intervals, the absence of accurate age determinations for such abrupt shifts poses a challenge in leveraging them as reliable reference tiepoints. This study presents a cyclostratigraphic analysis of gamma‐ray data from the DSDP Site 402A. The identification of Milankovitch cycles allowed us to construct a 405‐kyr astronomically‐tuned age model for two reversed events that occurred in the Aptian. Our results estimate an age of 117.03 ± 0.14 Ma for the Chron M"‐1r" or ISEA and 116.17 ± 0.14 Ma for reversal "2," with timespans of ∼20 and ∼10 kyr, respectively. Sedimentation patterns are influenced by orbital eccentricity cycles with an average sedimentation rate of 5 cm/kyr. The short time intervals related to these reversals exposes the difficulty in their detection in cores through paleomagnetic analysis as well as in deep‐tow surveys. Plain Language Summary: The Cretaceous Normal Polarity Superchron (CNPS) was characterized as a "quiet zone," which includes no geomagnetic reversals during ∼38 Myr. A number of studies propose significant fluctuations in geomagnetic intensity, with distinct features observed in paleosecular variations, including periods of reversal events, and the actual occurrence, timespan and ages for these rapid magnetozones have been under debate in literature. This paper provides the age and constrains the timespan of two of these debated reversals (i.e., M"‐1r" or ISEA, and "2") during the CNPS. The determination of the age of the reversals during the CNPS is a fundamental support for global correlations. Key Points: Orbital tuning for M‐1r (ISEA) has an age of 117.03 ± 0.14 Ma and a timespan of 20 kyrThe reversal "2" has an age of 116.16 ± 0.14 Ma and a minimum timespan of 10 kyrDSDP Site 402A has an average 5 cm/kyr sedimentation rate and eccentricity Milankovitch cycles rules sedimentation patterns [ABSTRACT FROM AUTHOR]

Controlled sediment flushing operations (CSFOs) allow to recover reservoirs storage loss while rebalancing the sediment flux interrupted by dams but, at the same time, may cause unacceptable ecological impact. In this study, we investigated the responses of the food web of an upland stream to a CSFO, focusing on the effects of fine sediment deposition detected in three different mesohabitats, i.e., a pool, a riffle, and a step-pool. The field campaign lasted two years and included repeated measurements of fine sediment deposits, and sampling of periphyton, benthic macroinvertebrates and fishes. A moderate and patchy deposition occurred due to the CSFO with short and medium-term ecological impact on the lower trophic levels of the food web, which may affect the whole ecosystem functioning. The monitoring of all available mesohabitats in the investigated stream allowed to detect variations in the ecological response to CSFO, providing a more adequate assessment of the impact. As expected, sedimentation was larger in the pool but, in contrast to our hypotheses, the impact was lower and the recovery was longer for the benthic organisms inhabiting the riffle. In the case of fishes, no lethal impact of both brown trout and bullhead was recorded in the short term but the occurrence of longer lasting effects could not be excluded. To date, this is one of the few studies dealing with a detailed integrative assessment of the downstream impact of sediment management from reservoir on both abiotic and biotic components of stream ecosystem. [ABSTRACT FROM AUTHOR]

ABSTRACT Saddle dolomite is a Ca–Mg carbonate characterized by curved crystal faces, curved cleavage and sweeping extinction under cross‐polarized light. Saddle dolomite and, generally, Ca–Mg carbonates with curved crystal faces, are often assigned to the burial (hydrothermal) realm and serve as proxy archives for hydrogeochemical processes in sedimentary basins and orogens. At present, the physicochemical conditions leading to the formation of these peculiar warped carbonates are unclear, and the mechanisms inducing the curvature of their crystal lattice are debated. This study uses laboratory experiments to assess the factors controlling the formation of carbonates with curved crystal faces as a function of fluid temperature, reactant size, fluid salinity and fluid Mg : Ca. Results show that a range of magnesium calcites with curved surfaces form at elevated temperatures (ca 220°C) from calcium‐rich fluids (Mg : Ca = 0.43) within a wide range of fluid salinities (5 to 40 wt.%). Magnesium calcites that nucleate epitaxially on rhombohedral or saddle dolomite substrates exhibit warped surfaces, while those that nucleate on calcite seeds form flat surfaces. Although the two crystal habits can co‐occur, Mg‐calcites with curved crystal faces (Mg : Ca of 0.35 to 0.40) tend to be more calcium‐rich than those with flat faces (Mg : Ca of 0.58 to 0.74). In experiments with higher fluid temperature (230°C), calcite reactants undergo replacement by dolomite exhibiting planar crystal faces. The results collectively indicate that the formation of Ca–Mg carbonates with warped surfaces is likely related to a combination of geochemical and physical parameters and various threshold limits, as opposed to one specific parameter, for example, elevated fluid temperature, as is commonly reported in the literature. Although most of the present experimental precipitates are disordered magnesian calcites with bent crystal faces, it is reasonable, at the level of a tentative working hypothesis, that these represent precursors of many ancient saddle dolomites commonly found in burial settings. [ABSTRACT FROM AUTHOR]

High-latitude ecosystems have been overlooked in carbon budgets, which traditionally focus on mangroves, salt marshes, and seagrasses. The benthic assemblages and their Nature Contributions to People in Namuncurá – Burdwood Bank I and II, two offshore sub-Antarctic Marine Protected Areas (MPAs), are the conservation values. Here we show that the carbon reservoirs of these MPAs can be greater than those of their Antarctic counterparts, which, together with their extension, emphasize the need to maintain their protected status. Considering their total area, these MPAs stored in biomass 52,085.78 Mg C, corresponding 34,964.16 Mg to organic carbon (OC) and 17,121.62 Mg to inorganic carbon (IC). Surficial sediments stored 933,258,336 Mg C with 188,089,629 Mg of OC and 745,168,707 Mg of IC. However, when accounting for CO2 production through CaCO3 precipitation, the IC fractions decrease to 3,150.37 Mg C and 137,111,042 Mg C for biomass and sediments, respectively. We assume low sediment deposition due to the oceanic location, as direct sedimentation rates for these areas are unavailable. Most blue carbon assessments have focused solely on OC, despite the formation of CaCO3 releases CO2, decreasing net carbon storage. We compared various approaches for incorporating carbonates into carbon estimations. These results underscore the importance of including IC into carbon assessments and highlights the importance of sub-Antarctic benthic ecosystems as nature-based solutions to climate change. [ABSTRACT FROM AUTHOR]

Multiple vortex flow patterns are commonly observed in lateral pumping station forebays, particularly in basins with high sediment concentrations. These patterns can lead to pump blockage, sediment deposition, and other issues that disrupt pump station operations. The water-sediment two-phase flow in lateral pumping station forebays is significantly influenced by the start-up combination, yet our understanding remains limited. To address this, the mixture multiphase flow theory is introduced to describe water-sediment dynamics, and the mathematical model is validated with experimental data. By analyzing the characteristics and formation mechanisms of large vortex and multiple small vortex regions in the original scheme, nine different start-up combination schemes were proposed. The research results indicate that, due to the narrow channel and slope effect in the lateral forebay, some of the gravitational potential energy of the water-sediment mixture is converted into kinetic energy upon entering the forebay, thereby increasing the velocity in the main flow area. Additionally, due to the friction and dissipation effects of the two sidewalls, a pressure difference is generated in the main flow area, resulting in the formation of multi-level vortices. Furthermore, the various types of proposed start-up combinations can optimize the flow patterns in the forebay to a certain extent. The preferred scheme improved the uniformity of flow velocity by 18.63% and increased the deviation angle by 17.62°, resulting in a 75.47% reduction in vortex area compared to the original scheme. These research results provide theoretical guidance for optimizing start-up combinations and reorganizing flow field structures to achieve hydrodynamic dredging effects. [ABSTRACT FROM AUTHOR]

In light of the forebay of a lateral pump station in Shaanxi Province, numerical simulation and engineering tests were employed to analyze the correlation between the formation of multiple vortices and sediment deposition in the lateral forebay. Building upon this foundation, a total of 24 distinct rectification measures were proposed to scrutinize the alteration in flow regime within the lateral forebay, followed by an engineering test to validate the optimal scheme in the absence of rectification measures. The findings from the engineering test of the lateral forebay were consistent with the outcomes of the numerical simulation. This marked the inaugural proposition of a trapezoidal array clapboard within a lateral forebay. By adjusting the position, rotating the clapboard angle, and selecting the optimal scheme 24, the flow velocity uniformity at section C1-2 reached 93.16%, the deflection angle measured 94.32°, and the vortex area reduction rate was 87.73%, significantly mitigating the vortex impact on this section. Within section C1-3, the flow velocity uniformity attained 96.58%, the deflection angle measured 86.43°, and the vortex area reduction rate in this section amounted to 81.26%. Through the analysis of these two sections, the scheme's accuracy was validated. Additionally, the sediment deposition thickness decreased by 2.39 m under scheme 24, thus ensuring favorable operational conditions for the inlet forebay of the lateral pump station. [ABSTRACT FROM AUTHOR]

Laboratory studies, which field trial was conducted in the 2020-2021 growing season at the Eastern Mediterranean Agricultural Research Institute, were conducted at Gümüşhane University. In this study, the findings showed that urea was used as the top fertilizer in different growth stages of the 'Yakamoz' bread wheat cultivar used as material, and the effects of urea application periods and flour type, on the quality traits, such as dry matter, ash, protein, acidity, fresh and dry gluten, gluten index, sedimentation, and falling number were investigated. For this purpose, in addition to the control application, tillering, stem elongation, milky and dough stages were chosen as urea application periods. Laboratory studies were carried out in randomized plots using the split-plot design with three replications. In the present study, all quality traits showed statistically significant differences for urea application periods; these values were ranged as follows: Dry matter: 90.20-90.77%, ash: 1.037-1.213%, protein: 14.01-15.15%, acidity: 0.037- 0.056%, wet gluten: 41.49-43.67%, dry gluten: 14.75%-15.46, gluten index: 69.28-80.38%, sedimentation: 20.0-21.0 mL, late sedimentation: 23.5-29.8 mL and falling number: 753.8-881.7 s. In addition, other quality parameters except dry matter, protein and sedimentation changed statistically for flour type. Accordingly, whole wheat flour for ash (1.443%), acidity (0.051%) and gluten index (82.53%); white flour showed high values for wet (44.90%) and dry (15.96%) gluten, late sedimentation (35.60 mL) and falling number (836.4 s). As a result, while applying urea as a top fertilizer, it is recommended to choose the stem elongation stage for high gluten index, delayed sedimentation and protein, and the dough maturity stage for high dry matter. It would be appropriate to represent more genotypes and different nitrogen sources in further studies to be more inclusive. [ABSTRACT FROM AUTHOR]

The occurrence and abundance of Astrospartus mediterraneus (Risso, 1826) have significantly increased in the last three decades in several areas of the Mediterranean Sea. In the Tavolara–Punta Coda Cavallo Marine Protected Area (NE Sardinia, Tyrrhenian Sea, Mediterranean Sea), 60 specimens were observed mainly on the granitic shoals of the Tavolara Channel, an area characterized by very intense currents and high sedimentation. The basket stars were mainly found living as epibionts of gorgonians (Eunicella verrucosa, Paramuricea clavata and Leptogorgia sarmentosa) and massive sponges (Spongia officinalis, S. lamella, Sarcotragus foetidus). We also documented 21 small specimens (3–20 mm in diameter of the oral disc) observed in June 2024 between 27 and 52 m depth on E. verrucosa and P. clavata colonies. The bimodal size-frequency distribution of these specimens suggested that, probably, specimens belong to two different reproductive events occurring in spring 2023 and 2024. [ABSTRACT FROM AUTHOR]

In recent years, Conversational Analysis (CA) has seen an increasing interest in longitudinal studies (Deppermann & Pekarek Doehler, 2021). The recurrent experience of interactional practices leads interactants to develop routines that may sediment into entrenched patterns over time (Dreyer, 2022). Longitudinal CA thus aims to track the emergence and sedimentation of interactional practices over time. In this contribution, we analyse interactional practices of participation in play-situations. Participation in joint activities is a universal form of human sociality (Goodwin & Goodwin, 2005). Here, we focus on how children perform their own agentive participant's work and how mothers support their children in doing so. Investigating a longitudinal data set of mother-child play-interactions at ages 1 and 5, we ask whether participation patterns emerge as early as in the first year and are sedimented in the fifth year, as well as whether the synchronisation of embodied action provides crucial resources for the achievement of active participation in joint activities. [ABSTRACT FROM AUTHOR]

We use the complex model combining the spatially 2D bottom material transport model, the 3D suspension transport model, and the 3D hydrodynamics model. The results of numerical experiments obtained on the basis of a complex model for calculating sedimentation and changes in the relief of the bottom surface are presented, and the intensity of abrasion for the coastal zones of the Tsimlyansk reservoir with the most intense geoecological situation is estimated. Based on the developed software package, calculations of the processes of coastal erosion and changes in the bottom relief were performed, taking into account the spatial and temporal variability of relief formation. [ABSTRACT FROM AUTHOR]

Residual dosage has a significant impact on the settling characteristics of coal slurry flocs and the sedimentation efficiency of coal slurry. This study conducted sedimentation stirring experiments to measure the supernatant grayscale, floc size, settling velocity, and residual anionic polyacrylamide (APAM) under varying energy inputs. The investigation focused on the correlation between different levels of APAM residual and the settling characteristics of coal slurry flocs. The results show that having APAM residuals in the first three stages helps with sedimentation. This leads to lower residual levels, higher grayscale in the supernatant, bigger floc sizes, and better settling velocities. However, in the fourth stage, as APAM residual levels increased once more, the supernatant grayscale decreased linearly, floc breakup became severe, and settling velocities neared stagnation. In the second stage, a correlation was noticed between higher APAM residual levels and better settling properties of coal slurry flocs. By studying residual dosage and energy input, guidance on how to optimize the sedimentation efficiency of the thickener and reduce dosage can be provided. [ABSTRACT FROM AUTHOR]

The present paper addresses the effect of placing an intake, as a diversion structure, in different positions and with various angles in a 180° bend to investigate the scour depth around a circular pier in an SSIIM2 numerical model. The simulation was conducted by placing the intake at the 75°, 90°, 115°, 135°, and 150° positions with 45°, 60°, and 90° angles. The results indicated that the greatest effect was associated with the installation of the intake with a 90° angle at the 135° position, which decreased the maximum scour depth by a considerable amount, about 70%, compared with the bend without an intake. However, the maximum scour depth occurred with the installation of the intake at the 150° position with an intake angle of 45° and increased by 20% compared to the bend without an intake. Furthermore, the maximum and minimum scour hole wall slopes around the pier in the case of the bend with an intake respectively increased by 6.24 times and decreased by 5.1 times compared to the bend without an intake at the upstream pier. The maximum sedimentation height around the pier decreased by about 40% in the bend with an intake compared to the one without an intake. [ABSTRACT FROM AUTHOR]

The common spur dikes, which are used for river path control and bank protection, are utilized without any slots or with additional structures such as a collar or vane. The present research has been conducted to optimize the slot position in the spur dikes' body, reduce the scour depth, and improve the sedimentation conditions using the CFD model. The numerical result was compared with the Nayyer et al. 2019. A numerical and experimental investigation of the effects of combination of spur dikes in series on a flow field. Journal of the Brazilian Society of Mechanical Sciences and Engineering, 41(6), 1–11) experimental outcome. Results showed that the (LS-W-Wi, TS-W, TS-W-Wi) combination contained the slots in the web and wing of the first and third spur dike, and the slot at the web of the middle spur dike was found as the best combination of slots under clear-water conditions. This combination was conducted to reduce the scour depth by 6.8% and increase deposition by 52% compared to the spur dikes without slots, which causes reducing scour depth and an increase in the sedimentation rate of materials between two consecutive spur dikes in series. Also, the maximum scours depth decreases by up to 20%. The results revealed that the presence of slots in spur dike and their different positions have complicated and considerable influences on the form and morphology of the bed. [ABSTRACT FROM AUTHOR]

Rapid urbanization has an accelerated impact on catchment hydrology and geomorphology due to land use and land cover changes as a result of anthropogenic development activities in river catchment areas that cause increased surface runoff and higher sediment yield. The present study investigates the channel changes and sediment transport phenomena, including bed material movement from the upstream to the estuaries of the Pahang River Basin, Peninsula Malaysia. The river geometry survey associated with the spatial variation in sediment transport has confirmed that changes in river bed profile occur due to the erosion and sediment deposition along the Pahang River. The sediment size distribution for the Pahang River was very coarse sand and gravel after the December 2014 flood. The river geometry survey showed a gentle slope that can induce lower discharge typical of alluvial rivers relating to flood events. Quantitative assessment of sediment load is, therefore, of critical importance for future river basin management. [ABSTRACT FROM AUTHOR]

This is the second of a two-part New Zealand Journal of Geology and Geophysics Special Issue on understanding sedimentary systems in Aotearoa-New Zealand's Hikurangi Subduction Margin (HSM). This volume includes six research papers that explore sediment-tectonic interactions operating over a range of spatio-temporal scales. We take a distinctive perspective moving from the subduction deformation front in the Hikurangi Trough, upslope to the subduction wedge, and onshore to the Coastal Ranges. Temporally, papers span the onset of subduction in the Miocene, to disentangling provenance of turbidity currents triggered by the 2016 CE Kaikōura Earthquake. Collectively, the studies in the special issue reveal a complicated and continually evolving margin, where active tectonics and volcanism, coupled with vigorous climatic and oceanographic drivers, modulate erosion, transport, and depositional cycles of vast volumes of terrigenous sediment into ocean basins. Despite decades of significant research advances in our knowledge of the HSM, considerable scope remains for future work. A deeper understanding of fundamental tectonic-sediment interactions operating on active margins, along with the significant geohazards they pose remain outstanding research needs. Collectively, Volumes 1 and 2 highlight enduring interest in the HSM as a globally important natural laboratory for the study of subduction zone geoscience. [ABSTRACT FROM AUTHOR]

Sedimentological and rock magnetic analysis was performed on 67 turbidite samples recovered from Lithostratigraphic units I–III at IODP Site U1520 with the aim to characterise the sedimentary processes and post-depositional diagenesis within a Quaternary sequence in the Hikurangi Trough, New Zealand. Lithostratigraphic Unit I was rapidly emplaced with frequent turbidite deposition with high sedimentation rate (∼1.9 m/kyr). In contrast, in units II–III, the turbidites were finer grained and more thinly bedded, and were deposited at less than half the deposition rate of Unit I. The turbidites were classified into three clusters based on the magnetic properties. Clusters 1 and 2 are characterised by a high coercivity and SIRM/χ, but low to moderate Bcr/Bc. The recognition of gyroremanent magnetisation acquisition in their clusters indicates the diagenetic sulfidization. Cluster 3 was represented by low coercivity and SIRM/χ, but high Bcr/Bc, indicating lack of sulfidization. Restricted occurrence of Cluster 3 in Unit I may be ascribed to the high sedimentation rate, which prevents sulfidization at the sulfate–methane transition zone. Degree of sulfidization might be related with sedimentary features of turbidites in the trough, such as grain size, bed thickness and depositional rate. [ABSTRACT FROM AUTHOR]

The Albian–Aptian Goru Formation represents a fluvio-deltaic reservoir in both the Central and Southern Indus Basin, Pakistan. Using high-resolution core data, this study provides comprehensive insights into the depositional environment and its role in influencing reservoir heterogeneities in the studied formation. The sedimentological investigations demonstrate five lithofacies, namely, (i) massive sandstone (Sm), (ii) horizontal to low-angle planar laminated sandstone (Sl), (iii) planar cross-laminated sandstone (Sc), (iv) heterolithic beds (Hw and Hr), and (v) massive mudstone (Mm). Facies associations reflect shallow marine depositional settings varying from deltaic in the NE to strand plain in the SW. The framework grains of the established lithofacies exhibit quartzo-feldspathic petrofabrics, which have been sourced from stable craton-continental block settings. The petrophysical data in the core depth zone show high shale content in Well-A and lower parts of Well-B. In Well-A, the crossover between the density and neutron logs is not observed, which suggests unsaturated sands, while Well-B exhibits a permeable zone as indicated by neutron-density crossover, low gamma ray values, and relatively high porosity. The petrographic analysis and scanning electron microscopy indicate high effective porosities contributed by both primary (intergranular and intercrystalline) and secondary porosity (owing to fracturing and dissolution). The upper part of Well-B shows high porosity values up to 28% due to highly fractured quartz. Porosity values are low in the lower parts of the Well-A and Well-B due to intensive calcite cementation, chlorite recrystallization, proto matrix as well as pseudo matrix. This suggests that both Well-A and Well-B have a common source but the reservoir properties can be attributed to the depositional and post-depositional variations in the petrofabric of the studied lithological units. The Cretaceous Goru Formation in Southern Indus Basin, the Pariwar formations in Jaisalmar Basin, and Bhuj Formation in Kutch Basin share same geological history and sedimentary processes. Thus, these studies can be utilized in the exploration of Cretaceous reservoirs in these basins. [ABSTRACT FROM AUTHOR]

Investigating the geochemical composition of bulk sediments stands as a crucial method for unraveling the complexities of various sedimentary processes. However, the intricacies arising from extensive datasets and alterations in sediment due to diverse factors often impede the clear identification of underlying patterns in geochemical fluctuations. In addressing these, employing multivariate statistical analyses has proven to be an invaluable tool for elucidating intricate patterns within large dataset. In this study, we focus on the utilization of Principal Component Analysis (PCA), a multivariate statistical technique, to uncover the underlying sedimentary processes influencing distinct geochemical dataset. Specifically, our attention is directed towards the examination of geochemical data from the previously published geochemical data of metasediments from Shimla and Chail group (referred to as SCM) and the mudflat sediments of Diu Island (referred to as DMS). Our PCA outcomes reveal that the initial three principal components (PC1, PC2, and PC3) account for 52.51% and 79.30% of the total variance within the SCM and DMS geochemical data, respectively. Notably, the negative loading of SiO2, alongside positive loadings of incompatible elements and those associated with mafic rocks on PC1 within the SCM dataset, indicates sediment origins ranging from felsic to intermediate sources. Additionally, the coexistence of Th, U, Zr, and Sc, exhibiting positive loadings in PC1 and PC2, suggests a significant influence of reworking and recycling from felsic to intermediate sources. In the context of the DMS dataset, PCA analysis highlights the dominant influence of in-situ productivity and mafic sediment sources along the positive axis of PC1. Conversely, the negative axis of PC1 is shaped by intermediate and potentially other sources. Further granularity in interpretation reveals the positive axis of PC2 being attributed to weathering proxies, while the dominance of plagioclase minerals in the clayey fraction controls the positive axis of PC3. Through this investigation, our study underscores the essential role of PCA-assisted geochemical data analysis in unraveling the intricate web of processes contributing to the variance observed within sedimentary systems. By effectively distilling the multifaceted factors driving geochemical variability, this approach emerges as a pivotal asset in enhancing our understanding of sedimentary dynamics. [ABSTRACT FROM AUTHOR]

The article questions the paradigmatic nature ascribed to "the zone"—and the concomitant dismissal of the camp's—by some analyses of the politics of capital's operations, and problematizes the very notion of the paradigm. Elaborating on previous reflections concerning contemporary agro-industrial zones in Italy, the article rethinks camps against state-centric and exceptionalist readings that consider them purely as sites of exclusion. At the same time, it retains a stress on the symbolic dimension of forms of containment and extraction, going beyond a narrow political-economic approach. The zone and the camp, it is argued, are mutually imbricated "infrastructure spaces" of present-day agro-capital's operations, which, however, result from the sedimentation of spatialized techniques for labor disciplining, reproduction, and containment that have developed alongside capitalist forms of agriculture throughout the contemporary period. The camp is thus defined as a function of the political, sovereign dimensions of extraction, that may operate within but also beyond the state. Furthermore, it is underlain by differential attributions of humanness, and therefore by a specific biopolitical anthropology. Engaging in a genealogy of the (humanitarian and/as labor) camps that today proliferate in agro-industrial zones, I argue that to understand the spatial formations emerging from and sustaining the politics of contemporary capital operations a recursive analytics is necessary, that thus questions the purchase of paradigms on the grounds of their atemporality and complicates the positing of mere historical continuities. [ABSTRACT FROM AUTHOR]

Many tidal marshes have been lost by past land use changes, but are nowadays increasingly restored and created to provide valuable ecosystem services such as nature‐based flood and erosion protection along estuarine shorelines. To be functional for flood and shoreline erosion protection, restored and created tidal marshes should develop erosion resistant sediment beds. Here, we investigated which factors drive the spatial variations in sediment strength and erosion resistance in a developing tidal marsh restoration site. Our results show that decreasing tidal inundation frequency, decreasing sedimentation rate, and better drainage led to stronger consolidation in deeper sediment layers. This consolidation resulted in greater sediment strength, quantified here by shear strength and penetration resistance. Generally, sediment strength was greater when sediment had higher bulk density, while a higher water and fine fraction (= clay and silt) content decreased sediment strength. Overall, all measurement locations were relatively erosion resistant, likely caused by the dense root network and cohesive sediment. To restore or create resilient tidal marshes for nature‐based flood and shoreline erosion protection, we should thus aim for sites with relatively low tidal inundation frequency, moderate sedimentation rates, and cohesive sediment mixtures of clay, silt, and sand, which are well drained and have potential for vegetation establishment. These conditions have a high likelihood of resulting in restored or created tidal marshes that contribute to nature‐based flood and shoreline erosion protection. [ABSTRACT FROM AUTHOR]

Sedimentary landforms on Earth and other planetary bodies are built through scour, transport, and deposition of sediment. Sediment connectivity refers to the hypothesis that pathways of sediment transport do not occur in isolation, but rather are mechanistically linked. In dryland river systems, one such example of sediment connectivity is the transport of fluvially deposited sediment by wind. However, predictive tools that can forecast fluvial‐aeolian sediment connectivity at meaningful scales are rare. Here we develop a suite of models for quantifying the availability of river‐sourced sediment for aeolian transport as a function of river flow, wind regime, and land cover across 168 km of the Colorado River in Grand Canyon, USA. We compare and validate these models using topographic changes observed over 10 years in a coupled river sandbar‐aeolian dunefield setting. The models provide a path forward for directly linking fluvial hydrology with the management and understanding of aeolian landscapes. Plain Language Summary: Landscapes on Earth are built from sediment, which is deposited by a variety of processes, especially water and wind. In rivers located in dry regions, sediment is deposited by flowing water during river floods. Once this sediment dries, it is often then moved by wind across the landscape. Although we frequently observe this sediment connectivity between water and wind, we are not currently able to predict when and where windblown transport of river‐deposited sediment may occur. We used maps of sand in Grand Canyon along 168 km of the Colorado River, along with records of river flow, wind speed, and vegetation cover, to develop four models that predict how much sediment is available for wind to move. We compared the results of these models to actual windblown sediment transport at a study site in Grand Canyon, finding that when models predicted more sand was available at the site, we also observed more landscape changes there which were due to wind. Our research makes it possible to understand how changes in river flows affect the amount of sediment moved by wind. Key Points: We developed four methods for modeling the extent of exposed, bare sand available for windblown transport in river valleysOur models employ data on river flow, land cover, wind velocity, and vegetation to predict exposed, bare sand extent at corridor scalesWhere models predict increased areal extent of bare sand, we also observe a greater volume of topographic changes driven by wind [ABSTRACT FROM AUTHOR]

Hydrological drought is a pervasive and reoccurring challenge in managing water resources. Reservoirs are critical for lessening the impacts of drought on water available for many uses. We use a novel and generalized approach to identify periods of unusually low reservoir storage—via comparisons to operational rule curves and historical patterns—to investigate how droughts affect storage in 250 reservoirs across the conterminous U.S. (CONUS). We find that the maximum amount of water stored in reservoirs is decreasing, and that periods of unusually low storage are becoming longer, more severe, and more variable in (a) western and central CONUS reservoirs, and (b) reservoirs with primarily over‐year storage. Results suggest that reservoir storage has become less reliable and more vulnerable to larger deviations from desired storage patterns. These changes have coincided with ongoing shifts to the hydroclimate of CONUS, and with sedimentation further reducing available reservoir storage. Plain Language Summary: Drought in water systems is a major challenge in managing water resources. Reservoirs are important as they can lessen the impacts of drought on water availability for many users. However, they are impacted by drought as well. We use a novel and generally applicable method to identify when reservoir storage is unusually low, potentially from drought, at 250 reservoirs across the conterminous U.S. We find that the maximum amount of water stored in reservoirs is decreasing across the U.S. We also find that periods of unusually low storage are becoming longer and more severe in western and central U.S. regions as well as for certain types of reservoirs. This suggests that reservoir storage may be less reliable and more vulnerable to extreme conditions and may be further impacted by changing climate and hydrology across the U.S. and by sediment building up behind reservoirs. Key Points: Low‐storage periods are longer, more severe, and more variable in over‐year storage reservoirs and in the western and central CONUSLonger periods of low storage for some regions in recent years suggests decreased reservoir reliability in a changing hydroclimateMaximum annual storage is also declining across CONUS, furthered by storage losses from sedimentation [ABSTRACT FROM AUTHOR]

The investigation results of granulometric composition, zeta potential, sedimentation stability, and viscosity of some water-coal suspensions made of Ukrainian coal from the “Stepova” mine, Lviv-Volyn region, are reported. The most effective granulometric composition of the water-coal suspension consisting of the rough and fine fractions is found from the analysis of the abovementioned physicochemical characteristics of the suspensions. Based on the complex investigation of the zeta potential of the dispersed phase particles, viscosity, and sedimentation stability of the suspensions, it was established that the best technological effectiveness can be expected for the suspensions containing 60% of the rough fraction (sized between 100 and 250 µm) and fine particles sized between 20 and 40 µm. In such systems, the particles form a quasi-stable structure, where the lower-charged small particles are located in the interparticle space between the highly charged bigger particles. All particles bear the same charge, increasing the system’s sedimentation stability and avoiding decomposition for at least 5 days. This time seems reasonable for the preparation, storage, and pumping of the suspensions while their viscosity and stability meet the relevant technological requirements. [ABSTRACT FROM AUTHOR]

Spaceborne spectroscopic imaging offers the potential to improve our understanding of biodiversity and ecosystem services, particularly for challenging and rich environments like mangroves. Understanding the signals present in large volumes of high-dimensional spectroscopic observations of vegetation communities requires the characterization of seasonal phenology and response to environmental conditions. This analysis leverages both spectroscopic and phenological information to characterize vegetation communities in the Sundarban riverine mangrove forest of the Ganges–Brahmaputra delta. Parallel analyses of surface reflectance spectra from NASA's EMIT imaging spectrometer and MODIS vegetation abundance time series (2000–2022) reveal the spectroscopic and phenological diversity of the Sundarban mangrove communities. A comparison of spectral and temporal feature spaces rendered with low-order principal components and 3D embeddings from Uniform Manifold Approximation and Projection (UMAP) reveals similar structures with multiple spectral and temporal endmembers and multiple internal amplitude continua for both EMIT reflectance and MODIS Enhanced Vegetation Index (EVI) phenology. The spectral and temporal feature spaces of the Sundarban represent independent observations sharing a common structure that is driven by the physical processes controlling tree canopy spectral properties and their temporal evolution. Spectral and phenological endmembers reside at the peripheries of the mangrove forest with multiple outward gradients in amplitude of reflectance and phenology within the forest. Longitudinal gradients of both phenology and reflectance amplitude coincide with LiDAR-derived gradients in tree canopy height and sub-canopy ground elevation, suggesting the influence of surface hydrology and sediment deposition. RGB composite maps of both linear (PC) and nonlinear (UMAP) 3D feature spaces reveal a strong contrast between the phenological and spectroscopic diversity of the eastern Sundarban and the less diverse western Sundarban. [ABSTRACT FROM AUTHOR]

This study presents the analysis of the taphonomical processes at the Rosario Mine (Valdeteja Formation, León). The studied beds are an ensemble of normal graded sequences comprised of rudstones and grainstones that pass upwards to packstones and finally to marls. The last sequence culminates in a 3 m thick bed of carbonaceous shales with coal balls. In the limestones there are evidences of breakage, resedimentation and even some reworking. The top of the packstones and the marls show hummocky cross stratification and abundant burrows. The fossils in the limestones represent an allochthonous assemblage, while the marls contain a mostly autochthonous assemblage, typical of a deep marine environment.These sequences were deposited in a deep area of a tropical carbonate platform in a foreland basin, and they resulted from mass flows triggered by large waves followed by quiet background environmental conditions. Tsunamis or cyclones could be the events originating these sequences. The characteristic of the deposit and the palaeogeographical framework have been examined to try to differentiate between these events. The climate and tectonic context during the sedimentation support both possibilities, while the deep environment and the amount of plant remains dragged to the sea seem more consistent with tsunamis. [ABSTRACT FROM AUTHOR]

The study examines the specific features of the structure and composition of strata of the Tyushevskaya basin of Eastern Kamchatka, which formed at the site of the Vetlovsky basin, which is marginal marine in nature. This structure probably began to form in the Late Eocene–Oligocene. A scheme for its evolution is proposed. In the modern structure, sediments of the Tyushevskaya basin overlie the material complexes and structures of various terranes and participate in the accretionary structure of the region. Sedimentary formations are predominantly facies-variable coarse coastal-marine and/or deltaic sediments, which change upsection to deeper-water flysch formations. Oil-bearing manifestations are associated with these complexes. [ABSTRACT FROM AUTHOR]

Channel deposits from meandering rivers have proven to be far more complex than the well‐known lithofacies model consisting of coarse‐grained channel, gravelly channel‐lag and fine‐grained overbank deposits. Sharp bends in rivers are subject to different hydraulic processes than bends with lower curvatures, enabling erosion of inner banks and deposition of fine‐grained sediments in the outer bend, resulting in downstream migration of river bends. This phenomenon is known as counterpoint deposition, forming counterpoint bars. This research investigates whether scroll bars associated with a sharp bend in the Lower Rhine River, The Netherlands, are such a counterpoint‐bar deposit. A counterpoint bar is expected based on: (i) the surface morphology of the scroll bar; (ii) the confinement of the river course by an ice‐pushed ridge resulting in a sharp bend; and (iii) the archaeological context of successive Roman settlements atop the ice‐pushed ridge, potentially moving downstream with the migrating river bend. This hypothesis is tested through detailed borehole descriptions combined with optically stimulated luminescence dating, the latter being a novel approach to identifying counterpoint deposits. The deposits consist of clays and sandy clays with fine sand laminations, and sporadic larger sand bodies. Further upstream these deposits grade into channel deposits dominated by coarser sands with gravels. These lithologies are explained using earlier proposed mechanisms for counterpoint formation; substrata match those described in previously studied counterpoint deposits and their point bar counterparts. Optically stimulated luminescence dates indicate that the Lower Rhine River bend migrated downstream, confirming counterpoint deposition. A migration rate of 1.93 m/year was established through weighted linear regression. This study demonstrates the potential of optically stimulated luminescence dating to investigate counterpoint bar presence. The identified counterpoint bars and associated bend migration provide insight into meandering river dynamics that is crucial for river management and in aiding river restoration and rewilding initiatives. [ABSTRACT FROM AUTHOR]

Both catchment geology and land use surrounding a stream will affect the degree of fine sediment deposition from erosion and its consequent impacts on stream macroinvertebrate communities. While geology and land use have been shown to impact stream communities individually, their interaction has received less attention.We investigated the interaction between geology and land use on stream macroinvertebrate communities in the Tairāwhiti Region, New Zealand. The region has streams that drain harder sandstones and softer shales and mudstones, the latter having some of the highest erosion rates in the world. Macroinvertebrates were sampled each year between 2016 and 2018 at 80 sites in exotic forest, indigenous forest and pasture streams that drained hard or soft geology catchments.Conductivity in pasture and exotic forest streams was nearly twice as high as in indigenous forest streams and higher in soft than hard sediment streams. Deposited sediment cover was greater in soft than hard sediment streams, and greater in pasture and exotic forest streams than in indigenous forest streams. Periphyton cover did not differ between land uses but was higher in soft sediment streams.Ecological health was higher in the indigenous forest sites, intermediate in exotic forest sites and lowest in pasture streams. Biological indices were also higher within each land use in streams draining hard than soft sediment streams. Invertebrate communities appear to be determined primarily by the amount of deposited fine sediment and conductivity, both of which are higher in soft than in hard bottom streams, and in exotic forest and pasture streams.Synthesis and applications: Our results illustrate a complex and strong interaction between geology and land use and the consequent impact on stream macroinvertebrate communities. The combination of soft bottom streams with pasture or exotic forest land use is more detrimental than in similar hard bottom streams. Therefore, regulations for the management of any given land use need to be much stricter in catchments dominated by soft sediment geology. [ABSTRACT FROM AUTHOR]

The concentrations and composition of hydrocarbons (aliphatic, AHCs, and polycyclic aromatic, PAHs) are determined using molecular markers in bottom sediments of the Greenland–Norwegian basin and the Barents Sea (during the 84th cruise of the R/V Akademik Mstislav Keldysh in 2021). The research covered the deep-sea part of the Greenland Basin, the northern part of the East Greenland Ridge, the near-fault zone in the area of the junction of the Mohns and Knipovich ridges, the Western and Northwestern extremities of the Svalbard continental shelf (the Vestnes Ridge, the Ermak Plateau, the Sofia Basin, and the Hinlopen Trough), the Fram Strait, the Orly trough area with the intersection of the Erik-Eriksen trough, and the central part of the Barents Sea. The surface bottom sediments are found to contain a wide range of concentrations of Corg (0.25%–2.71%), AHCs (7–182 μg/g), and PAHs (23–1918 ng/g). The distribution of HCs is determined by the processes occurring in the sedimentary stratum (changes in Eh and fluid flows), and, to a lesser extent, by the lithotype of sediments. Therefore, in the sedimentary stratum, autochthonous components form in the composition of alkanes and naphthalenes form in the composition of PAHs. [ABSTRACT FROM AUTHOR]

• A novel three-equation two-phase flow model is proposed for sedimentation and consolidation. • Fluid pressure increases with initial sediment concentration, necessitating incorporation of non-hydrostatic pressure. • Inertial effects become significant with larger grains, indicating the need to incorporate inertial forces. Sedimentation and consolidation, a multi-physical phenomenon of great significance in aquatic environments, usually involves dynamic pore pressure, inertial effects, fluid-particle interphase interaction and solid stress. However, simplified models for sedimentation and consolidation typically assume hydrostatic mixture pressure and neglect inertial effects without proper justifications. Here, a one-dimensional three-equation two-phase flow model (TTP) is proposed for sedimentation and consolidation, which directly resolves dynamic fluid pressure and inertial terms. The present TTP model is benchmarked against a series of experimental cases and two existing four-equation two-phase flow (FTP) models. It features encouraging performance as compared to measured data and computed results of the existing FTP model. Furthermore, the present TTP model shows superior computing efficiency over the FTP models. To investigate the influences of inertial effects and non-hydrostatic mixture pressure, two simplified versions of the TTP model are constructed and compared with the TTP model. It is shown that incorporating inertial effects and non-hydrostatic fluid pressure are important for accurately predicting the sedimentation-consolidation process. The present study facilitates a promising framework for modelling sedimentation and consolidation, thereby supporting effective sediment management. [ABSTRACT FROM AUTHOR]

Nanofluids have gained considerable attention as potential alternatives to pure fluids in cooling systems, particularly in boiling flow systems operating in two-phase vapor–liquid conditions. While nanofluids enhance heat transfer in cooling systems, a significant challenge associated with their implementation is the issue of nanoparticle deposition and sedimentation. Numerical analyses often neglect the deposition layer formed on the walls of pipes and channels. Disregarding this layer in simulations can lead to significant errors in estimating fluid flow and heat transfer parameters. This study investigates the boiling flow of four different nanofluids (nickel–water, gold–water, aluminum–water, and titanium oxide–water) with a volume fraction of 0.03% and pure water in a vertical tube with a diameter of 1.45 mm using a two-dimensional simulation in MATLAB software. In the simulation, five mass transfer mechanisms including evaporation, condensation, deposition, entrainment, and fluid entry into the sedimentary area are considered. To simulate the sedimentary layer, the rules of the porous media have been used. In addition, Brownian motion of particles and Kapitza resistance are also considered in the calculations. The primary objective is to demonstrate the impact of deposition layer simulation on the heat transfer coefficient (HTC) and critical heat flux (CHF) in various nanofluids. The results indicate that the deposition layer causes an average reduction of 31% in the HTC and 16% in the CHF. The findings emphasize the importance of incorporating deposition layer simulation in analyzing boiling nanofluids. Ignoring sediment phenomenon can result in substantial errors in predicting heat transfer and CHF, with significant implications for the design and optimization of nanofluid-based cooling systems. [ABSTRACT FROM AUTHOR]

Reactive transport modeling (RTM) is an emerging method used to address geological issues in diagenesis research. However, the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood. This paper presents a case study of the Eocene Qaidam Basin that combines RTM results with petrological and mineralogical evidence. The results show that the Eocene Xiaganchaigou Formation is characterized by mixed siliciclastic-carbonate-evaporite sedimentation in a semiclosed saline lacustrine environment. Periodic evaporation and salinization processes during the syngeneticpenecontemporaneous stage gave rise to the replacive genesis of dolomites and the cyclic enrichment of dolomite in the middle-upper parts of the meter-scale depositional sequences. The successive change in mineral paragenesis from terrigenous clastics to carbonates to evaporites was reconstructed using RTM simulations. Parametric uncertainty analyses further suggest that the evaporation intensity (brine salinity) and particle size of sediments (reactive surface area) were important rate-determining factors in the dolomitization, as shown by the relatively higher reaction rates under conditions of higher brine salinity and fine-grained sediments. Combining the simulation results with measured mineralogical and reservoir physical property data indicates that the preservation of original intergranular pores and the generation of porosity via replacive dolomitization were the major formation mechanisms of the distinctive lacustrine dolomite reservoirs (widespread submicron intercrystalline micropores) in the Eocene Qaidam Basin. The results confirm that RTM can be effectively used in geological studies, can provide a better general understanding of the dolomitizing fluid-rock interactions, and can shed light on the spatiotemporal evolution of mineralogy and porosity during dolomitization and the formation of lacustrine dolomite reservoirs. [ABSTRACT FROM AUTHOR]

A comprehensive study of the Maastrichtian–Danian boundary rocks in the Klementyev Mountain section (eastern Crimea) was carried out. The lithological characteristics of carbonate, carbonate–clayey, and clastic rocks are scrutinized. The dynamic of changes in the benthic and planktonic foraminiferal assemblages is analyzed. The geochemical and isotopic data were obtained for this section for the first time. The stratigraphic range of the upper Maastrichtian and lower Danian has been specified. The late Campanian–early Maastrichtian age of the underlying rocks has been confirmed for the first time. Sediments of the Klementyev Formation were deposited in a deep-sea pelagic paleoenvironment on the submerged part of the outer shelf, whereas the overlying Lower Danian sediments were deposited in shallow waters of the inner shelf with terrigenous sedimentation and high hydrodynamic activity. [ABSTRACT FROM AUTHOR]

The paper considers the composition of sandy rocks from the Upper Triassic deposits of the Mongugai Formation of southwestern Primorye and presents the results of its paleogeodynamic interpretation. It has been established that, according to their mineralogical and geochemical parameters, sandstones are petrogenic, correspond to graywackes and, only partially, to lithite arenites, are characterized by a significant degree of geochemical maturity of the clastic material, and their formation occurred due to the erosion of significantly weathered parent rocks of the source areas. Generalization and paleogeodynamic interpretation of the data obtained indicate that sedimentation in the southwestern Primorye in the Late Triassic occurred in basins related to the active continental margin settings probably complicated by strike-slip dislocations along transform faults. The dominant source of detrital material was continental land: cratons and crystalline basement inliers surrounding the rift zones or along transform faults. Felsic granite-metamorphic complexes were eroded with the participation of sedimentary rocks enriched with ancient components. A secondary source was a deeply dissected continental-margin igneous arc, which supplied an additional amount of sialic material, as well as a small amount of the basic–intermediate volcaniclastic rocks into the basin. The U–Pb geochronological studies of detrital zircons from sandy rocks of the formation made it possible to establish the age and the possible position of igneous complexes, destruction of which formed the sediments. [ABSTRACT FROM AUTHOR]

The main purpose of this article is to model an industrial spiral-type gravitational coalescer by applying population balance as the governing equation. In this model, considering the two-dimensional movement of crude oil flow in the coalescer, the mechanisms of differential sedimentation, laminar shear, and Brownian motion are considered to determine the collision rate of droplets. Then, the population balance equation was solved to determine the droplet size distribution, dehydration, and desalination efficiency using the class method. The simulation results were in good match with the gathered industrial data. Finally, the influence of interfacial tension of water and oil, the pressure drop of the mixing valve, oil temperature, oil density, and washing water flow rate on the process efficiency was analyzed. The modeling results indicated that increasing the interfacial tension of water and oil from 30 to 36 mN/m and the oil density from 800 to 900 kg/m3 will decrease the water removal efficiency by 4.35% and 14.18%, respectively. Also, increasing the temperature of oil from 300 to 340 K and the volume fraction of washing water from 3% to 15% improves the efficiency of separating water from crude oil by 9.55% and 9.95%, respectively. [ABSTRACT FROM AUTHOR]

Since the building roof acts as hub for atmospheric sediment deposition, the attached microbes can enter rainwater storage tank with ease to cause health issue for rainwater users. This study aims to explore the trend of roof-top deposited microbes in the different areas of Ikorodu local Government Area at Lagos, Nigeria. This paper also tests the hypothesis that the roof sediment deposition being a significant source to home bacteria. The total deposition rate on the roof for 34 weeks, which include 17 rainy and 17 dry weeks, were investigated. The enumerated bacteria was obtained from the roof deposit samples, where four representative different sites have been analysed to study the solid depositions and microbes within the area thoroughly. The sites were selected judging by their levels of sanitation and vegetation rate. The experimental investigations showed that enumerated microbes and total suspended solid (TSS) depositions in the different areas were higher in the dry season compared to rainy season, and the highest deposition was experienced in the Harmattan period. In addition, the results showed that areas with poor drainage infrastructure and poor sanitation have the roof-top deposition with higher bacterial count than good sanitation areas; while the unpaved and unvegetated areas produced higher deposits than the paved and vegetated areas. In terms of contamination sources, this study has illustrated that the particulate deposition on the roof-top prior to collection has further contaminated the roof-harvested rainwater. [ABSTRACT FROM AUTHOR]

Cobalt-rich ferromanganese crusts (CRC) are potential resources for Co, Ni, Pt, and other strategic metals. The CRC thickness varies from a few mm to more than 100 mm at various distance scales over the rock outcrops in the seamounts. However, their variation patterns and controlling factors are not well understood. We conducted a comprehensive small-scale survey, including shipboard acoustic measurements, seafloor observations, and rock drilling over the Xufu Guyot of the Marcus-Wake seamounts in the Northwestern Pacific to characterize the thickness variations on a scale of several kilometers with the topography and geological evolution of the guyot. Rock drilling revealed that thicker CRC (>100 mm) tend to occur on the margins and flat areas on the guyot, while thinner CRC are associated with carbonate reef mounds over the volcanic pinnacles and seamount slopes. The microstratigraphic description indicated that the CRC thickness is strongly related to the geological evolution of the guyot, mainly the stability of the substrate rocks and coverage with calcareous pelagic sedimentation. [ABSTRACT FROM AUTHOR]

The suspension of porous particles in fluids occurs widely in various natural and industrial processes. However, the sedimentation behavior of porous particles is not extensively understood as the solid impermeable counterparts. In this work, the drafting–kissing–tumbling (DKT) phenomenon in a narrow channel containing porous particles is investigated by the multi-relaxation-time (MRT) lattice Boltzmann method (LBM). The initial particle spacing L p * (1.5 ∼ 6) and Darcy number Da (8 × 10 − 6 ∼ 6 × 10 − 2 ) are examined on the sedimentation process of two particles under three initial arrangements, i.e., the trailing particle is porous (case 1), the leading particle is porous (case 2), and both the particles are porous (case 3). The results show that the presence of porous particles can enhance the interactions between two particles, and increasing the penetrability reduces the particle drag force to accelerate sedimentation. The drafting time is insensitive to Da at small L p * , and it decreases with Da at large L p * in cases 1 and 3 while it changes to increase with Da in case 2. A phase diagram with respect to Da and L p * is further extracted to identify three sedimentation modes of particle pairs. It is found that the transition between the one-off DKT and repeated DKT modes is not affected by L p * in cases 2 and 3, while the critical condition for the non-DKT and one-off DKT modes depends strongly on Da and L p * in case 2. [ABSTRACT FROM AUTHOR]

Mineralogical and geochemical studies have been undertaken on the Triassic to Lower Jurassic Adigrat Sandstone of the Blue Nile Basin of central Ethiopia to infer its source rock type, paleoweathering, and paleoclimatic history. The Adigrat Sandstone occurs at the basal section of the Mesozoic sedimentary formation and unconformably overlays the Neoproterozoic–Paleozoic crystalline rocks, or locally, the Karroo sediments in the northern Blue Nile Basin. A mineralogical study reveals that quartz (Q), feldspars (F), and lithic fragments (L) are the framework grains of the sandstone. On the QFL diagram, the plot of the modal composition of the sandstone mainly falls within the feldspathic arenite and quartzose arenite fields. The geochemical data of the lower section of the sandstone mainly falls within the arkose and subarkose fields, whereas the upper section data falls within the quartzose and sublithic arenite fields. Mineralogical and geochemical weathering indices indicate that the provenances of the Adigrat Sandstone were exposed to pronounced weathering intensity, where the lower part of the sandstone was controlled by arid to semi‐arid conditions, whereas the upper section was linked to humid to semi‐humid (tropical to subtropical) climatic conditions. Mineralogical and geochemical data also indicate that mafic to intermediate basement rocks were the primary source rocks of the sediment. Perhaps the sediment was assumed to have been reworked by multi‐cyclic sedimentary processes. The discriminant function diagram, the REE pattern, La/Th vs. La/Yb, and the Th–Hf–Co plot are consistent. A comparison of provenance studies for the Adigrat Sandstone in the Blue Nile Basin and the Mekele outlier of northern Ethiopia indicates that the sediment of the former is highly sorted, experienced higher weathering intensity, and compositionally derived from mafic to intermediate crystalline rocks. On the other hand, the sediment of the latter is essentially a weathering product of felsic rocks. [ABSTRACT FROM AUTHOR]