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Shangshan is the earliest Neolithic culture discovered in the lower Yangtze region and is significant as one of the origins of rice agriculture worldwide. During the Early Holocene, the Shangshan human groups settled in the river basins of the upper Qiantang region and transitioned from hunter-gatherers to farmers. Little is known about the dominant factors motivating them to settle down and their occupation patterns for adapting to local environments. To address these issues, we applied an ad hoc method by coupling landform classification, geomorphic fieldwork, accessibility analysis, and flood risk assessment. The results of geomorphic and accessibility analyses show that the ancient residents preferred to occupy the edges of the Middle Pleistocene terraces along second- and third-order streams. These locations are mainly situated in the centers of river basins and have height differences of 5–15 m, less than approximately 15-min walking distance from streams, providing them with stable residential spaces and accessible water resources. Within the 10-min territorial scope, there are always some fluvial plains near the terrace edges, indicating that the plain is another critical landform utilized by the residents. The wide plains and a plain-terrace-upland geomorphic assemblage, within 1-h and 2-h scopes, respectively, imply that the residents started to develop agricultural land while they also exploited diverse environments to ensure a plentiful food supply. Furthermore, the hydrologic analysis and assessment reveal that the residents were aware of the potential flood risks: their settlements are located at 30-min walking distance or greater from the high-order streams; most sites are exposed to low flood risks, with average percentages of unflooded territory greater than 67% and 43% in the minor and large flood scenarios, respectively; and each site has sufficient arable land with areas of 5–23 km2 within a 1-h scope, even under the large flood scenario. Overall, these results reveal that the river basins provided favorable living environments, and the residents could flexibly manage the landscapes to ensure stable settlements and food production, thus enabling the appearance and development of a sedentary society and rice agriculture during the early Holocene. Ultimately, the methods used in this study provide an effective approach to exploring the occupation patterns of prehistoric residents in the river basins. [ABSTRACT FROM AUTHOR]

The transition from syn‐rift to post‐rift sedimentation in rift basins is difficult to characterize in terms of stratigraphic architecture and dominating control on sedimentation, due to decreasing tectonic activity interplaying with regional subsidence, eustatic sea level changes, and differential compaction of underlying syn‐rift sediments. Our case study of the Late Palaeozoic Inner Hornsund Fault Zone targets late syn‐rift strata recorded in the (?Pennsylvanian – ?lower Permian) Treskelodden Formation in Hornsund, southern Spitsbergen, representing a mixed siliciclastic‐carbonate succession, with siliciclastics primarily sourced from the adjacent Sørkapp‐Hornsund High. We document local scale (<10 km) facies variability, sequence stratigraphy, and evolution of a succession deposited along a flank of the structural high during the late syn‐rift stage. We observe that during the transition towards rift termination (glacio‐)eustatic sea level changes and overall regional flooding became a more prominent forcing factor controlling sedimentation. Our dataset includes sedimentary logs, microfacies analysis, and high‐resolution digital outcrop models. We identify four progressively backstepping stratigraphic sequences, reflecting an evolution from (1) terrestrial siliciclastics through (2–3) nearshore mixed siliciclastic–carbonates, to (4) carbonate ramp deposits. On the small scale (<5 m) the internal sediment cyclicity of the succession was formed by autogenic processes, particularly the changing rate of sediment input from the southwestern source area (the uplifted Sørkapp‐Hornsund basement high). On the larger scale (10s of m), the importance of glacio‐eustatic sea‐level changes, driven by waxing and waning of ice caps in the southern hemisphere (Gondwana), increased as the rift‐related tectonics decreased. The interdisciplinary methods used in this study provide new knowledge of the Middle Pennsylvanian to Permian depositional evolution in southern Spitsbergen, besides a novel framework for comparison to adjacent basins in the region and similar basins elsewhere. [ABSTRACT FROM AUTHOR]

Aquatic ecosystems are often impacted by a multitude of stressors, many of which are introduced by a combination of anthropogenic activities such as agricultural development, urbanization, damming, and industrial discharge. Determining the primary stressors responsible for ecological impairments at a site can be complex and challenging; however, it is crucial for making informed management decisions. Improper diagnosis of an impaired system can lead to misguided attempts at remediation, which can be both time consuming and costly. We focused on the development, implementation, and evaluation of methodologies that, in combination, allowed us to identify the primary stressors. These included a four‐phase, weight‐of‐evidence (WOE) assessment including in situ Toxicity Identification and Evaluation (iTIE) testing, physicochemical and macrobenthos characterization, reciprocal sediment transplants, and laboratory and in situ toxicity testing. The contaminants of concern (COCs) at the site were elevated levels of ammonia, chloride, pH, and total dissolved solids in groundwater upwellings into a high‐quality waterway. Reciprocal transplants of site sediments and nearby reference sediments and traditional benthic sampling showed impaired benthic indices and multiple stations around a contaminated industrial settling basin. Impaired stations had elevated COCs in groundwaters but exhibited a steep vertical concentration gradient, with concentrations decreasing near the sediment–surface water interface. We describe Phase 4 of the study, which focused on teasing out the role of dissolved oxygen sags in benthic macroinvertebrate responses. Extensive submerged and emergent macrophytes, algae, and cyanobacteria co‐occurred at the impaired sites and increased throughout the summer. Laboratory testing suggested that ammonia and pH were possibly toxic at the sites, based on groundwater concentrations. The in situ toxicity testing, however, showed toxicity occurring even at stations with low levels of COCs concurrently with large diurnal fluxes in dissolved oxygen (DO). A final phase using a type of iTIE approach utilized limnocorrals with and without aeration and with in situ toxicity measures using Hyalella azteca. The Phase 4 assessment revealed that low DO levels were primarily responsible for impaired benthic communities, and COC upwellings were diluted at the sediment–water interface to nontoxic levels. These findings will allow for improved management decisions for more efficient and effective restoration activities. Environ Toxicol Chem 2024;43:1524–1536. © 2024 SETAC [ABSTRACT FROM AUTHOR]

Polymetamorphic metapelitic rocks in central‐west Tasmania, southern Australia, contain high‐pressure mineral assemblages that formed during Cambrian‐aged subduction and relict garnet with published Lu–Hf ages of c. 1285–1240 Ma. These garnet ages, along with published detrital zircon data from throughout western Tasmania and western North America, have been used to propose the presence of Mesoproterozoic Laurentian crust in western Tasmania. In this study, we combine zircon petrochronology with compositional information from the inclusion assemblages in relict garnet to extract Mesoproterozoic pressure–temperature data from subduction‐overprinted rocks, which effectively constitute an interpreted remnant of Laurentian crust now residing in central‐west Tasmania. The new data suggest Mesoproterozoic metamorphism involved two stages. The first event is recorded by c. 1480–1235 Ma zircon that formed in a garnet‐absent, plagioclase‐present, high‐thermal gradient environment at pressures no greater than ~5–5.5 kbar. The second event recorded by c. 1285–1240 Ma relict garnet was characterized by the development of a moderate‐pressure kyanite–plagioclase–biotite‐bearing mineral assemblage, which formed at ~8.5 kbar and ~590–680°C. These pressure–temperature constraints are attributed to extension within a deep basin system associated with the cryptic East Kootenay Orogeny in North America, which coincides with the final stages of c. 1450–1370 Ma upper Belt‐Purcell Basin sedimentation. Taking into account new detrital zircon U–Pb–Hf isotopic data from central‐west Tasmania in this study and existing zircon provenance data from throughout western Tasmania and the Belt‐Purcell Basin, our results strengthen the hypothesis of a Laurentian footprint that potentially encompasses much of western Tasmania and relates to both Nuna and Rodinian tectonism. [ABSTRACT FROM AUTHOR]

Sedimentary basins are valuable archives of tectonic processes involved in continental rifting. The northern Rocky Mountains preserve the Belt Supergroup, one of the most complete records of Mesoproterozoic strata on Earth; however, debate remains about its tectonic origin. We investigated a recently identified package of Mesoproterozoic strata at Leaton Gulch near Challis, Idaho, using a combination of traditional and newer sedimentological tools. Results suggest that the Leaton Gulch stratigraphic section was deposited in a fluvial setting ca. 1,380–1,317 Ma, spanning the poorly documented interval between late Belt Supergroup deposition at ∼1,370 Ma and recently characterized Deer Trail Group strata that are less than 1,300 Ma. Detrital zircon age distributions from Leaton Gulch demonstrate a similar provenance signature to Missoula Group rocks of the upper Belt Supergroup; however, Leaton Gulch strata are up to ∼70 Ma younger than most prior age constraints on Belt Supergroup rocks. Regional metabentonites (interpreted as metamorphosed reworked tuffs) found within Leaton Gulch and Missoula Group strata show dominantly radiogenic εHf(t), with a range of −8 to +15, interpreted as a mix of primary mantle and remelted metasedimentary sources. Zircon trace element data of the metabentonite from Leaton Gulch suggest a 1,450–1,300 Ma geochemically consistent and moderate–high silica melt source. Collectively, the strata of Leaton Gulch record basin sedimentation during a critical window of Mesoproterozoic time. We speculate that sedimentation during late‐stage Belt Supergroup deposition thickened and stepped westward, abandoning the main Belt basin, culminating with breakup of the Nuna Supercontinent. Plain Language Summary: Sedimentary basins serve as important records of continental breakup. One of the most complete basin records in North America is the 1470–1370 million year old Belt Supergroup, but its tectonic origin is still poorly understood. We investigated recently identified Mesoproterozoic sedimentary rocks near Challis, Idaho. By measuring the sedimentary rocks and determining the age and chemistry of detrital (transported as ancient sediments) zircons within them, we conclude that the rocks at Leaton Gulch were deposited in a river setting between 1380 and 1317 million years ago. Leaton Gulch rocks therefore span a poorly documented interval between the Belt Supergroup and younger (∼1,300 Ma) Mesoproterozoic rocks of the Deer Trail Group preserved in eastern Washington. Detrital zircons from Leaton Gulch rocks record a sediment provenance similar to that of upper Belt Supergroup rocks. Regionally distributed metabentonites (ancient volcanic ash), found both at Leaton Gulch and in Belt Supergroup rocks, have chemical signatures consistent with continental rifting. Leaton Gulch rocks therefore record the sedimentation and rifting after deposition of the Belt Supergroup predicted by paleogeographic reconstructions. Late‐stage Belt Supergroup rocks thickened and stepped westward through time, ultimately abandoning the main Belt basin, culminating with the breakup of one of Earth's earliest supercontinents, Nuna. Key Points: Fluvial deposition occurred <1,380–1,317 Ma between Belt Supergroup deposition and late‐stage breakup of the Nuna supercontinentLeaton Gulch strata record continued sediment sourcing from the Belt Supergroup or local recycling of Belt Supergroup sedimentary rocksTiming of deposition and detrital zircon results are consistent with westward stepping of rifting after deposition of the Belt Supergroup [ABSTRACT FROM AUTHOR]

Sedimentary basins adjacent to subduction‐related continental arcs provide important archives for deciphering the intricate history of convergent plate margins. The east‐west trending Gangdese magmatic arc was one of the most predominant topographic features located at the southern margin of Tibet before the arrival of the Indian plate. However, the detailed Cretaceous growth and evolution across the arc system remains ambiguous. Stratigraphy of the adjacent Xigaze forearc basin provides a well‐preserved and well‐exposed record of the tectonic and magmatic evolution of the arc throughout the Cretaceous period. We report new stratigraphic, sedimentological, geochronological, and provenance analyses of the Quarry Ridge sandstone in the Xigaze forearc basin along with compiled zircon U‐Pb ages (n = 9674) and Lu‐Hf isotopic signatures (n = 3389) from the Gangdese arc, the Xigaze forearc basin, and the Linzhou retroarc foreland basin to reconstruct the Early to middle Cretaceous magmatism and uplift of the Gangdese arc and concurrent sedimentary responses within both basins. Exhumation of the arc initiates at around 113 Ma suggested by arc detritus first arriving in both basins. Another episode of inferred uplift occurs at around 108 Ma, which resulted in coarse‐grained sedimentation in adjacent basins, preventing Central Lhasa detritus from reaching the Xigaze forearc basin further south and a facies and provenance change within the Linzhou basin. Finally, a third episode at around 101 Ma is reflected by deposition of the progradational Quarry Ridge clastic succession and marks the initiation of a substantial coarse‐grained depositional stage in the Xigaze forearc basin. Our study emphasizes the connection between coarse‐grained deposition in the forearc basin and arc magmatism and uplift. This study also provides an orogen‐scale assessment of the history of arc magmatism, uplift, and sedimentation across the Gangdese magmatic arc system, which supports interpretations that Tibet was already characterized by complex and substantial topographic relief during the Cretaceous before the collision between the Indian and Eurasian plates. [ABSTRACT FROM AUTHOR]

Introduction: The study of erosion and sedimentation is a crucial aspect and an integral part of watershed studies in a basin. The methods employed to prevent erosion and sedimentation play a significant role in basin management planning. However, due to the lack of accurate statistics on erosion and sediment amounts, it becomes necessary to utilize estimation models for assessing erosion and sedimentation. These models are often region-specific and may have a wide range of uncertainty in different areas. One notable benefit of modeling, regardless of its type, is its ability to analyze natural processes within the basin. On the other hand, understanding erosion and sedimentation processes in a region can be an effective step in managing, planning, and prioritizing available resources. In this research, the aim was to determine the sensitivity of the MPSIAC model to the relationships among its parameters. Additionally, the goal was to assess the model's sensitivity to changes in these parameters and their impact on sedimentation. By identifying the influential ground and atmospheric parameters, it becomes possible to prioritize their effect on water sedimentation in the region. Materials and methods: Through the sensitivity analysis of the model, it is possible to identify the flexibility of the model to the changes of its various parameters. It is also possible to determine the relationships between model variables and prioritize the parameters affecting the model output. Sensitivity analysis can be used in the calibration stage, in such a way that results are accurate, and time and cost are saved. In this study, to analyze the sensitivity of the MPSIAC model, first, the nine parameters of the model were examined. Then, according to the arrangement of different parameters in the structure of this model, the parameters were numbered from X1 to X9. Then, the score range of each parameter was entered in its calculation table according to the modified model of PSIAC. In this step, the average of each parameter was calculated according to its upper and lower limits. To achieve this, the nine parameters of the model were standardized, and the sedimentation rate was estimated by varying each parameter within its lower and upper limits while keeping the other parameter(s) fixed at their averages. With each change, the sediment discharge was calculated. Results and Discussion: In the analysis of the results, the slope of the curves of the standardized parameters relative to the dependent variable (specific sediment) is considered. So that, any part of the curve that has more slope changes means that the model is more sensitive to minor changes in that parameter in that interval. In this study, the results of this sensitivity analysis reveal that the slope factor and runoff volume have a considerable influence on sediment yield. For slopes up to approximately 15%, the slope parameter has a relatively smaller impact compared to other parameters. However, as the slope value increases, its effect becomes more pronounced, indicating that high slopes (greater than 15%) have the greatest impact on sedimentation. The runoff factor exhibits a sudden increase in sensitivity at higher flow rates. Conclusion: In examining the effect of different parameters on the model performance, the parameters that had the largest slope of changes can be considered as the most effective parameters in sedimentation of the basin. In other words, the model demonstrates high sensitivity to slight changes in specific peak discharge values above 20 m³/s/km². Therefore, implementing integrated (biomechanical) management measures to control slope steepness and reduce runoff volume can be an effective strategy for mitigating sedimentation. Therefore, based on the results, the role of land factors is very important, such as slope and then runoff, in the erodibility and sediment production in basins. Of course, it should be noted that climatic parameters directly and indirectly affect the amount of peak flood discharge and should not be neglected for their importance and influence in flooding and subsequently the erodibility of the watershed. [ABSTRACT FROM AUTHOR]

During the re-mapping of the area for the Geological Atlas of Switzerland, a significant stratigraphic unconformity was discovered in the North Penninic (Valais) Bündnerschiefer and the Flysch series of the northern Prättigau. It separates different units of the Cretaceous Bündnerschiefer from the Palaeogene Flysch. We explain this observation by a basin conversion from extension to compression, which caused the initial deformation of the Bündnerschiefer in an accretionary wedge. Interlinked return-flow has created a new heterogeneous substrate for the flysch sediments and explains the different types of unconformities. The basin conversion coincided with high-grade metamorphism in the vicinity of the the South Penninic suture and the Austroalpine units, and the increased exhumation in the Austroalpine nappe stack. Detrital zircon dating confirms also a change from European to Austroalpine detrital sources in the flysch sandstones. We discuss a palaeotectonic model leading to hP/lT metamorphism of the Bündnerschiefer in the Late Eocene (c. 42 Ma). It appears that the flysch formations were also involved, but to a lesser degree by tectonic deformation from the late Early Eocene onwards, as the pervasive folding characteristic of the Bündnerschiefer is absent. This has been followed by a phase of S-directed backfolding. During the Oligocene and Miocene, more extensive deformation occurred by SE to NW compression and finally by probable westward thrusting and folding. Our main theme is the transition from passive to active continental margins, which in Alpine plate tectonic framework corresponds to the transition to flysch sedimentation by basin conversion. Our results show that the simultaneity of the transition from extension to compression, as indicated by the accumulation of flysch, shifted in time from south to north in the Alpine Tethys. [ABSTRACT FROM AUTHOR]

The impact of tectonics, volcanism and climate in controlling temporal and spatial variations in rift‐basin sedimentation is still poorly understood. Here, we tackle this issue by the analysis of mid‐Cretaceous sediments deposited in the Songliao Basin, northeastern China. We present new zircon U–Pb, apatite fission‐track and trace‐element data from the northeastern basin, which are discussed within the framework of the published geochronology dataset. Our results reveal a major provenance change from syn‐rift tectonic extension to post‐rift thermal subsidence at ~103 Ma. During the syn‐rift stage, the detrital inputs were dominantly from transverse rivers sourced from the surrounding mountains including graben shoulders and volcanoes. During the post‐rift stage and coeval thermal subsidence, the basin sedimentation was controlled by coexisting transverse and axial drainage systems sourced from uplifting regions in the south. We conclude that tectonics, not climate, exerted a major control in sediment provenance change in the mid‐Cretaceous Songliao Basin. [ABSTRACT FROM AUTHOR]

There has been no consensus yet regarding the precise initial timing and duration of the late Mesozoic extensional tectonics in the South‐eastern China Block. This work focusses on the growth strata of the Early Cretaceous red beds in the South‐eastern China Block to determine the late Mesozoic tectonics and the precise timing of the initiation and duration of extensional tectonics in this area. Field observation of several terrigenous basins shows that the dip angles of the Cretaceous red beds have varied from moderate to gentle from basin edges to interiors (or centres). The visible and estimated thickness within a single bed increases slightly downwards from the upper to the lower part. These characteristics indicate that the sedimentary area of these beds has undergone an extensional process with expansion and deepening of the sedimentary basins. Rotation of the border surfaces (limbs) and downward warping of the hanging walls or retreat of the footwalls of listric normal faults causes three types of extensional growth (or syntectonic) strata in the deposits of different basins. Dating of the volcanic rocks related to the growth beds reveals that the sedimentary basins were enlarged and deepened when the Early Cretaceous strata were deposited in the South‐eastern China Block from ca 140 to 137 Ma. Regionally, under the influence of Palaeo‐Pacific plate rollback since ca 140 Ma, the South‐eastern China Block stress field has led to lithospheric uplift and pull‐apart structures near the surface, causing the half‐graben basins to receive sedimentation. Although the extensional event was interrupted by a short compressional event during 120 to 105 Ma, with the oceanward retreat of the trench, the area of extension gradually enlarged and rejuvenated south‐eastwards until the end of the Cretaceous. This Cretaceous extension event of the South‐eastern China Block must belong to a worldwide geological event with global significance. [ABSTRACT FROM AUTHOR]

Growth of the Tibetan Plateau, Earth's broadest and highest elevation collisional system, shapes orographic barriers, reorganizes drainage networks, and influences surface erosion and sediment delivery, whose changes in space and provenance feed back to intracontinental tectonic processes. Studies of interior basins within the northern Tibetan Plateau provide new sediment accumulation, provenance, paleodrainage, and deformation timing data that enable a reconstruction of the far-field tectono-geomorphic evolution of the rising Tibetan Plateau. Along the northern plateau margin, topographic growth in the West Qinling Belt is inferred to have initiated in the Eocene, nearly coeval with the India-Asia collision, as well as in the late Miocene. However, geological knowledge about the intervening period remains at present enigmatic, and the kinematics and dynamics are uncertain. This study presents a multidisciplinary data set from the intermontane Anhua-Huicheng Basin (AHB; Gansu Province, China) to fill this gap. Magnetostratigraphic dating, regional mapping, and sedimentological analysis imply that contractional deformation and thrust-top basin systems formed within the West Qinling Belt in the Oligocene (not later than ca. 24 Ma). A combination of observations including paleocurrent changes, detrital zircon U-Pb age variations, and appearance of growth strata along the Anhua-Huicheng Basin reveal the rapid uplift of the West Qinling Belt at ca. 15 Ma. Sedimentation in the intermontane basins ended after the late Miocene (ca. 8 Ma), when the region experienced intrabasinal deformation, uplift, and erosion with the establishment of an external drainage system. Since the late Miocene, the growth of the West Qinling Belt reached a climax with the lack of substantial contractional deformation in Cenozoic sequences heralding the onset of the modern kinematic regime and attainment of high elevation. Observed transitions in the tectonostratigraphy and paleodrainage define different phases of deformation and plateau-wide shifts in stress reorganization, which led to the northward growth and later lateral expansion of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Terrestrial organic matter (OM) plays a key role in coastal organic carbon burial. However, few studies focus on the relationship between land use in the watershed and the transport of terrestrial OM to coasts from a long‐term perspective. In this study, we compared terrestrial OM deposition between an inlet of the Baltic Sea and an upstream lake within the same watershed over the last 500 years, using lignin biomarkers in the sediments. In combination with pollen‐based quantitative land cover reconstruction, we assessed the impacts of semicentennial‐scale changes in land use on terrestrial OM export. The results indicated that the concentration, composition, and degradation state of the lignin‐derived OM differed substantially between the two sites. The lake received larger amounts of lignin‐derived OM during periods of intensified agriculture, but the coastal site did not. The composition of lignin in the coastal sediment did not directly reflect variations in vegetation cover in the watershed. The reason could be that the OM was settled in the upstream basins. Furthermore, the terrestrial OM that did reach the coastal sediments was modified through degradation during the transport, and only the refractory component was deposited at the coast in a relatively unaltered form. Plain Language Summary: Agriculture and deforestation have a considerable impact on the global carbon cycle by increasing soil erosion and organic matter (OM) deposition in water bodies, and the transfer of carbon from the terrestrial to the aquatic system works as a carbon sink. The amount, type of OM and degradation during the transport determine how effective this transfer is. In this study, we used sediment cores from an inlet of the Baltic Sea (Gåsfjärden) and an upstream lake (Storsjön) in southern Sweden to investigate the link between land‐use changes and OM matter transport and deposition since CE 1550. We reconstructed terrestrial OM deposition using lignin phenols, which are almost exclusively produced by higher plants, and land use in the catchment using pollen analysis. The results suggest that farmland expansion caused increased terrestrial OM export to the lake but not at the coastal site, and the terrestrial OM composition at the coast was not significantly affected by the vegetation changes. The reason could be that fraction of the OM from upstream was altered or settled down before reaching the sea. Our findings contribute to a better understanding of the impacts of long‐term land‐use dynamics on the global carbon cycle. Key Points: Integration of lignin phenols and pollen‐based land‐cover reconstruction in sediment cores from both the coast and an upstream lakeDuring intensified agriculture, the deposition of terrestrial organic matter (OM) increased in the lake, but not in the coastal zoneComposition of deposited terrestrial OM varied in the lake responding to vegetation changes on catchment but not at the coast [ABSTRACT FROM AUTHOR]

Fars sub-basin is located in the Zagros fold-thrust belt and includes a large number of hydrocarbon reserves, especially gas. The existence of numerous basement faults and strike-slip in this region along with the uplift and depocenter of basement blocks has been considered effective factors in controlling sedimentary basins before, after, and synchronous with sedimentation. In this study, the role of the Razak fault basin in the external Fars area as an effective factor in controlling the sedimentary basin was evaluated. For this purpose, by providing isopach maps and 3D modeling from the basin floor at synsedimentary formations, the activity of the Razak fault along with its role in increasing or decreasing the hydrocarbon potential of the region and adjacent anticlines, was investigated. The results show that the inactivity of this fault at the sedimentation time of the Dalan, Gadvan, Darian, and Kazhdumi formations, while at the deposition time, the formations of Kangan, Dashtak, Hith, Fahlian, Laffan, Ilam, and Pabadeh remained active and controlled the sedimentation in the basin. Also, the uplift and depocenter of the basement blocks occurred to the Razak fault's performance, caused an increase in the hydrocarbon potential of the Dehram Group in the anticlines of Marz, Varavi, Tabnak, Dehnow, Khalfani, Chiru, and Madar. While the northeastern part of the study area and the anticlines of Bonashkatu, Pishvar, Bavush, Gavbast, and Gezzeh are less important. In addition, Khami and Bangestan reservoirs are also without hydrocarbon potential due to the Razak fault's performance. [ABSTRACT FROM AUTHOR]

The Late Pliocene Gilbert-type delta is described in the western Erzurum Basin (NE Turkiye) and its position in the Late Cenozoic development of the basin is defined. The Erzurum Basin originated no later than Late Miocene between two Mesozoic ophiolite zones, continuing the Izmir–Ankara–Erzincan suture. In the Late Miocene–Pliocene, the basin was filled with fine-grained clastic and carbonate sediments of lacustrine-lagoon type. The Gilbert-type delta formed at the top of these deposits in the western part of the basin. The delta consists of 11 wedge-shaped bodies of clay, silt, sand, and gravel that were deposited as foresets of different phases of the delta development. The foreset bodies are dipping at 5° to 35° E. Some bodies underwent soft sediment deformation. The delta deposits are dated to Late Pliocene based on remains of small mammals and molluscs, palynological, and magneto-stratigraphic analysis. The delta eroded surface is overlain by alluvial pebbles dated to Early Pleistocene by archaeological finds. The Erzurum Basin is the westernmost member in a row of intermontane basins that continues to the east with the Pasinler, Horasan, and Agri basins that are drained by the Araxes River and its tributaries. It is likely that the paleo-Araxes River spread to the west in Late Pliocene and the studied delta was formed by its upper reaches that flowed into the water body of the Erzurum Basin. The delta deposits were covered by coarse alluvium in Early Pleistocene when the Erzurum Basin was tectonically isolated from the Araxes drainage system. In the latest Early Pleistocene or early Middle Pleistocene, the paleo-Araxes upper reaches were captured by the Euphrates River upper reaches that drain the Erzurum Basin now. The Upper Miocene and Pliocene deposits of the Erzurum, Pasinler, and Horasan Basins are similar and were accumulated in a single basin of sedimentation. Therefore, it can be assumed that the deposits of the upper Pliocene, containing the Akchagylian marine biota in the Horasan Basin, extended into the Erzurum Basin. However, the assumption that the upper reaches of the Euphrates River and the Erzurum Basin were the channel, through which the open sea biota entered the Akchagylian basin, is very unlikely for two reasons. Firstly, the Erzurum basin was limited by the described delta of the river, which flowed into it from the west. Secondly, the upper reaches of the Euphrates penetrated into the Erzurum Basin after the completion of the Akchagylian stage of sedimentation. [ABSTRACT FROM AUTHOR]

A comparative analysis of the morphological features of horizons affected by paleoearthquakes revealed significant difference of seismites from lithologically different deposits. Powerful earthquakes determine not only the destruction of the sedimentary structure of near-surface deposits and their chaotic mixing, but also actively affect the underlying layers to a depth of several tens of meters; since the degree of diagenetic lithification of rocks in different horizons varies with depth, the nature of their seismogenic transformations also changes. It was found that major seismic events were associated with the time intervals of tectonic and paleogeographic restructuring of sedimentation basins, which consisted in the intensification of the basin floor subsidence and changes in the composition of sediments accumulated in the paleobasin. A special type of seismites was formed during the impact of earthquakes on siliceous deposits, which have been spanned by the diagenetic redistribution of authigenic mineral matter in a gel state. [ABSTRACT FROM AUTHOR]

The researched area is located in Rembang Zone, North East Java Basin. The Rembang Zone is one of the largest basins in Indonesia. In this area, there are many oil wells that today are still actively producing. The research concerning the content of microfossils in marine sedimentary outcrops is needed to determine the rate of sedimentation in a basin. The method is basically based on the result of stratigraphic measurements of two sections with a distance of 2,743.7 m. Sedimentation rate is the average thickness ratio to the average time interval. The sections have a good outcrop and a continuous stratigraphic sequence from Miocene (Wonocolo, Ledok, and Mundu Formations) to Pleistocene (Lidah Formation). Samples taken in the section consisted of fourty-one samples of marls and shales. The results of the analysis show eighteen genera with fifty-seven species of nannoplankton. While the resulting biostratigraphic zone can be arranged into eleven zones consisted of two partial, one range and eight interval zones. The development of sedimentation rate (RoS) of studied area consists of ten periods, those are (1) CNM15 Zone/Late Miocene of Ledok Formation at a depth of 427.8 - 322.4 m, and has a sedimentation rate (RoS) of 11.46 cm/ky, (2) CNM16-CNM20 Zone/Late Miocene to Early Pliocene, Ledok Formation at a depth of 322.4 - 279.3 m and has a RoS of 1.54 cm/ky, (3) Mundu Formation is CNPL2 Zone/Early Pliocene at a depth of 279.3 - 223 m and has a RoS of 5.41 cm/ky, (4) CNPL3 (Early Pliocene) Zone at a depth of 223 - 148.4 m and has a RoS of 33.91 cm/ky, (5) CNPL4 Zone (Middle Pliocene) at a depth of 148.4 - 82.7 m and has a RoS of 5.09 cm/ky. (6) Zone of CNPL5 (Middle-Late Pliocene) at a depth of 82.70 - 53.1 m and has a RoS of 21.14 cm/ky, (7) CNPL6 Zone/Late Pliocene at a depth of 53.1 - 52.0 m and has a RoS of 0.24 cm/ky, 8). CNPL7 Zone/Late Pliocene to Early Pleistocene at a depth of 52.0 - 33.8 m and has a RoS 8.27 cm/ky, (9). CNPL8 Zone (Early Pleistocene) at a depth of 33.8 - 26.4 m and has a RoS of 1.14 cm/ky, (10) CNPL9 Zone? (Early Pleistocene) at a depth of 26.4 - 12.5 m and has a RoS of 1.7 cm/ky. The relatively faster sedimentation rate of the CNPL3 is due to the faster subsidence and maximum sediment supply. During the development of sedimentation rate, there are two unconformities, namely (1) after the CNM20 Zone resulting in a sedimentation interval during CNPL1 and (2) after CNPL6 (Late Pliocene). [ABSTRACT FROM AUTHOR]

Basin inversion is a process that takes place when a sedimentary basin is subjected to compressional stresses resulting in the reactivation of pre-existing faults and/or the localization of deformation along new reverse faults. The Araripe Basin (NE Brazil) is an example of a Cretaceous intracontinental aborted rift, with its sedimentary infill found at ca. 1000 m altitude, 500 m above the host basement. Post-rift basin inversion has been proposed by previous authors as the cause of this topographic high, but how inversion affected this basin remains a matter of debate, with the following two end-member scenarios: reactivation of pre-existing normal faults leading to local uplift or regional uplift and differential erosion. Neither end-member fully explains the observations from seismic and field data. In this study, we, therefore, conducted analogue models to explore how basin inversion in the Araripe Basin could have taken place. We present two series of crustal-scale brittle–viscous experiments: (i) extension followed by compression without sedimentation, with a variation in divergence and convergence directions (orthogonal or 45 ∘ oblique); and (ii) extension with syn-rift sedimentation followed by compression, with the same variation in rifting and inversion directions. We found that orthogonal rifting without sedimentation forms throughgoing graben boundary faults, whereas oblique rifting initially creates en échelon faults that eventually link up, creating large graben boundary faults. Rift basins with syn-rift sedimentation evolved in a similar fashion; however, sedimentary loading resulted in increased subsidence. During both oblique and orthogonal inversion, most shortening was accommodated along new low-angle reverse faults. Significant intra-graben fault reactivation occurred in all models without syn-rift sedimentation. By contrast, orthogonal inversion of models with syn-rift sedimentation did not reactivate rift faults, whereas only a minor reactivation of rift faults took place during oblique inversion since the sediments strengthened the otherwise weakened basin, thus acting as a buffer during convergence. Based on our modelling results, we propose an alternative scenario for the evolution of the Araripe Basin, involving oblique inversion and the development of low-angle reverse faults, which better fits observations from seismic lines and field data from the region. [ABSTRACT FROM AUTHOR]

Porosity estimation is essential for the exploration of hydrocarbons in sedimentary basins, which are affected by several factors such as the burial depth, lithology changes, sedimentary environment and diagenetic degree. Hence, detailed understanding of reservoir porosity is essential for estimating potential economic reserves and developing an explored hydrocarbon field. The present study uses high‐quality three‐dimensional (3D) seismic reflection data to decipher the porous zones within the Eocene‐Oligocene‐Miocene intervals of the Upper Assam Basin. The coherency seismic attribute has brought out several fault‐bounded structures that control the reservoir geometry. Random forest‐based machine learning technique has been utilized for the porosity estimation within the formations of interest. It is observed that the north‐east (NE) parts of the targeted intervals are porous with varying porosity of 0.28–0.42. The Miocene period witnessed a high amount of sedimentation within the basin. Different structural highs and thicknesses are pronounced in the NE part of the study region. Thus, the Miocene intervals are favourable leads for the exploitation of hydrocarbons. [ABSTRACT FROM AUTHOR]

The mass extinction at the Cretaceous–Palaeogene boundary is widely attributed to sudden and severe climate changes forced by bolide impact and/or flood basalt volcanism. In terrestrial depositional settings, these changes may potentially be recorded by palaeosols. To test the ability of pedogenic features to record both long‐term climate and shorter‐term changes preceding and following the Cretaceous–Palaeogene extinction event, palaeosols in the Upper Cretaceous (Maastrichtian) Naashoibito Member of the Ojo Alamo Formation and the lower Palaeocene (Danian) Nacimiento Formation in the San Juan Basin of north‐western New Mexico, USA, were examined, including data from previous studies. The fine‐grained facies of the Naashoibito Member comprises grey to greenish‐grey and red‐banded mudstones displaying pedogenic features including colour mottling, root traces, cutans, ped fabrics, pedogenic slickensides and calcareous nodules. Aside from a high‐chroma horizon at the formation base, palaeosols in the lower Nacimiento Formation are broadly similar to those observed in the Naashoibito Member. Lateral and vertical variability of the pedogenic features between correlated sections suggest that soil hydrology varied spatially and temporally from very saturated to seasonally well‐drained, with temporal variations controlled by basin sedimentation rates. Abrupt and/or catastrophic climate events precisely at the Cretaceous–Palaeogene boundary are not recorded due to an unconformity at the top of the Naashoibito Member. However, the presence of kaolinite in the clay mineral assemblage of the Nacimiento Formation, particularly near the formation base, but not in the Naashoibito Member, indicates episodic warmth and short (104 years) intervals of more intense weathering conditions during the very early Danian as compared to the late Maastrichtian. Aside from short warm intervals, the overall palaeoclimate during deposition of both formations was warm and consistently subhumid to humid and seasonal, suggesting no substantial long‐term (105–106) climate change took place across the Cretaceous–Palaeogene boundary in the San Juan Basin. [ABSTRACT FROM AUTHOR]

Sedimentation basins are structures that separate suspended sediments from river flows at irrigation intakes. There are many ways to design these sedimentation basins, some of which lead to unrealistic results because of their simplifying assumptions. Some of these methods are complex and are extremely difficult to use. Meanwhile, other methods to reduce the above problems have been proposed by a number of researchers that are based on laboratory or analytical studies. Due to the existence of various models, it is difficult to determine which approach is the most appropriate model. Here, by introducing multiple methods, their performance has been evaluated by comparison with laboratory data. Experiments were conducted on a flume 12 m in length, 1.2 m in width, and 0.5 m in height for three sediment sizes and for different discharges. Trapping efficiencies were calculated based on the remaining sediment in the invert of the flume after completion of the experiment. The results showed that the United States bureau of reclamation model shows a high efficiency of the sedimentation basins. In addition, it was found that the efficiency estimates of this model are very sensitive to input parameters. Examination of various statistical characteristics showed that the trapping efficiency in this study is consistent with the Sarikaya and Einstein models. Also, a regression equation with an accuracy of RMS = 7.32 can be used to estimate the trapping efficiency in irrigation sediment basins. [ABSTRACT FROM AUTHOR]

Water is lifeline of species on earth. Various human activities deteriorated the quality of water and made it unhygienic to use. The present work evaluates the water quality of surface water of the Nainital lake, Uttarakhand, India. In this study, secondary water quality data for the summer, winter and monsoon seasons for the years 2019-2023 are used from the Uttarakhand Environment Protection and Pollution Control Board (UEPPCB). The surface water samples underwent a thorough physico-chemical investigation that included various parameters (pH, BOD, COD, EC, DO, Alkalinity, Cl, Ca, Mg, Hardness and TDS). The study reveals that EC, alkalinity, Ca, Mg and total hardness were observed beyond levels prescribed by BIS/ CPCB/WHO standards in all three seasons of 2019, 2020, 2021, 2022 and 2023 at Nainital lake water intake. The study addresses multiple lake water quality restoration interventions such as aeration systems, sedimentation basins, nutrients management, phytoremediation, biomanipulation. [ABSTRACT FROM AUTHOR]

A new concept of the formation of glauconite from the Paleocene deposits of the sedimentary cover of the southwestern part of the Near-Volga monocline is presented. It was formed as a result of halmyrolysis of ash material in lake conditions. Glauconitization is confined to the Paleogene thermal maximum and the periphery of active volcanism along the entire mobile belt. In this connection, it is widely distributed in the Paleogene deposits. Structural and crystal-chemical features of glauconite, stages of crystallization of its aggregates, paragenetic associations with smectite, kaolinite, and zeolite, as well as the presence of ore minerals indicate its authigenic origin. The authigenic origin is confined to the formations of temporary, episodically submerging shallow marine basins. An applied scheme of discrimination of glauconites by their crystallochemical features has been developed. The discrimination diagram can be used to determine the specific conditions of the sedimentation basin, which are expressed in the progradation cycles of glauconite accumulation. The cycles were controlled by induced depressions within the Russian plate. [ABSTRACT FROM AUTHOR]

Field evidence from the northern Cotentin Peninsula and regional data are used to construct a tectono-stratigraphic model for the Ordovician which characterizes basin development in the North Armorican Massif. In La Hague, 15 m of transgressive marine sandstone belongs to the Dapingian age Grès Armoricain Formation which onlaps lower Cambrian, rift-fill deposits via an unconformity. Approximately 450 m of overlying Darriwilian strata are dominated by shallow marine sandstone showing hummocky cross-stratification with subordinate shales containing trace and body fossils. Together, these facies support an interpretation of offshore shallow marine strata overlying a break-up unconformity. Regional analysis indicates the time gap at the unconformity is 20–40 Ma and formed from crustal upwarping, which was greatest in the north of the Armorican Massif. Dapingian strata (Grès Armoricain) thins irregularly to the north (0–94 m), interpreted to reflect passive onlap onto residual relief associated with the uplift and the initiation of thermal subsidence on the margin. The succeeding Darriwilian strata (Schistes de Beaumont to Grès de May) conversely display a steady thickening (161–623 m) to the north, the stratal patterns suggesting that from the Darriwilian onwards, the ocean basin to the north was firmly established as the main locus of subsidence on the continental margin. [ABSTRACT FROM AUTHOR]

Lithospheric foundering is hypothesized to contribute to the formation of Earth's largest continental plateaus, but the predicted effects remain poorly constrained, especially considering variations in crustal strength. Here we propose that lithospheric foundering involving a hot, weak crust can explain aspects of topography and crustal deformation in mountain belts. We explore this hypothesis using numerical models of orogenesis and foundering in the Southern Puna Plateau in the Central Andes. Contrary to previous models of foundering involving a strong crust, which are characterized by subsidence and shortening, a weak crust results in surface uplift and upper‐crustal horizontal extension, which is accommodated by horizontal shortening in peripheral regions. Our model explains data such as the timing and location of exhumation and basin sedimentation as a response to foundering. The model also shows that foundering is capable of converting a high‐relief, broken‐foreland region into a high‐elevation, low‐relief plateau in a convergent tectonic setting. Plain Language Summary: Thickened crust can gravitationally unstable and founder into the mantle. This process could contribute to the formation of large plateaus such as Tibet and the Central Andes, which are composed of hot, felsic, and therefore weak crust. However, existing models have not thoroughly considered the implications of lithospheric foundering beneath a weak crust. We present numerical modeling experiments that show that a lithospheric drip can cause crustal flow and spreading, even when it takes place within a convergent tectonic setting, such as a major mountain belt. By comparing our models to geologic data from the Central Andes, we suggest that this scenario can explain many intriguing geological puzzles within the Puna Plateau, such as the timing and distribution of horizontal extension, the thickening of the crust, and the uplift history of the plateau. Future studies should consider the possibility of a weak, flowing crust during a lithospheric foundering event. Key Points: Lithospheric foundering under a hot, weak crust causes syn‐convergent, upper‐crustal extensionOur models successfully explain the Cenozoic uplift and deformation of the Puna Plateau as a result of this processThis style of foundering has been overlooked but may apply to other large orogens [ABSTRACT FROM AUTHOR]

Local factors of the formation of coastal-marine rare metal–titanium placers were analyzed for creating the prospecting-oriented geological-dynamic model that allows to predict the prospects of rare metal–titanium placer mineralization. Their influence on the structure, composition, localization of placer concentrations within sedimentation basins, and dynamic interaction during the formation of productive sediments was investigated. Based on the works of previous researchers devoted to the historical-geological and regional tectonic factors controlling the formation of these placers, we developed a qualitative model of the formation of placer concentrations in different rank areas (districts, clusters, fields, and specified placer bodies), which can serve as a basis for the creation of prospecting-orientated model of the deposit and planning the exploration and evaluation work. Among the factors controlling the formation of placers, we can identify: hydrodynamic processes characterizing the types and mechanisms of placer concentrations (littoral and sublittoral) within the dynamically active coastal zone; lithodynamic processes depending on the abrasion-accumulative setting of the coast and parameters of the alongshore sediment flow; structural-dynamic processes controlling the formation of economically significant productive deposits and their localization; and the transgressive-regressive setting of a basin that determines the structure of placer bodies and their transformation at the postsedimentary stage. Large economically significant rare metal–titanium placer deposits are only formed under conditions of a joint realization of the positive potential of these factors. The developed qualitative model can serve as a basis for digitizing the forecasting of rare metal–titanium placer mineralization. [ABSTRACT FROM AUTHOR]

To constrain the relationship between the plate boundary dynamics and the basin sedimentation in the southwestern South China Block (SCB), we undertook detrital zircon U–Pb–Hf isotope compositions of the Lower‐Middle Triassic turbidite system in the Youjiang Basin and biotite 40Ar/39Ar thermochronology of the adjacent Lingshan granite. The detrital zircons from Lower Triassic clastic rocks are dominated by age peaks at ~450 Ma and ~1,000 Ma and minor peaks at ~250–260 Ma with negative εHf(t) values (−6.4 to −10.1). In contrast, the Middle Triassic group contains more volcanic fragments and displays a different age peak at ~240–287 Ma with εHf(t) between −11.9 and 13.2 in addition to the former two peaks. These results suggest a potential provenance associated with juvenile and volcanic components in the adjacent region during the Middle Triassic. A summary of the Triassic tectonothermal history suggests that the eastern Youjiang Basin and Yunkai Terrane were uplifted throughout the Triassic, while the northeastern Indochina Block on the west of the SCB was uplifted mainly during the Middle Triassic. Combined with the palaeocurrent reconstruction, we infer that the turbidite system was filled primarily from east to west during the Early Triassic, mainly controlled by the Palaeo‐Pacific plate subduction. Subsequently, the Middle Triassic turbidite system involved juvenile and volcanic components from the eastern SCB and northeastern Indochina Block in addition to the Early Triassic provenance, as a result of dual impact from the Palaeo‐Pacific plate subduction and Indochina Block collision. [ABSTRACT FROM AUTHOR]

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In western Greece is the Pindos Foreland Basin, a geological depression that contains approximately 2500 m of mainly Upper Eocene to Lower Oligocene submarine fans deposits. Despite the extensive stratigraphic and structural research that has defined the basin as a foreland basin that developed adjacent to Pindos Orogen, the impact of orogenic history and erosion on sedimentation has not been evaluated. This study investigates the origin and tectonic setting of the central Pindos Foreland Basin using new provenance data. Petrographic and geochemical analyses suggest that the succession was primarily sourced by sedimentary, felsic, and intermediate igneous, and low-grade metamorphic source rocks. The geochemical analysis reveals that the sediments are immature and have undergone little to moderate weathering, and low degrees of sediment recycling and sorting. A secondary mafic source with high Cr and Ni contents and high Cr/V ratios. The provenance data indicate that Pindos Orogen represents the source region and agree with the existing sedimentological and palaeocurrent research. The Pindos sedimentary and Pelagonian volcano-sedimentary units, mixed with a mafic source (Pindos ophiolitic units) and low grade metamorphics produce the observed chemical and petrographic variance. Multidimensional discrimination diagrams suggest sediment sources from a collisional setting and confirm the active continental edge setting. The provenance data display an up-section increase in lithic fragments, recording the growing history of the Pindos orogen and the gradual exhumation of the source regions. This study offers an example of the sedimentary provenance trend in an evolving pro foreland basin. [ABSTRACT FROM AUTHOR]

In the development of water resources projects with large hydraulic infrastructures, alterations to the natural flow regime will increase the erosive processes on the discharge structures due to variability of the turbulent velocities and the particle transport. We analyzed the case of the Mazar dam, a project designed to regulate the solid and liquid flows that come from the Paute river basin. Erosive processes of great magnitude are generated in the stilling basin of Mazar dam, due to the intensity of turbulent velocities produced in extreme events. We applied the Delft3D numerical model to simulate the hydrodynamic and sediment transport conditions to evaluate the stability conditions of the Mazar dam stilling basin. With the results obtained, vulnerable zones have been identified in the stilling basin. We recommended mitigation measures with the installation of a geomembrane to reduce the erosive processes in the vulnerable zones. [ABSTRACT FROM AUTHOR]

Rounded argillite clasts within the lower Gowganda Formation of the Huronian Supergroup near Whitefish Falls, Ontario, have been historically mapped as Sudbury Breccia, implying that their formation was initiated by the Sudbury meteorite impact event. Alternative genetic models proposed to explain the breccia at Whitefish Falls include formation through intrusion of diabase into wet sediment accompanied by soft-sediment deformation events. Outcrops in the Whitefish Falls area contain clear evidence for early post-depositional fracturing: flow of argillites into brittle fractured sandstones. Linking these geological processes suggests that the formation of the breccia at Whitefish Falls was generated by faulting of the Huronian sedimentary basin during the sedimentation of the Gowganda argillites. Using a GIS approach to compare the distribution of known breccia bodies with mapped lithology and structure, it is apparent that the term Sudbury Breccia has been applied to two types of breccias. First, true Sudbury Breccia, which is characterised by rounded heterogeneous clasts in an aphanitic matrix, is only found in proximity to the Sudbury Impact crater. The distribution of the second, primarily sediment derived, type of breccia, as seen at Whitefish Falls, is strongly associated with mapped faults and regional-scale basement discontinuities, as defined by gravity and magnetic data. Since this type of breccia is present throughout the entire Huronian sedimentary sequence, the term "Huronian Breccia" is more appropriate. This breccia is not the result of a single geological event but rather episodes of fault activity, as the geometry of the Huronian basin evolved over time. [ABSTRACT FROM AUTHOR]

A settling basin is generally provided close to the headwork of hydropower projects to facilitate settlement and exclusion of sediments to meet the stipulated design criteria. The settling basin minimizes the wear and tear of the underwater components of the power plant. The design of inlet transition and inlet zone of the basin has to consider non-uniform flow conditions and formation of eddies. The configuration of inlet transition has a significant effect on the water and sediment flow pattern at the entry point and in the inlet zone as such and consequently on the overall settling efficiency of the basin. The review of model studies and case studies on the settling basin of run-of-river projects in the Himalayan and other mountainous regions, with particular reference to the inlet transition design, brings to light the strengths and limitations of physical and numerical models, merits of combining both types of models in specific cases and also the important parameters to be considered in model studies. The design features for inlet transition in open channel and pressure flow basin projects are also discussed. Importance of monitoring and reporting the performance of existing settling basins for improving the design of inlet transition of settling basins in future has been highlighted. [ABSTRACT FROM AUTHOR]

Lakes may take a while to respond to management interventions because of the management implications of incremental development and degradation issues. This includes the requirement for the ongoing participation of key lake basin management institutions and their operations. This study's objective is to assess the impacts of land use activities along the Kenyir Lake Basin based on the sedimentation problem level. There are a few hydrological methods that are necessary indicators to measure the level of sediment production, such as Total Suspended Solid (TSS), area of sub-catchment, river discharge measurement, and annual sediment load production. The results showed that the sub-catchment of Besar River released the lowest annual average estimation at 3833.70 kg/km2/year, and the sub-catchment of Kenyir River produced the highest annual average estimation at 128,070.86 kg/km2/year for annual sediment load flow produced from tributary rivers into Kenyir Lake. Kenyir Lake Basin's downstream and midstream regions had higher sediment load values than its upstream regions. This study highlighted the significance of the effects of anthropogenic factors, hydrological, geomorphological, growth, and developmental factors, and climate changes as the key variables attributing to the sedimentation phenomenon along the Kenyir Lake Basin. The construction of a long-term lake or reservoir catchment development and management plan, combined with the formation of a vision and comprehensive strategic plan, are vital components of sound management practice. The efficient implementation of the suggested watershed management programmes depends on the active involvement of all significant catchment stakeholders. [ABSTRACT FROM AUTHOR]

The water wealth and terrain head of the Himalayas are nature's gift and a bounty. Whereas concentration of the sediments carried by the rivers Indus, Ganga, Brahmaputra and their tributaries exceeds 2,000 p.p.m. [Extracted from the article]

Modernising irrigation is a top priority in Indonesia, with managing irrigation water supply services effectively and efficiently, particularly in providing value to farmers. Sediment traps are an essential component of the head structure in irrigation. Vortex Settling Desilting Basins (VSDB) have inherent advantages over other types of sediment-removal desilting basins. The experiments were conducted under three different discharge scenarios, and three-dimensional flow velocities were measured. The streamlines and velocity vectors in the horizontal superimposed sections were drawn and analysed then for the incipient motion of sediment. This study presents the results of experimental research that was accomplished in a VSDB to observe the slope orifice chamber with 1:10, 1:5 and 1:2. The method used numerical methods with CFD simulations by Ansys R.21 2020 (student version) to approach geometric shapes then laboratory experiments with a model scale 1:40 prototype to an undistorted 3-D physical model. Comparing the magnitude of the velocity and streamlined path in horizontal sections with the occurrence of secondary in radial sections revealed that the flow in the vortex direction plays a higher role in the removal efficiency of the desilting basin. As a result, by comparing the performance of rectangular shapes with the same hydraulic parameters, the slope orifice chamber of 1:5 is more effective in case of deposition and removal than another slope chamber. Eleven times running, it settled 84.90% of the sediment fraction and left a sediment fraction of 12.10%, higher than the effectiveness of the performance of sediment traps with a rectangular shape. [ABSTRACT FROM AUTHOR]

Coastal Louisiana is currently experiencing high rates of wetland loss and large-scale ecosystem restoration is being implemented. One of the largest and most novel restoration projects is a controlled sediment diversion, proposed to rebuild and sustain wetlands by diverting sediment- and nutrient-rich water from the Mississippi River. However, the impact of this proposed sediment diversion on the nutrient budget of the receiving basin is largely unknown. A water quality model was developed to investigate the impact of the planned Mid-Barataria Sediment Diversion on the nutrient budget of the Barataria Basin (herein referred to as 'the Basin'). The model results indicate that the planned diversion will increase TN and TP pools by about 38% and 17%, respectively, even with TN and TP loadings that increase by >300%. Water quality model results suggest that the increase of nutrients in the basin will be mitigated by increased advection transport (i.e., decreased residence time from ~170 days to ~40 days, leading to greater flushing) and increased removal via assimilation, denitrification, and settling within the Basin. Advection transport resulted in higher TN removal in the Basin than other processes, such as uptake or denitrification. Approximately 25% of the additional TN loading and 30% of the additional TP loading were processed within the Basin through the assimilation of phytoplankton and wetland vegetation, denitrification, and burial in the sediment/soils. These nutrient budgets help to better understand how the planned large-scale sediment diversion project may change the future ecological conditions within the estuaries of coastal Louisiana and near-shore northern Gulf of Mexico. [ABSTRACT FROM AUTHOR]

Periods of formation of different sedimentary lithotypes were determined using the results of the study of modern sedimentation processes in the Storefjorden Strait (West Spitsbergen). The chronology of sedimentation was established from variations in specific activity of 210Pb and 226Ra and verified by 137Cs data. Sedimentation rates have varied considerably over the last century in different parts of the sedimentation basin, ranging from 0.04 to 0.3 cm/yr. Sedimentation in the Storefjorden Strait was closely related to changing climatic conditions. Climatic factors (air temperature, atmospheric precipitation) have a different effect in morphologically different sections of the sedimentation basin. In the south of the strait, lithotypes are determined by an oceanological factor (bottom current). Despite the changes in sedimentation rate, the lithotype in the south of Storefjorden has remained stable for more than 100 years. In the north and in the central part of the strait, cooling in the period from 1970 to 1995 caused a change in the bottom sediment structure. [ABSTRACT FROM AUTHOR]

Petrographic, whole‐rock geochemical and geochronological analysis of polymictic conglomerate, associated siltstone and greywacke in the Neoarchean Gadag Greenstone Belt in the Western Dharwar Craton, India, provides new insights into sedimentary provenance and tectonic setting. The polymictic conglomerate contains granitic, gneissic, felsic and mafic volcanic, quartzite and banded ferruginous chert clasts within a quartzo‐feldspathic matrix. Framework grains in the siltstone and greywacke are quartz, feldspar with rock fragments, embedded in a chlorite‐dominant matrix. The chemical index of alteration values (~70) and A‐CN‐K plot for the rocks suggest a low‐to‐moderate degree of weathering. Rare earth element (REE) patterns show moderate fractionation (LaN/YbN ~ 12.31) with a weak negative europium anomaly (0.82). Enrichment in transition elements (Ni, Cr, Co, Sc) and depletion in high‐field‐strength elements, as well as relatively low La/Co (0.62), moderate to high Th/Yb (3.06), La/Th (5.16), La/Yb (17.5), and La/Sc (~2.37) ratios, suggest a mixed felsic‐mafic provenance. U–Pb dating of detrital zircon from the conglomerate and greywacke revealed major age peaks at ca. (3.2, 2.9, 2.8, 2.6, 2.5 Ga) and a maximum age of deposition of 2,508 ± 26 Ma, 2,493 ± 20 Ma, respectively. The above data suggest low to moderately weathered proximal sources for both conglomerate and greywacke, indicating that these two rock types were not deposited simultaneously, but rather separately. The association of these conglomerates and greywacke with continental arc‐related volcanics indicates the closing of an arc at the time of sedimentation. Complex provenance consisting of recycled and magmatic arc during basin closure confirm the notion of modern style plate tectonics operating during Neoarchaean. [ABSTRACT FROM AUTHOR]

Modern irrigation schemes are increasingly demand-based, which means that the crop water requirements determine the water flow in a canal. The sediment transport aspect is a significant factor in irrigation development as it determines to a large extent the sustainability of an irrigation scheme, particularly in the case of unlined canals in alluvial soils, and as a trigger in reducing the wet capacity of the irrigation canal. The conventional sediment traps with a rectangular shape, rapidly advancing development, are challenging to construct because they require adequate space. The Vortex Settling Desilting Basin (VSDB) has proposed to replace the rectangular shape with more effectiveness considering the more concise area, deposition rate and removal efficiency, and minimum human resources as an operator. The method uses numerical methods with Computational Fluid Dynamic (CFD) simulations by Ansys R.21 2020 Student to acquire a geometric shape approach, then laboratory experiments with a model scale 1:40 prototype to an undistorted 3D physical model. This study aims to develop a two-dimensional numerical model and the optimal regression equations for determining settling basin dimension and then simulate and compare the efficiency of the selected settling basins. The VSDB shape is slimmer at 42% than the rectangular shape by optimizing the slope orifice chamber. As a result, by comparing the performance of rectangular sediment traps with the appleto- apple hydraulic parameters and sediment variables, the results obtained based on deposition performance increased from 69.12% to 84.90% and flushing performance by leaving the minimum sediment fraction increased from 53.33% to 87.90%. [ABSTRACT FROM AUTHOR]

Background and Objectives Pre-sedimentation basins are considered as the major and important components in water treatment process through conventional method. Because of the high cost of constructing these basins, which is approximately 30% of the total costs of water treatment plants, modeling and optimum performance of pre-sedimentation basins are very important. In pre-sedimentation basins, because of the existence of velocity gradients, secondary and rotational flows occur. In order to increase the performance of a pre-sedimentation basin (clarifier), it is essential to have a uniform and calm flow field. The use of suitable baffle configurations may help forming favorable flow field and increase the efficiency of the pre-sedimentation basins. In order to find the proper position of a baffle in a rectangular sedimentation basin, computational investigations are performed. The first step to optimize pre-sedimentation basin is accurate calculation of the velocity field and the volume of rotation zones. Flow guiding blades can also be used to depreciate the inlet jet and reduce turbulent kinetic energy. Because of the flow complexity and also the effects of scale, physical models can not solely provide a clear understanding of the physics governing the flow field and it is necessary to study this phenomenon numerically along with field and experimental studies. The numerical results were calibrated with experimental results of Shahrokhi et al. (2011) and Imam et al. (1984). Flow simulation was performed in 3D and flow velocity profiles were compared with the experimental results in different sections of a pre-sedimentation basin. Then, in order to sedimentation investigation in the pre-sedimentation basin, advection and dispersion equation of sediment concentration was solved simultaneously with the governing equations of flow. Methodology The first step to optimize pre-sedimentation basins is accurate simulation of the velocity field and the volume of rotation zones. In the present study, numerical simulation of flow was investigated in a pre-sedimentation basin using SSIIM and Fluent models. Continuity and momentum equations were solved using finite volume method. Flow analysis was done steady by the SIMPLE algorithm for velocity and pressure coupling. Discrete method of continuity equations, momentum, turbulent kinetic energy, Reynolds stress drop and discretion of pressure equation are standard. Findings The results of the vertical distribution of sediment concentration profiles in different sections of the basin were compared with the experimental and numerical results of other researchers. Finally, the effect of flow guiding blades on the flow pattern and the efficiency of sedimentation in the presedimentation ponds were investigated. The comparison showed that there is a good agreement between numerical and experimental study with an average error of 6%. Conclusion Flow rate is one of the effective parameters on creating a rotational zone inside the basins. With increasing the inlet flow rate from 0.002 to 0.01 cubic meters per second, the length of the rotational zone has increased 25% and the width of the rotating zone has increased 45%. The secondary and rotational currents formed at the entrance of the basin are two small rotational zones and approaching the middle of the basin and formation of flow separation zones, the number of rotating areas and their dimensions have increased. From the beginning to the middle of the basin, the shear stress is increased. In the sections x = 0.46 m and x = 0.82 m, the amount of shear stress is maximum. Amount of energy in the middle of the depth has decreased by 40% compared to the water level and about 60% compared to the floor of the sedimentation basin. It showed that there is a good agreement between the numerical and experimental results. It also indicated high ability of SSIIM in predicting distribution of sediment concentration profiles in pre-sedimentation basins. With increasing flow depth, the sediment concentration decreases. In the section x = 1.58 m, the sediment concentration near the free surface is 44 mg L-1, which decreased by 57.48% compared to the concentration of sediment in the basin bed. In the case without the guide blade, near the free surface of the stream, the sediment concentration was decreased. Also, in the middle of the basin, due to the turbulence of the flow and the rotational areas, the secondary current strength was maximal and decreased as it approached the end of the basin. [ABSTRACT FROM AUTHOR]

In this paper, we present a study of the diffusion properties of a deterministic model for settling particles in two displacement dimensions. The particularities of the novel deterministic model include the generation of Brownian motion and a two-dimensional displacement model without stochastic processes, which are governed by a set of six differential equations. This model is a piecewise system consisting of subsystems governed by jerk equations. With this model, we can consider different conditions of diffusion in both the dimensions and size of the space where the particles are dispersed. The settling time versus the dispersion medium and its size, as well as the average settling time and its probability distributions, are analyzed. Furthermore, the probability distributions for the settling location are presented for the changes in the diffusion parameters and space size. Finally, the basins of attraction for the settling positions are shown as a function of each dimensional diffusion parameter and for the medium size. [ABSTRACT FROM AUTHOR]

The halogenesis of the Messinian Tuz Gölü Basin corresponds to the sulfate type and the magnesium sulfate subtype. Compared to the Messinian Sea brines, they have a slightly higher [Na+] concentration, which is 96.6–116.4 g/L, and a much lower [K+] concentration, ranging from 0.1 to 2.35 g/L. During salt sedimentation, the [Mg2+] concentration ranged from 6.1 to 14.0 g/L, and the [SO42−] concentration from 18.2 to 4.5 g/L. Physical–chemical reactions in the basin's near-surface and bottom waters during the suspension of halite deposition had a decisive influence on the significant reduction of [SO42−] sedimentation brines. During these periods, there was an intensive influx of Ca(HCO3)2 into the sedimentation basin and the formation of glauberite layers. The formation of the glauberite resulted from the slow dissolution of pre-deposited finely dispersed metastable minerals—gypsum, sodium syngenite, or mirabilite. In fluid inclusions in the halite, the sulfate minerals being allogenic crystals of calcium sulfate, are represented by gypsum, bassanite, and anhydrite. Additionally, as the other sulfate minerals, glauberite, anhydrite, and thenardite are found within halite crystals. Sharp fluctuations in daytime air temperatures characterized climatic indicators of the summer period in the Tuz Gölü region: 15.6–49.1 °C. In the spring or cool summer–autumn period, the daytime air temperature in the region ranged from 15.7–22.1 °C, and in late spring and early summer, it ranged from 20.6 °C to 35.0 °C. During some periods, the Tuz Gölü halite crystallized at 61.8–73.5 °C. The extreme high-temperature crystallization regime at the bottom of the salt-bearing basin was achieved due to the emergence of a vertical thermohaline structure. The "greenhouse effect" in the Tuz Gölü was established only briefly but was periodically renewed due to the influx of "fresh" waters. [ABSTRACT FROM AUTHOR]

Geochemical study in the siliciclastic sediments of a basin provides an understanding of palaeoclimate, provenance and subsequently, it can be used to reconstruct the palaeo‐tectonics and evolution of the basin. Sedimentation in the Gondwana basins, worldwide, generally provides a record of climatic fluctuations and evidences of the Permo‐Triassic mass extinction. In spite of its global importance, our knowledge about the nature of sedimentation, basin development and conceptual regional tectonic model in the Satpura Basin, one of the Gondwana basins of India is limited. Major and trace element concentrations of the mudstones from the Denwa Formation along with the existing geochemical data of other formations are studied here for establishing a comprehensive idea about the palaeoclimate, tectonic settings, provenance and basin evolution. The composition of the sediments in the lowermost Talchir Formation revealed cold and dry climatic conditions at the sources, whereas the sources of the sediments for the overlying formations have experienced warm, humid and semiarid climates. The contributions of the mafic rock‐derived sediments are relatively higher in the Talchir, Barakar and Motur formations compared to the overlying formations. Approximately 60% of the sediments in the overlying Bijori, Pachmarhi and Denwa formations were derived from the felsic volcanic rocks and granites of the Sausar Mobile Belt and Betul‐Chindwara Mobile Belt (BCMB) with minor inputs from mafic volcanic rocks of the BCMB. Furthermore, the sediments of the Talchir Formation were derived from the BCMB when they became tectonically active, whereas the sediments in the younger formations have been derived from a passive tectonic setting. [ABSTRACT FROM AUTHOR]