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• The Late Tonian to Cambrian Xiang-Gan-Yue basin in the South China recorded rifting, passive margin to foreland setting. • Northwestward propagation of siliciclastic sedimentation occurred in this basin. • Sediment source for the basin changed continuously from the Yangtze to Cathaysia Block during Cryogenian to Ordovicaian. • This basin may record sedimentation after the closure of the South China Ocean. The late Tonian to Cambrian sedimentary sequences in the Xiang-Gui-Yue (XGY) Basin across the potential suture zone between the Yangtze and Cathaysia blocks preserves invaluable information on the geological evolution of the South China Block, while the sedimentary provenance is not well constrained and tectonic affinity of the basin is still highly controversial. This study presents systematic provenance analysis of late Tonian to Cambrian clastic rocks to reconstruct the formation and evolution of sedimentary basin. A significant change from dominant 900–700 Ma to dominant 1300–900 Ma zircons in sediments has been observed along with the basin evolution. It has been widely considered that the 900–700 Ma detritus are largely from the Yangtze Block in the northwest, while the 1300–900 Ma detritus are from the Cathaysia Block in the southeast or terranes linked to the Cathyasia Block at that time. More remarkably, the provenance transition occurred at Cryogenian, Ediacaran and Cambrian in the southeastern, central and northwestern parts of the XGY Basin, respectively. All the above observation indicates the Yangtze-derived detritus arrived at the southeast end of the basin as early as late Tonian and gradually faded away until at least Ordovician, as probably caused by the denudation of the Jiangnan Orogenic Belt after the amalgamation of the Yangtze and Cathaysia blocks. On the other hand, the Cathaysia-derived detritus became dominant due to the uplift of the Cathaysia Block. The XGY Basin was a rift basin until ca. 660 Ma, evolved into a passive margin setting during Ediacaran-early Cambrian, and became a foreland basin after the middie-late Cambrian. Collectively, the provenance variation from late Tonian to Cambrian basin suggests that the Yangtze and Cathaysia blocks may have been amalgamated before late Tonian and an intra-plate basin has been developed along the orogenic belt, allowing the formation and evolution of the XGY Basin. [ABSTRACT FROM AUTHOR]

A multidisciplinary approach, involving geochemical, sedimentological and oceanographic analyses, was employed to examine the distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in a strongly anthropized area of the marginal Adriatic Sea (Mediterranean basin). The investigation into PAH distribution considered the grain size and biogeochemical properties of the sediments, as well as in relation to the main oceanographic processes and river inputs. Both biogeochemical and hydrographical inputs regulated the sedimentation of organic particles, influencing the distribution of PAHs. The results indicated PAH levels in 116 marine surface sediments ranging from 4 to 235 ng g−1 (average 55 ng g−1). The distribution of PAHs in Adriatic Sea surface sediments aligned with a higher clayey sedimentation in the deeper basin areas of the Middle Adriatic Depression. [Display omitted] • A multidisciplinary approach combined geochemical and oceanographic aspects. • Level of PAHs in a large area of central and southern Adriatic Sea was evaluated. • The biogeochemical and hydrographical factors regulated PAH distributions. [ABSTRACT FROM AUTHOR]

The Parnaíba intracratonic basin exhibits sedimentation that reflects the different evolutionary stages of climate and paleogeography in the West Gondwana supercontinent. In this regard, we conducted a study comprising the Poti Formation in the southeast of Itaueira and Floriano regions in Piauí State, within the Parnaíba Basin. The facies analysis enabled the establishment of the depositional model for the study area, comprising ten sedimentary facies separated into two facies associations (FA) deposited in a shallow platform environment dominated by storm waves: Upper Shoreface (FA-1) and Lower Shoreface/Offshore transition (FA-2). It was possible to determine that the wave base line constantly varied, and a high-energy event provided the deposition of sediments with fine-to coarse-grained sandstone from FA-1 over those of FA-2, creating a first-order erosive surface (surf diastema) with a gradient varying from 40 to 45° that limits the two distinct facies association. This sedimentary event resulted in the excavation of the muddy offshore sediments by the lower shoreface, resulting in coarsening- and thickening-upward sandstones lying mostly under fine-grained sandstone with hummocky cross-stratifications. In the paleogeographic context, the cross-stratification paleocurrent indicates a direction towards the NW and, to a lesser extent, the SW. This direction suggests a connection between the epicontinental sea formed in the Parnaíba Basin and the paleosea of Tethys in the Late Carboniferous. Petrographic analysis classified the sandstones as subarkose and quartzarenite. This study employed petrography, X-ray diffractometry, architectural elements, and facies analysis to make inferences about the depositional system, climate, and geomorphology of the storm and wave-dominated deposits of the Poti Formation. The occurrence of kaolinite and illite in the studied deposits are typical clay minerals of humid and hot (dry) climatic conditions, respectively. Therefore, the overall data indicates a shift from retrogradational to progradational deposits that records changes in facies association and climate conditions in the Late Carboniferous. • Facies analyses and facies association of the Visean Poti Formation. • Sedimentation in the Upper Carboniferous, West Gondwana. • Storm wave-dominated shallow platform depositional system of the Poti Formation. [ABSTRACT FROM AUTHOR]

The Uralian foredeep is a classical marginal structure located on the foreland of the Late Paleozoic Uralian Orogen. It is subdivided into several depressions/sedimentation basins. This paper presents the analysis of the REE and Th distribution in the Middle Carboniferous and Lower Permian clay rocks of the Yuryuzan–Sylva Depression. This structure, like other depressions of the foredeep, is made up of diverse associations of the first sedimentation cycle clastic and clay rocks, which were formed during the orogen erosion. In the (La/Yb)N–Eu/Eu* and (La/Yb)N–Th diagrams, individual and average data points are confined to the field of bottom sediments of mouths of modern rivers draining volcanic provinces. This likely suggests a homogeneous composition of orogen provenance in the Carboniferous and Early Permian. [ABSTRACT FROM AUTHOR]

• Five lake sediment records in the Adirondacks region of New York (USA) were studied. • Plant wax n -alkane 14C ages at the time of sediment deposition were determined. • The average n -alkane 14C age initial for all lakes was 400 14C yr. • The age of n -alkanes were almost always older (offset) than the age of the sediments. • Age offsets are caused by sediment focusing and reworking of soil-derived n -alkanes. Lacustrine sediments have the potential to preserve paleoenvironmental proxies such as terrestrial plant waxes at high temporal resolution. The temporal fidelity of plant wax records, however, can be up to several thousand years older than the corresponding sediment, based on compound-specific radiocarbon (14C) analysis. Unfortunately, the factors controlling 14C age offsets between plant waxes and sediments are not well understood. The aims of this study are to quantify and compare plant wax n -alkane 14C age offsets among lakes within the same region, and to determine if drainage and lake basin differences (e.g., size, relief, drainage basin morphology, fluvial inputs) influence these offsets. We collected sediments from five lakes in the Adirondack Mountains, NY, USA that lack petrogenic sources of n -alkanes, and range in drainage basin characteristics. Sediment age models were constructed for each lake using a combination of sediment 210Pb, 137Cs, and macrofossil 14C ages, and compared to 14C ages of long-chain (n -C 27 , n -C 29 , n -C 31) alkanes sampled from Holocene and Late Glacial aged sediments. The n -alkane 14C age initial is a measure of the age offset in n -alkanes relative to the sediment they are deposited in. Across all lakes, the n -alkane 14C age initial ranged from penecontemporaneous to 2440 14C yr. This oldest n -alkane 14C age initial is significantly outside the distribution of all other samples; when excluded, the overall mean n -alkane 14C age initial was 400 ± 255 14C yr (n = 23). The largest n -alkane 14C age initial values were observed in the last 1 cal kyr BP (565 ± 180 14C yr (1σ), n = 12)) compared to sediments deposited between 1 and 13 cal kyr BP (220 ± 195 14C yr (1σ), n = 11)). These age offsets develop early after initial lake basin sedimentation and follow a similar pattern in all of the lakes despite differences in lake basin and catchment size, relief, and geomorphology. We speculate that 14C age offsets occur due to reworking of older n -alkanes stored in drainage basin sediments and soils and this mechanism is most effective in the last ∼1 kyr. Regardless, lakes in temperate forested metamorphic bedrock terrains have relatively small and stable n -alkane age offsets compared with lakes with extensive catchment soils or anthropogenic disturbance. By targeting lakes with minimal catchment soils, age offsets may be reduced, thereby minimizing attenuation or age distortion of climate signals in plant wax isotopic records. [ABSTRACT FROM AUTHOR]

The chemical and isotopic compositions of manganese carbonate and oxide ores and host dolomites of the Porozhinsk deposit are studied. Manganese carbonates are characterized by low values of δ13C (–19.0 to –8.4‰, PDB) and δ18O (8.8 to 27.3‰, SMOW). These data indicate the participation in their formation of the isotopically light carbon from oxidized organic matter, and the water of ore-depositing solutions was most likely meteogenic. The host dolomites (Pod"emsk Formation, Chapa Group) are characterized by a heavier isotopic composition of carbon (2.3‒2.6‰) and oxygen (22.5‒31.3‰) that are typical of marine sedimentary carbonates in the Late Proterozoic sedimentation basin. The simplest organisms played a significant role in the genesis of manganese ores. Microbial structures were preserved in manganese carbonates and oxides. [ABSTRACT FROM AUTHOR]

Algal growth in water treatment plants can lead to the introduction of toxin and odour compounds from cyanobacteria and causes filter fouling. Here, we investigate the use of woven polypropylene covers and a proprietary copper sulfate formulation (EarthTec) to prevent algal growth within mesocosms designed to simulate settling basins. Chlorophyll a, soluble nutrients, weather patterns and cyanobacterial gene abundance were measured. The covers suppressed algal and cyanobacterial growth in mesocosms, likely due to a combination of light blockage and prevention of insects from entering the mesocosms. In contrast, mesocosms amended with EarthTec exhibited little difference from the control mesocosms in terms of algal growth. qPCR analysis revealed that only a small fraction of cyanobacteria in the system contained genes necessary for the production of the microcystin toxin. Despite differences between mesocosms and full‐scale settling basins, the data here suggest that woven covers can suppress algal growth while minimising evaporative water losses. [ABSTRACT FROM AUTHOR]

In order to understand the phosphorus (P) removal characteristics, which is the main controlling factor of eutrophication and algal blooms in a lake, the particle size distribution (PSD) and behavior were investigated in the inflow water and trapped sediments of Lake Saemangeum. A series of settling column tests (SCT) was carried out on the raw water taken from two influents of the lake to evaluate the sedimentation efficiency and P removal using two types of settling tests, discrete particle sedimentation (DPS) and flocculent particle sedimentation (FPS). In particular, the variation in the PSD and the P removal efficiency was traced to determine the impact of rain on the P treatment characteristics for three periods: the summer rainy period and before and after the rainy season. The PSD of the trapped sediments had increased in the rainy season, with a decrease after the rainy season. Based on the SCT results of the suspended solids, a longer sedimentation time for the DPS in the dry season was required than in the rainy season, whereas the sedimentation times for the FPS were not much different for the three periods. However, the clarifying velocity of the total phosphorus concentration was slower than the suspended solid concentration for both DPS and FPS, which suggest the particles containing phosphorus settled much more slowly than typical particles in both tests. The findings of this study will be important information in determining whether to add a coagulation process in the design of a sedimentation basin for the removal of phosphorus to be constructed for eutrophication and removal of lakes. [ABSTRACT FROM AUTHOR]

The massive growth of potentially toxic cyanobacteria in water supply reservoirs, such as Legedadi Reservoir (Ethiopia), poses a huge burden to water purification units and represents a serious threat to public health. In this study, we evaluated the efficiency of the flocculants/coagulants chitosan, Moringa oleifera seed (MOS), and poly-aluminium chloride (PAC) in settling cyanobacterial species present in the Legedadi Reservoir. We also tested whether coagulant-treated reservoir water promotes cyanobacteria growth. Our data showed that suspended solids in the turbid reservoir acted as ballast, thereby enhancing settling and hence the removal of cyanobacterial species coagulated with chitosan, Moringa oleifera seed, or their combination. Compared to other coagulants, MOS of 30 mg/L concentration, with the removal efficiency of 93.6%, was the most effective in removing cyanobacterial species without causing cell lysis. Contrary to our expectation, PAC was the least effective coagulant. Moreover, reservoir water treated with MOS alone or MOS combined with chitosan did not support any growth of cyanobacteria during the first two weeks of the experiment. Our data indicate that the efficacy of a flocculant/coagulant in the removal of cyanobacteria is influenced by the uniqueness of individual lakes/reservoirs, implying that mitigation methods should consider the unique characteristic of the lake/reservoir. [ABSTRACT FROM AUTHOR]

The primary separation unit (PSU) splits the organic load on the water and resource recovery facility (WRRF) between the primary sludge (PS) anaerobic digester (AD), where energy can be generated, and the biological nutrient removal (BNR) activated sludge (AS) reactor, where energy is consumed. With a CHONP element massbalanced plant-wide stoichiometric and kinetic steady-state model, this paper explores quantitatively the impact of four cases of increasing organics removal efficiencies in the PSU on (i) settled wastewater characteristics, (ii) balanced solids retention time (SRT) of the Modified Ludzack-Ettinger (MLE) and University of Cape Town/Johannesburg (UCT/JHB) systems for lowest economical effluent N and P concentrations, (iii) reactor volume, (iv) energy consumption for aeration, pumping and mixing, (v) energy generation by AD of PS and waste activated sludge (WAS), (vi) N&P content of the PS and WAS AD dewatering liquor (DWL) and (vii) final effluent N and P concentrations with and without enhanced biological P removal (EBPR), and looks for an optimum WRRF layout for maximum energy recovery without compromising effluent quality. For the low biogas yield from the WAS AD, decreasing as the SRT of the BNRAS system gets longer and with the added complexity of N&P removal from the digested sludge DWL, makes AD of WAS undesirable unless P recovery is required. Because the wastewater biodegradable particulate organics (BPO) have a low N&P content, it is better to divert more biodegradable particulate organics to the PSAD with enhanced primary separation than digest WAS - the PSAD DWL can be returned to the influent with relatively small impact on final effluent N and P concentration. [ABSTRACT FROM AUTHOR]

Diversified irrigation water has become an increasingly urgent need, due mainly to the limited fresh water resources and water pollution in China. Consequently, Yellow-river water irrigation has attracted more attention in recent decades. Since the Yellow River is the most sediment-filled river on earth, emitter clogging by a high concentration of sand has confined to the application of drip irrigation. Naturally, anti-clogging performance has been a commonly-used indicator to select the appropriate emitters. However, resource waste, high costs, and carbon footprint have posed a great challenge on both the anti-clogging performance and service life, when selecting the emitter products. In this study, an experimental field test was conducted to select emitter and lateral products suitable for drip irrigation with Yellow-River water, concurrently considering the anti-clogging performance, service life, system cost, and carbon footprint. SPSS principal component analysis (PCA) was used to establish selection indexes, and then to screen the suitable emitter products for various crops in different years. 16 kinds of emitters were also analyzed using Cristiansen Uniformity (CU) coefficient, including inlaid plain channel emitters, inlaid cylindrical emitters, single-wing labyrinth, and inlaid strip emitters. 3 crops were selected to evaluate the drip irrigation laterals. The experimental water was taken from the Wushen Canal in Hetao Irrigation District, and then filtered with sedimentation basin before entering into the drip irrigation system. Irrigation water was treated through the homogeneous filtration of a sand filter and a laminated filter. The work pressure was maintained at 0.1 MPa in operation. The Yellow-River water was operated for 9 hours/day with a flushing frequency of 60 h/time at a flow rate of 0.45 m/s and a flushing time of 6min, a total of 600 hours (flushing water) and 720 hours (non-flushing water). The results showed that there were significant differences in life cycle, cost and carbon footprint in different types of emitters. The longest life cycle was found in the inlaid plain channel emitters, followed by the inlaid cylindrical, inlaid strip, and single wing labyrinth emitters. The highest cost was found in the inlaid cylindrical emitters, followed by the inlaid plain channel, inlaid strip, and the single wing labyrinth emitters. CU of all emitters showed a slow and then rapid downward trend. The highest carbon footprint was the inlaid cylindrical emitters, followed by the inlaid plain channel, inlaid strip, and the single wing labyrinth emitters. Consequently, it was recommended to use the single wing labyrinth drip emitter with 2.94 L/h for a 1-year usage period (sunflower), plain channel emitter with 1.4 L/h for a 3-year usage period (lycium), and plain channel emitter with 2.8 L/h (with capillary flushing) for a 5-year usage period (alfalfa) in the crop irrigation in Inner Mongolia Hetao Irrigation Area. Capillary flushing demonstrated relatively low effects on the 1 and 3-year period (sunflower and lycium), however, the effects were more obvious on the 5-year use period (alfalfa). This finding can provide a new perspective for the selection of emitter products in large-scale drip irrigation with the high-sand Yellow-River water. [ABSTRACT FROM AUTHOR]

Analysis of a 195-cm core extracted from Polecat Bay (PB) in southern Alabama revealed that dramatic changes in diatom abundance/composition and sediment type took place sometime in the past. Examination of historical records and interviews with witnesses to industrial activity suggest that the changes were largely anthropogenically driven and caused by; (1) construction of the Mobile Bay Causeway, (2) spillage of bauxite dross from settling ponds, and (3) discharge of river dredge material directly into the bay. Analysis of the core showed increased clay content in its upper levels followed by an increase in motile benthic diatoms that tolerate turbid water, both likely the result of restricted circulation following construction of the Causeway. Energy-dispersive X-ray spectroscopy results coupled with archival evidence confirmed that between 1938 and 1983, bauxite dross was pumped into settling basins operated by ALCOA on Blakeney Island adjacent to PB, and that it periodically overflowed into the bay. Additional photographic evidence and interviews confirmed that in the late 1950s or early 1960s, the U.S. Army Corps of Engineers began filling ∼70% of PB with dredge material as part of a project to widen and deepen the Mobile River channel. This accelerated the rate of sedimentation and led to additional changes in diatom populations including a decline in non-motile diatoms in the most recent years. Our study demonstrates that impact(s) of human activities on sensitive Gulf Coast environments like PB can be detected through the combination of diatom reconstruction analysis, sedimentology, forensic-style examination of historical reports and witness interviews. [ABSTRACT FROM AUTHOR]

Sedimentation tanks have a vital role in the overall efficiency of solid particles removal in treatment units. Therefore, an in-depth study these tanks is necessary to ensure high quality of water and increasing the system efficiency. In this work, an experimental rectangular sedimentation tank has been operated with and without a baffle to investigate the system behaviour and effectiveness for the reduction of solid particles. Turbid water was prepared using clay, which was collected from the water treatment plant of Al Maqal Port (Iraq), mixed with clear water in a plastic supply tank. Raw and outflow samples were tested against turbidity after plotting a calibration curve between inflow suspended solids versus their corresponding turbidity values. The key objective was to assess the impact of different flow rates, particle concentrations, heights and positions of the baffle on the system efficiency. Findings showed that the tank performance was enhanced significantly (p < 0.05) with the use of a baffle placed at a distance of 0.15 of tank length with height equal to 0.2 of tank depth. Higher removal efficiency (91%) was recorded at a lower flow rate (0.015 dm³·s-1) and higher concentration (1250 mg·dm-3), as the treatment efficiency enhanced by 34% compared with the operation without a baffle. Placing the baffle in the middle of the sedimentation tank produced the worst results. System efficiency for solids removal reduced with increasing baffle height. Further research is required to evaluate the efficiency of an inclined baffle. [ABSTRACT FROM AUTHOR]

Reconstruction of the geological history of orogenic events can be challenging where basins have limited and/or fragmentary preservation. Here, we apply understanding gained from modern analogues to the sedimentological analysis of the succession of Upper Silurian to Lower Devonian Lower Old Red Sandstone (LORS), northern Midland Valley, Scotland, in order to reconstruct the foreland to the Caledonian orogeny. A new depositional model is presented which differs significantly from current understanding. Using facies analysis, grain size distribution and palaeocurrent data a large distributive fluvial system is reconstructed. Three lithofacies and nine sublithofacies are identified, forming fluvial channel and floodplain facies associations. The system was derived from an emerging mountain range in the Caledonian foreland undergoing constant tectonic rejuvenation to produce 9 km of coarse‐grained sediment, exhibiting an overall decrease in thickness towards the west and a large‐scale downstream reduction in grain size. Conglomerate sublithofacies dominate proximal areas in the east where amalgamated fluvial channel facies association is abundant, with a downstream increase in the dominance of floodplain facies. Additionally, observed grain size cyclicity is attributed to a pulsatory tectonic influence. The LORS records the time‐period between the late phases of the Caledonian Orogeny and the onset of post‐orogenic collapse in the mid‐Devonian and the presented model allows improved understanding of the north‐Atlantic Caledonian foreland. [ABSTRACT FROM AUTHOR]

A synthesis has been undertaken based on regionally compiled data from the post early Eocene foreland basin succession of Svalbard. The aim has been to generate an updated depositional model and link this to controlling factors. The more than kilometer thick progradational succession includes the offshore shales of the Gilsonryggen Member of the Frysjaodden Formation, the shallow marine sandstones of the Battfjellet Formation and the predominantly heterolithic Aspelintoppen Formation, together recording the progressive eastwards infill of the foredeep flanking the West Spitsbergen fold‐and‐thrust belt. Here we present a summary of the paleo‐environmental depositional systems across the basin, their facies and regional distribution and link these together in an updated depositional model. The basin‐margin system prograded with an ascending shelf‐edge trajectory in the order of 1°. The basin fill was bipartite, with offset stacked shelf and shelf‐edge deltas, slope clinothems and basin floor fans in the western and deepest part and a simpler architecture of stacked shelf‐deltas in the shallower eastern part. We suggest a foredeep setting governed by flexural loading, likely influenced by buckling, and potentially developing into a wedge top basin in the mature stage of basin filling. High‐subsidence rates probably counteracted eustatic falls with the result that relative sea‐level falls were uncommon. Distance to the source terrain was small and sedimentation rates was temporarily high. Time‐equivalent deposits can be found outbound of Stappen High in the Vestbakken Volcanic Province and the Sørvestsnaget Basin 300 km further south on the Barents Shelf margin. We cannot see any direct evidence of coupling between these more southerly systems and the studied one; southerly diversion of the sediment‐routing, if any, may have taken place beyond the limit of the preserved deposits. [ABSTRACT FROM AUTHOR]

Settling basins are generally used as sediment removal structures in which flow velocity is reduced, resulting in surplus settlement of sediment particles. The accuracy of the available empirical equations for sediment removal efficiency is checked using data available in the literature. The existing relationships of removal efficiency were not found to yield satisfactory results. Therefore, the data were reanalyzed and new models were developed using nonlinear regression and the group method of data handling (GMDH). On the basis of various performance parameters, it was observed that the proposed nonlinear regression model had the highest accuracy compared with other available relationships. It was also observed that the efficiency estimated using the GMDH model (R=0.960 , AAD=14.698 , and RMSE=0.094) was more accurate than that estimated by the regression model (R=0.863 , AAD=30.675 , and RMSE=0.171). Sensitivity analysis indicated that the ratio of particle fall velocity to average flow velocity in the basin was the most effective parameter for sediment removal efficiency. This work will help in quantifying and subsequently improving the management of surplus sediment in canals. [ABSTRACT FROM AUTHOR]

The Kingston Peak Formation of the Pahrump Group in the Death Valley region of the Basin and Range Province, USA, is the thick (over 3 km) mixed siliciclastic–carbonate fill of a long‐lived structurally‐complex Neoproterozoic rift basin and is recognized by some as a key 'climatostratigraphic' succession recording panglacial Snowball Earth events. A facies analysis of the Kingston Peak Formation shows it to be largely composed of 'tectonofacies' which are subaqueous mass flow deposits recording cannibalization of older Pahrump carbonate strata exposed by local faulting. Facies include siltstone, sandstone and conglomerate turbidites, carbonate megabreccias (olistoliths) and related breccias, and interbedded debrites. Secondary facies are thin carbonates and pillowed basalts. Four distinct associations of tectonofacies ('base‐of‐scarp'; FA1, 'mid‐slope'; FA2, 'base‐of‐slope'; FA3, and a 'carbonate margin' association; FA4) reflect the initiation and progradation of deep water clastic wedges at the foot of fault scarps. 'Tectonosequences' record episodes of fault reactivation resulting in substantial increases in accommodation space and water depths, the collapse of fault scarps and consequent downslope mass flow events. Carbonates of FA4 record the cessation of tectonic activity and resulting sediment starvation ending the growth of clastic wedges. Tectonosequences are nested within regionally‐extensive tectono‐stratigraphic units of earlier workers that are hundreds to thousands of metres in thickness, recording the long‐term evolution of the rifted Laurentian continental margin during the protracted breakup of Rodinia. Debrite facies of the Kingston Peak Formation are classically described as ice‐contact glacial deposits recording globally‐correlative panglacials but they result from partial to complete subaqueous mixing of fault‐generated coarse‐grained debris and fine‐grained distal sediment on a slope conditioned by tectonic activity. The sedimentology (tectonofacies) and stratigraphy (tectonosequences) of the Kingston Peak Formation reflect a fundamental control on local sedimentation in the basin by faulting and likely earthquake activity, not by any global glacial climate. [ABSTRACT FROM AUTHOR]

The River Murray Estuary, South Australia exhibits a morphology typical of a wave-dominated estuary and comprises two large, shallow central basin lakes – Lakes Alexandrina and Albert. Contested interpretations of the estuary's limnological history and uncertainty surrounding the sustainability of current basin water usage practice warrant a robust investigation into how the system has evolved. Here we combine lithostratigraphic, geochemical and sedimentological evidence from a transect of sediment cores to reconstruct the sediment infill history of the system. We uncover multiple stages of sediment infill over the history of the system, associated with (1) the low gradient morphology of the estuary and lower river channel, (2) the mid- to late-Holocene sea-level regression and (3) anthropogenic modifications to the fluvio-estuarine system. We show that while estuarine conditions in the system were fully established during the mid-Holocene highstand (~6.4 kyr BP), central basin facies sedimentation was focussed further inland before prograding with the lowering of base level and shifting of tidal influence as sea-level fell. Central basin facies sedimentation within northern Lake Albert occurred from 5.4 to 4.0 cal kyr BP at ~0.25 cm yr-1. The uppermost accumulation of this unit was eroded by continued reduction in base level until sea-level regression concluded at 3.5 cal kyr BP. Barrage and weir installation (1940 CE) re-initiated and expanded central basin facies sedimentation in the estuary (~0.32 cm yr-1). Recently deposited sediments exhibit geochemical markers of increased trophy and more frequent acid sulfate soil acidification, exposing human impacts on the estuary. [ABSTRACT FROM AUTHOR]

The results of studying the material composition of sandy rocks from Cenozoic deposits in the West Sakhalin Terrane are considered. It has been established that sandstones in the terrane correspond to graywackes and petrogenic ("first cycle") rocks. They are characterized by a low maturity degree of the detrital material formed mainly due to the mechanical destruction of source rocks. Paleogeodynamic interpretation of the obtained data suggests that the Paleocene–Pliocene sedimentation occurred directly along the Asian continent margin in a basin associated with large-scale shear dislocations along transform faults. The feeding zone was mainly composed of the following sources: (i) sialic land composed of the granitic-metamorphic and sedimentary rocks; (ii) mature deeply dissected continental-margin arc, where granitoid batholiths at the base were exposed by erosion. The secondary source was represented by fragments of the Sikhote-Alin accretionary prisms involving ophiolites. The U‒Pb isotopic dating of detrital zircons made it possible to establish the main complexes of granitoids that delivered the clastic material to Cenozoic sedimentation basins in the terrane. [ABSTRACT FROM AUTHOR]

In this study, the physicochemical parameters of the river streams of the Agrioune watershed were evaluated by experimental monitoring and surface water quality modelling. The PegOpera Software suite was used to apply the PEGASE model to the Agrioune River/Basin (north-east of Algeria). This model was used to simulate different parameters concentrations, its application on the Agrioune watershed case is one of the first works that are currently being carried out on the semi-arid regions. In addition to low flows, the surface river water quality in these regions is mostly influenced by urban discharges and agricultural activities. Seven parameters are predicted based on the existing distribution of point and diffuse pollution sources, they are compared to available measured values. A significant correlation was obtained between the simulated and the measured values after calibration of some model inputs. Model performance showed good statistical agreements with a Nash-Sutcliffe efficiency (NSe) oscillating between 0.44 and 0.89 and with determination coefficient (R2) varying between 0.66 and 0.94 for the whole studied parameters. The simulation allowed to locate and to distinguish five different river water classes according to Seq-Eau model. Theses quality classes pointed out some river zones with unsatisfactory physicochemical status, and that have to be addressed with priority measures in order to improve their quality. Furthermore, the model was also used to simulate the impact of replacing settling basins by WWTP in the lower part of the Agrioune watershed. The results showed satisfactory reduction of some pollution parameters concentrations. The PEGASE model and the present study may be useful and may constitute a practical tool for managers to simulate several scenarios for improving the water quality in the Agrioune watershed. [ABSTRACT FROM AUTHOR]

Therefore, the HT ht for GMDH is 42. Therefore, each neuron includes six parameters (i.e., { HT ht } in the first series of Table 4 of original paper that should be tuned through the training phase. [Extracted from the article]

Objectives: The Badong-Zigui Basin is located in the west of the Three Gorges area, and it is surrounded by four different tectonic units: With the Xuefengshan thick-soil tectonic belt on the south, the Qinling orogenic belt on the north, the Huangling anticline on the east, and the eastern extension of the Sichuan Basin in the west. The Badong-Zigui basin is a north-south syncline structure, the sediments in the basin are dominated by Late Triassic-Late Turassic argillaceous rocks, and the special tectonic setting causes strong tectonic activities in the basin. Methods: Using a three-dimensional gravity inversion algorithm based on Lagrangian multiplier constraints, the local Bouguer gravity anomaly in Badong-Zigui area is inverted, and the underground three-dimensional density structure of Badong-Zigui and adjacent areas is obtained. Results: The inversion results show that the Zigui Basin is a low-density area compared with the surrounding area. The sedimentation thickness in the east is deeper than that in the west, and the sediment density is lower than that in the west. The small and medium earthquakes in the area are basically 4-12 km underground. Conclusions: The north-south and north-east ancient water flows in the northern edge of the Zigui Basin successively provide sources for the sedimentation and filling of the basin, forming a structure with lower material density and deeper deposits in the eastern part of the basin; low-density materials in the east are transported and accumulated to the west in the basin. At the same time, it is squeezed by the eastward extension of the Sichuan Basin, and it is speculated that there is a tendency of east-west movement and compression in the basin. [ABSTRACT FROM AUTHOR]

The water and sediment separation pertormance of the Vortex Settling Basin ( VSB ) depends on the characteristics of the velocity field. To understand the influence of the opening of the deflector on the flow field, VSBs with the deflector partially pertorated on the non-overflow area entirely perforated and without any openings were tested with Particle Image Velocimetry (PIV) and simulated with a large eddy turbulence model. The results showed that; ① The opening positions did not affect the vortex properties of the VSBs but did affect their strength. The swirl intensity of the entirely pertorated VSB was the smallest, which made it difficult to extract sediment by centrifugal force. ② The VSBs without any openings were partially perorated helped the sediment to be transported along the radial direction, move down and be discharged, but the radial velocity and secondary flow in the entirely perforated VSB were reduced, which caused the sediment to be deposited on the floor. ③ The velocity on the par tially pertorated deflector was the greatest, which could prevent the sediment from depositing on the deflector. Therefore, to red uce the amount of particles deposited on the deflector of the VSB and to ensure a high sediment trapping efficiency, it is better to choose a deflector that is partially pertorated on the non-overflow area. [ABSTRACT FROM AUTHOR]

This paper presents a retrofit for vortex settling basins (VSBs) by perforating the deflector to reduce sediment deposition and thereby lowering VSB failure risks. Experiments were conducted for two retrofitted VSBs with the deflector perforated on the outside overflow area only and the other entirely perforated. The sediment deposition, sediment trapping efficiency, and water abstraction ratio of the retrofitted VSBs were measured and compared with an original VSB with an unperforated deflector. The VSB with a partially perforated deflector exhibited a similar sediment trapping efficiency and water abstraction ratio to the original VSB, with an average reduction over 40% in sediment deposition on the deflector. The VSB with an entirely perforated deflector had a lower sediment trapping efficiency and greater sediment deposition on the deflector. [ABSTRACT FROM AUTHOR]

The presence of a trilobite, assigned to Pagetia cf. edura, from the Coobowie Limestone in the Port Julia-1A drillhole on Yorke Peninsula indicates that sedimentation in the Stansbury Basin, and probably also in the Arrowie Basin, did not terminate until at least the Wuliuan (middle Cambrian, Templetonian). It further indicates that the folding of the Delamerian Orogeny did not commence until at least the Wuliuan (509–504.5 Ma). [ABSTRACT FROM AUTHOR]

Detection and characterization of hidden industrial inflows causing high fluctuations of the inlet load, is a challenging issue pushing plant operators for a cost-effective solution at regional wastewater treatment plants (WWTPs). On the other hand, carbon source of food industrial origin may have a good use at WWTPs facing otherwise inlet carbon source deficiency. In a case study of a regional domestic WWTP receiving seasonally organic carbon-rich discharge from a fruit juice factory, a new method combining on-site measurements and mathematical modelling was developed and successfully applied for estimating the quality and quantity of both industrial influent load and incoming domestic wastewater streams properly. The originally un-staged bioreactor system operated at low dissolved oxygen (low DO) concentration was unable to meet effluent nitrogen requirements with an additional constant risk of encouraging filament growth. A novel screening method based on special sampling campaigns for estimating carbon availability and C:N ratios of influent wastewater streams coming separately from the large catchment area, was developed and applied. Staging of the previously low DO basins into a flexible system containing non-aerated selectors proved to be efficient for enhancing both biological nitrogen removal and sculpturing appropriately settling biomass. [ABSTRACT FROM AUTHOR]

A combined inorganic and organic geochemical study was carried out on marls and mudstones collected from the Lower Miocene Lopare Basin, Bosnia and Herzegovina. A total of 46 samples collected from two boreholes, Pot 1 (depth of 193 m) and Pot 3 (depth of 344 m), showed that element abundances like boron (B), lithium (Li), strontium (Sr), uranium (U), chromium (Cr), nickel (Ni), magnesium (Mg), sodium (Na) and calcium (Ca) are much higher than average than in the upper continental crust (UCC). Chemical composition indicates at least two sources: (i) Mesozoic ophiolites occurring in the north of the investigated area, and (ii) dacito‐andesitic pyroclastics (Mesozoic to Cenozoic). Lopare Basin sedimentation was influenced by strong evaporation resulting in a partly hypersaline lake, which formed during a warm climatic period, probably during the Miocene Climatic Optimum. A brief episode of humid climate conditions resulted in the basin filling‐up and deposition of felsic sediments enriched in thorium (Th). Organic geochemistry shows that the majority of studied sediments contains predominantly immature to marginally mature algal organic matter (OM). The biomarker patterns are generally in agreement with the geological history of the Lopare Basin and inorganic and mineralogical data. Conversely, the molecular distribution of n‐alkanes as reliable climatic and δ‐MTTC as paleosalinity indicators do not support this conclusion. [ABSTRACT FROM AUTHOR]

The Variscan transition from Devonian passive to Carboniferous active margin is recorded in the Upper Devonian stratigraphic succession of the Cantabrian Mountains. The transitional beds contain two tectono-sedimentary phases distinguished by depositional style, and separated by an extensive regional unconformity; the Upper Devonian Unconformity. Phase I contains the Frasnian-lower Famennian shallowing upward clastic wedges. At the initial stage of foreland system evolution, orogenic relief of the approaching fold and thrust belt was low. Erosion products came from the nearby peripheral bulge on the craton side of the system and were deposited in the initial foreland basin. The erosion of the bulge created the Upper Devonian Unconformity. The Phase I succession contains both Devonian palaeogeographical characteristics of a passive margin configuration with a systematic proximal depositional change towards the core of the Cantabrian Zone, as well as indications of the formation of an initial foreland basin, with thick sediment wedges in the outermost rim of the Asturo- Leonese Basin. Phase II contains the thin but widespread upper Famennian-lower Tournaisian succession mantling the unconformity, indicating the transformation from a sediment shedding peripheral bulge area into the initial foreland of the evolving Variscan Orogeny. The Upper Devonian clastic wedges of Phase I are interpreted as the transitional tectonosedimentary environment between the underlying Devonian passive margin stage with extensive stable shelves, and the overlying condensed succession of Phase II. The Upper Devonian Unconformity between the phases marks the fundamental reorganisation of the depositional system to Variscan foreland basin sedimentation. [ABSTRACT FROM AUTHOR]

Based on the data from long sediment cores retrieved by R/V Eltanin (United States) during the 1950s–1960s, Neo- and Eopleistocene lithofacies maps of the southern Pacific Ocean (scale 1 : 20 000 000) and Scotia Sea (scale 1 : 10 000 000) were compiled for the first time. For the Scotia Sea, schemes of isopachites are shown on the respective lithofacies maps. All maps are processed with the volumetric method proposed by A.B. Ronov. The results revealed that accumulation rates of the terrigenous and siliceous sediments increased during the Pleistocene in both sedimentation basins due to neotectonic activity in the Antarctic Peninsula, which enhanced fluxes of not only terrigenous matter but also nutrients delivered by melted waters to the photosynthesis zone via vertical circulation. [ABSTRACT FROM AUTHOR]

A long-standing goal of sedimentary geoscience is to understand how tectonic and climatic changes are reflected in basin fill. Here, we use 14 numerical models of continental-scale sediment-routing systems spanning millions of years to investigate the responses of sediment supply and basin sedimentation to changes in uplift and precipitation in the source area. We also investigate the extent to which these signals can be altered by relative sea level (the sum of subsidence and eustasy). In cases of constant relative sea level, sediment supply and margin progradation have similar responses because nearly all of the sediment is transported beyond the coastal plain and continental shelf to the basin margin. Thus, margin progradation can be used as a proxy for sediment supply. However, changes in uplift and precipitation result in different erosional patterns in the source area and different basin-margin depositional patterns. Changes in uplift result in gradual (over several million years) adjustment to new steady states of source-area erosion and margin progradation, whereas changes in precipitation result in abrupt changes in erosion and progradation followed by a return to the initial steady states. In cases of changing relative sea level, sediment storage on the shelf attenuates signals of uplift, but signals of precipitation change can be interpreted in the basin-margin record because climate-induced sediment supply changes are large enough to influence margin progradation. Understanding the relationship between sediment supply and basin-margin progradation, and their linked responses to forcings, improves our ability to interpret signals of environmental change in the stratigraphic record. [ABSTRACT FROM AUTHOR]

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The Ulleung Basin, East Sea/Japan Sea, is a Neogene back‐arc basin and occupies a tectonically crucial zone under the influence of relative motions between Eurasian, Pacific and Philippine Sea plates. However, the link between tectonics and sedimentation remains poorly understood in the back‐arc Ulleung Basin, as it does in many other back‐arc basins as well, because of a paucity of seismic data and controversy over the tectonic history of the basin. This paper presents an integrated tectonostratigraphic and sedimentary evolution in the deepwater Ulleung Basin using 2D multichannel seismic reflection data. The sedimentary succession within the deepwater Ulleung Basin is divided into four second‐order seismic megasequences (MS1 to MS4). Detailed seismic stratigraphy interpretation of the four megasequences suggests the depositional history of the deepwater Ulleung Basin occurred in four stages, controlled by tectonic movement, volcanism, and sea‐level fluctuations. In Stage 1 (late Oligocene through early Miocene), syn‐rift sediment supplied to the basin was restricted to the southern base‐of‐slope, whereas the northern distal part of the basin was dominated by volcanic sills and lava flows derived from initial rifting‐related volcanism. In Stage 2 (late early Miocene through middle Miocene), volcanic extrusion occurred through post‐rift, chain volcanism in the earliest time, followed by hemipelagic and turbidite sedimentation in a quiescent open marine setting. In Stage 3 (late middle Miocene through late Miocene), compressional activity was predominant throughout the Ulleung Basin, resulting in regional uplift and sub‐aerial erosion/denudation of the southern shelf of the basin, which provided enormous volumes of sediment into the basin through mass transport processes. In Stage 4 (early Pliocene through present), although the degree of tectonic stress decreased significantly, mass movement was still generated by sea‐level fluctuations as well as compressional tectonic movement, resulting in stacked mass transport deposits along the southern basin margin. We propose a new depositional history model for the deepwater Ulleung Basin and provide a window into understanding how tectonic, volcanic and eustatic interactions control sedimentation in back‐arc basins. [ABSTRACT FROM AUTHOR]

The Papaghni sub-basin of the Cuddapah basin is an arcuate NW-SE trending intracratonic basin, stretching from Kurnool in the NW to Guvvalacheruvu in the SE, in southern peninsular India. Despite of large number of researches, an understanding of the evolution of the basin is still elusive. The sub-basin preserves records of repeated opening and closing of Paleoproterozoic rifts along the zone of NW-SE trending axis in the East Dharwar craton. Present study was carried out along the southwestern margin of the Papaghni sub-basin, in and around Tadpatri-Gooty-Dhone area, where the successive litho-units are represented by two major unconformity-bound sequences. Each of these sequences are characterized by a distinctive set of litho-assemblage, deposited under diverse tectonic environments with highly variable modes and tempos of sedimentation in an extensional basin. The basin initiated at about 2 Ga and shortly evolved into a shallow sea, with development of wide siliciclastic shelf in an open marine condition, the Gulcheru Formation. Gradually, with time the siliciclastic shelf was replaced by an extensive stromatolitic carbonate platform, the Vempalle Formation. Dedicated fieldwork exemplifies that the initial basin-fill is characterized largely by several cycles of simple, but amalgamated and stacked fanglomerates (alluvial fan to fan-delta) systems developed from several single stream breaches onto the proximal setting of the basin, in a syn-rift setting. These fanglomerates display a fining upward sequence, which progressively passes up to high-energy coastal, tide-storm dominated shelf environments of post-rift setting. This study justifies the subdivision of the Gulcheru Formation into two formal lithostratigraphic members, the Daditota Member and the Karvipalle Member. The Daditota Member directly overlies the granitoid basement and grades upward to Karvipalle Member. Karvipalle Member, comprising predominantly of medium to finegrained, reddish brown and white quartz arenites of stable shelf deposits, distinctly differs from the conglomerate and very coarsegrained mass-flow dominated deposits of the Daditota Member. The Vempalle Formation overlies the Gulcheru Formation with a gradational contact and consists of stromatolitic dolomite, oolite and shale, developed in a ramp type carbonate platform setting. Gradual transition from siliciclastic to carbonate sequence points to passive margin setting developed during the breakup of the supercontinent Kenorland. Disposition of proximal to distal sequences and northeastern, eastern and southeastern paleocurrent of the sequences advocate a NW-SE shoreline and eastern paleoslope of the basin. [ABSTRACT FROM AUTHOR]

The characterization of sludge settling is important in determining the operating performance of the secondary clarifier and also evaluating the purification efficiency of wastewater treatment plants. Many models have been proposed to explain the activities of settling velocity and illustrating the relationship between settleability characteristics. The aim of this research was to present a model for the settling velocity as a function of the stirred specific volume index at 3.5 g/L (SSVI3.5), based on the Vesilind function, the solids flux theory, and the experimental data. Using this model gives an important performance improvement after calibration of the different settleability parameters. Practitioner points: Batch settling tests are some of the most interesting source of information to determine the sedimentation velocities and their characteristics.The modeling as an optimum operation of wastewater treatment plants is widely used for design, optimization, and management of installations.The characterization of sludge settling is important in determining the operating performance of the secondary clarifier.The characterization of sludge settling is necessary to evaluate the purification efficiency of wastewater treatment plants. [ABSTRACT FROM AUTHOR]

In this study, we developed a distributed rainfall-runoff and sedimentation model based on one-dimensional kinematic wave equations. Physically-based rainfall-runoff and erosion-sediment processes were coupled and solved for each spatial grid, whilst the spatially distributed grids were connected to each other to allow for space-and-time movements of water and sediment. The model was applied to the Akatani River basin of the Chikugo River in Kyushu, Japan using a 10 m high-resolution digital elevation model and eXtended RAdar Information Network (XRAIN) data as a time-and-space distributed rainfall input of the northern Kyushu heavy rainfall event in July 2017. Our results indicate that the rainfall-runoff hydrograph and sediment flow results are in agreement with the collected field data, and elevation of the river bed after the disaster was successfully reproduced by applying a sediment theory to estimate river bed variation. In addition, we found that sediment transport results are sensitive to model spatial resolution. Our simulation model is intended for use with basins that feature steep slopes and are prone to erosion and shear strength reduction after heavy rainfall events. Hence, this model can be applied to give early warnings by identifying critical erosional areas during forecasted heavy rainfall events. [ABSTRACT FROM AUTHOR]

Central Asia is a large-scale source of dust transport, but it also held a prominent changing hydrological system during the Quaternary. A 223 m long sediment core (GN200) was recovered from the Ejina Basin (synonymously Gaxun Nur Basin) in NW China to reconstruct the main modes of water availability in the area during the Quaternary. The core was drilled from the Heihe alluvial fan, one of the world's largest alluvial fans, which covers a part of the Gobi Desert. Grain-size distributions supported by endmember modelling analyses, geochemical–mineralogical compositions (based on XRF and XRD measurements), and bioindicator data (ostracods, gastropods, pollen and non-pollen palynomorphs, and n -alkanes with leaf-wax δD) are used to infer the main transport processes and related environmental changes during the Pleistocene. Magnetostratigraphy supported by radionuclide dating provides the age model. Grain-size endmembers indicate that lake, playa (sheetflood), fluvial, and aeolian dynamics are the major factors influencing sedimentation in the Ejina Basin. Core GN200 reached the pre-Quaternary quartz- and plagioclase-rich "Red Clay" formation and reworked material derived from it in the core bottom. This part is overlain by silt-dominated sediments between 217 and 110 m core depth, which represent a period of lacustrine and playa-lacustrine sedimentation that presumably formed within an endorheic basin. The upper core half between 110 and 0 m is composed of mainly silty to sandy sediments derived from the Heihe that have accumulated in a giant sediment fan until modern time. Apart from the transition from a siltier to a sandier environment with frequent switches between sediment types upcore, the clay mineral fraction is indicative of different environments. Mixed-layer clay minerals (chlorite/smectite) are increased in the basal Red Clay and reworked sediments, smectite is indicative of lacustrine-playa deposits, and increased chlorite content is characteristic of the Heihe river deposits. The sediment succession in core GN200 based on the detrital proxy interpretation demonstrates that lake-playa sedimentation in the Ejina Basin has been disrupted likely due to tectonic events in the southern part of the catchment around 1 Ma. At this time Heihe broke through from the Hexi Corridor through the Heli Shan ridge into the northern Ejina Basin. This initiated the alluvial fan progradation into the Ejina Basin. Presently the sediment bulge repels the diminishing lacustrine environment further north. In this sense, the uplift of the hinterland served as a tipping element that triggered landscape transformation in the northern Tibetan foreland (i.e. the Hexi Corridor) and further on in the adjacent northern intracontinental Ejina Basin. The onset of alluvial fan formation coincides with increased sedimentation rates on the Chinese Loess Plateau, suggesting that the Heihe alluvial fan may have served as a prominent upwind sediment source for it. [ABSTRACT FROM AUTHOR]

The lungfishes, or Dipnoi, form a depauperate clade of sarcopterygian fishes living today in the freshwater systems of eastern Australia, Africa, and South America. It is reminiscent of the equivalent bone in I F. martini i , except that in the latter species the anterior portion of the ossification corresponds to the widest part of the bone, whereas in I F. annekempae i sp. nov. the anterior portion is significantly narrower than the posterior portion. In this model of I F. jurassicus i , the bone shows no anteroventral extension and it is unclear how the mandible articulates with the skull (in I Neoceratodus i , the quadrate is cartilaginous and occurs as an outgrowth from the process of the posterior bone of the lateral series, and the situation was likely similar in most extinct post-Devonian lungfishes; Kemp, [9]). Abbreviations: a.m.b, anterior bone of the medial series; a.ml.b, anterior bone of the mediolateral series; p.l.b, posterior bone of the lateral series; p.m.b, posterior bone of the medial series; p.ml.b, posterior bone of the mediolateral series; x, X bone. [Extracted from the article]

The early Permian Barakar coal measures Formation of Gondwana Supergroup in the Godavari basin comprise siliciclastic fluvial facies of passive continental margin. The lithofacies relationship and their sequences are analyzed quantitatively using embedded Markov Chain analysis along with improved binomial probability method. Summarized lithofacies sequence show the following order: (CGSD= Matrix supported conglomerate, gritty to pebbly/coarse-grained tabular and trough cross bedded sandstones)→(MGSD= Medium grained trough and planar cross bedded sandstones)→(FGSD= Fine-grained parallel and ripple drift cross-laminated sandstones)→(SH= Shale/inter-bedded sandstone-shale and gray shale)→(C=coal/shaly coal and carbonaceous shale)→(CGSD= Matrix supported conglomerate, gritty to pebbly/coarse-grained planar and trough bedded sandstones). These repetitive cycles accumulated in a low sinuosity, high gradient braided streams which became moderately sinuous at places. The lithofacies relationships showing fining upward tendency suggest a progressive upward decline in current competency. The sequence is considered as the classical example of a sand dominated braided river. The lateral changes in lithofacies association indicate shifting of sub-environments from stream channel, overbank levee and peat forming back swamp to flood plains of fluvial system. It is suggested that the channel wandering along with differential intra-basinal tectonism and subsidence controlled cyclic repetition during early Permian sedimentation in the Godavari basin. [ABSTRACT FROM AUTHOR]

The Siang valley in the eastern part of Arunachal Himalaya contains Paleocene–Eocene sediments of Yinkiong Group along with the Abor volcanic exposed in a wide lateral extent in the middle and lower Siang valleys. Based on available geologic data and detail geologic mapping present study proposes a new evolution model of the basin in the context of India–Asia collision tectonics. Integration of the field data on the disposition of different litho units from Pasighat (south) to Tuting (north) along the Siang valley and in the Mishmi block, helped us to constrain several major thrust fault and strike-slip faults in the area showing dextral and sinistral senses. Some of these faults are conjugate. It is postulated that during the early Paleocene, the Indian Plate collided with the Eurasian Plate and this collision resulted in the breakage of an edge of the Indian Plate along its northeastern extremity. This broken edge rotated towards the Burmese Plate and eventually formed a rift basin that led to the ingress of the Tethys Sea where sedimentation along with syn-sedimentary volcanism took place. The sedimentation in the basin continued throughout the Paleocene–Eocene time. The absence of rocks younger than Yinkiong Group indicates that this basin was closed at the end of the Eocene. The development of a highly folded sequence along the Siang valley in response to north south-directed compression can be constrained due to subsequent India‒Asia collision. The broken edge of the Indian Plate and western part of the Burmese Plate amalgamated through Tuting–Tidding suture. This Indo-Burmese amalgamated part of the Mishmi block thrusted over the Paleocene–Eocene sequence from the east. The continued NNW ward movement of the Mishmi block resulted in the swinging of the MCT towards the northeastern direction. On the other hand, the overriding of the Himalayan metamorphic belt along the Tidding Thrust was intense, leaving only a narrow exposure of garnetiferous graphite-schist and garnetiferous amphibolites as slivers of the ophiolite package. The Lesser Himalayan sequences of the Mishmi block overrode the frontal molasses basin in many places and are in direct contact with the Brahmaputra alluvium in the southeastern part along the Lohit and Dibang valleys. The Lesser Himalayan sequence also overrode the Paleocene–Eocene sequence from the western direction showing significant occurrences in the Boleng and Bomdo area of the Siang valley. [ABSTRACT FROM AUTHOR]

Sedimentation basin is an important component of every water treatment process. In order to improve the sedimentation efficiency (SE) of rectangular sedimentation basins, many researchers have proposed various methods. Among the suggested methods, the change of the geometry with installation of baffle in the basin floor is simple and completely economic. In this research, the hydraulic characteristics of the flow with various baffle configurations in the basin floor have been evaluated and the best geometry of the baffle has been presented. The agreement between numerical and experimental results was good. The results showed that the flow in the sedimentation basin is strongly influenced by the baffle. Also, the baffles installed with lower height and closer to the basin inlet and baffles with high height and far from the basin inlet have the greatest effect on the SE. [ABSTRACT FROM AUTHOR]

One of the most effective ways to dissipate the destructive energy of water downstream of a flow control structure is the interference of water with air (such as a vertical drop). In this study, the hydraulic parameters of a vertical drop equipped with dual horizontal screens and with the subcritical upstream flow were investigated. Experiments were performed for two drop heights, two porosities, three relative distances between the screens, and a relative critical depth that was varied from 0.077 to 0.242. The results revealed that the relative distance between the screens does not affect the relative depth and downstream residual energy. On the other hand, increasing the relative length of the drop caused a decrease in the relative depth. Also, for a vertical drop equipped with a type 1 settling basin, the relative downstream depth decreased by more than 48%. The normal residual downstream energy and the relative total length of the drop are also decreased. The results also reveal that the use of dual horizontal screens transformed the regime of flow from super- to subcritical downstream of the drop. [ABSTRACT FROM AUTHOR]

The separation process of water treatment such as coagulation/flocculation separates various particle matters from water using specific gravity differences. Among several particle separation technologies, the ballasted flocculation (BF) process has recently been proposed to cope with water quality changes due to climate change. Each technology of the BF process is designed to maximize the particle removal efficiency of the whole process. The removal efficiency of the separation process is affected by not only floc characteristics but also hydraulic characteristics, resulting in the short-circuiting flow, dead-zone due to the density difference formed by temperature and specific gravity of the liquid, and the turbulence caused by the shape of the inlet and outlet. The circular lamellar settling tank can reduce a short-circuiting flow and dead-zone. In addition, it can reduce the settling distance and the settling time of suspended solid, while the increased effective sedimentation area can increase the sedimentation efficiency per unit volume. However, if the lamellar plate is designed improperly, the flocs to be removed inevitably release to effluent or accumulate on the plate, which affects the water quality negatively. Therefore, in this study, to confirm the removal efficiency of ballasted flocs according to the angle of the lamellar plate in a circular lamellar settling tank, we simulate the effect of changing the plate angle using computational fluid dynamics (CFD). CFD simulation was conducted to estimate the particle inflow ratio into the lamellar module, the particle removal efficiency of the lamellar module, and the whole particle removal efficiency of the circular lamellar settling tank. The particle inflow ratio into the lamellar module is the smallest at 60° of lamellar plate, while the specific gravity and the size of particles are smaller. This phenomenon shows that the sedimentation force by gravity is predominant. The particle removal efficiency of the lamellar module was also the highest at 60° of lamellar plate. [ABSTRACT FROM AUTHOR]

This case study aims to identify the cubic capacity and geometry of the geological body of silt–organic sediments in the environment of a former gravel pit situated in a drainless depression of the alluvium of the Čierna voda River. It is located in the well-known geotourism locality of Slnečné Jazera in Senec, in the SW of Slovakia. To identify the body, electrical resistivity tomography was combined with the use of sonar. The research shows that this approach is appropriate for a number of activities that are subjects of engineering-geological investigations. The cubic capacity and geometry of specific aqueous engineering-geological environments must be determined in connection with the need for the management, control, quantification and extraction of selected sedimentary bodies. In addition, the management of sustainable development of reservoirs, sedimentation basins, industrial ponds, settling pits and natural pools for recreation (the subject of the case study) is important to control the limit amounts of sediments in such environments. The results of this study may be applied in analogous engineering-geological conditions. The drainless depression Slnečné Jazera contained a body of silt–organic sediments amounting to 23 000 m3 (41 Olympic-size pools of 25 m × 12.5 m × 1.8 m). The maximum thickness of the bottom sediments was about 6.3 m on the alluvium with an articulated morphology owing to the submerged digging of gravel. The proposed approach improved the control of extraction of the sedimentary body and optimized the engineering-geological conditions in this geotourism locality. [ABSTRACT FROM AUTHOR]

Coastal cities in tropical areas are often low-lying and vulnerable to the effects of flooding and storms. San Juan, Puerto Rico, is a good example of this. It is built around a lagoon-channel complex called the San Juan Bay Estuary (SJBE). A critical channel in the estuary, the Caño Martín Peña, has filled in and now frequently floods the surrounding communities with sewage-enriched waters, causing a series of human health and ecological problems. Sediment core analyses indicate that portions of the SJBE now function as settling basins. High urban and sewage runoff to the Caño contributes nitrogen (N), but stable isotope and sediment nutrient analyses indicate that this runoff may also enhance conditions for coupled sulfate reduction-nitrogen fixation. The amount of 'new' bioavailable N created from inert atmospheric N2 gas may meet or exceed that from the runoff into the Caño Martín Peña. The ecological consequences of this appear to extend beyond the ponded channel, potentially contributing to the poor water quality of the SJBE, greater than contaminated runoff alone. [ABSTRACT FROM AUTHOR]