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Radio Echo Sounding (RES) surveys conducted in May 2010 and April 2011 revealed a 2 km2 flat area with increased bed reflectivity at the base of Isunnguata Sermia at the western margin of the Greenland Ice Sheet. This flat reflector was located within a localized subglacial hydraulic potential (hydropotential) minimum, as part of a complex and elongated trough system. By analogy with comparable features in Antarctica, the initial interpretation of such a feature was a potential subglacial lake. In September 2013 a co‐located seismic survey revealed a 1,750 m by 540 and 37 m thick stratified lens‐shaped bedform at the base of a subglacial trough system. Amplitude Versus Angle (AVA) analysis yields a derived reflection coefficient R = 0.09 ± 0.14 indicative of consolidated sediments possibly overlain by dilatant till. The bed and flank on the northern side of the trough consist of unconsolidated, possibly water‐bearing sediments with R = −0.10 ± 0.08, whereas on the southern side it consists of more consolidated material. We interpret the trough as a key component of the wider subglacial drainage network, for which the sediments on its northern side act as a localized water‐storage reservoir. Given the observation of seasonally forming and rapidly draining supraglacial meltwater lakes in this area, we interpret the lens‐shaped bedform as deposited by episodically ponding meltwater within the subglacial trough system. Our results highlight the importance of transient subglacial hydrological and sedimentological processes such as drainage events for the interaction of ice sheets and their substrates, to understand ice dynamics in a warming climate. Plain Language Summary: A ground based radar survey in West Greenland showed an unusually flat, highly reflective zone in an otherwise rough bed suggesting a possible subglacial lake beneath the ice. The highly reflective zone was part of a drainage system transporting meltwater under the ice sheet. We performed a detailed seismic survey across the area which, unlike radar signals, has the advantage of penetrating through the overlying ice into any rock, sediments and water below it. Analysis of our reflection data reveal that the flat area was in fact an elongated lens‐shaped bedform consisting of layered (stratified) sediments. However at a larger angle of incidence, analysis showed the bedform is possibly overlain by a thin layer of water‐bearing sediments likely saturated by ponding water. Our interpretation is that episodically draining meltwater from upstream is locally accumulating beneath the ice sheet at this locality, thereby depositing the lens‐shaped bedform over many melt seasons. Key Points: Seismic data show that a subglacial lake implied by high reflectivity in radar data is in fact a lens‐shaped sediment bedformSeismic reflectivity analysis suggests the lens‐shaped bedform is possibly overlain by a thin layer of water‐bearing sedimentsThe subglacial bedform is stratified and likely deposited through episodically ponding of upstream derived meltwater [ABSTRACT FROM AUTHOR]

Irrigation water requirement for irrigation for land preparation is the highest water requirement in rice cultivation therefore it was essential to determine it based on recent condition in order to support the irrigation modernization. This research aimed to determine the irrigation requirement and tillage specific drafts based for various water ponding level in rice field as well as to determine parameters of irrigation requirement for land preparation to support irrigation modernization. Determination of irrigation water requirement is computed based on equation developed by Van de Goor and Zijlstra (1968) with variation of water volume supplied for saturation and ponding level. Variation of water supplied during land preparation resulted in the variation of tillage specific drafts according to empirical formula developed by Kisu (1972). Water level ponding of 0 mm, 5 mm, 30 mm, and 74 mm resulted in water requirements for land preparation (Project Water Requirement/PWR) of 112 mm, 122 mm, 139 mm, and 198 mm, respectively. The mentioned water ponding level resulted in the tillage specific draft of 1.131 kg/cm2, 1.101 kg/cm2, 0.886 kg/cm2, and 0.954 kg/cm2, respectively. The thicker water ponding in the rice field, the more water requirement for land preparation, but the less energy needed for tillage. Recommended irrigation requirement for land preparation was 139 mm with 15-day duration of land preparation.

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In the last decades, various test methods have been developed to evaluate the resistance of concrete against chloride penetration. This study investigated twelve types of concrete to determine which test method is reliable for ranking concretes. The concrete evaluation included different water to binder ratios (w/b) of 0.4, 0.45, and 0.50 with and without supplementary cementitious materials (SCMs), zeolite, and silica fume. The test methods used included the rapid chloride permeability test (RCPT), rapid chloride migration test (RCMT), salt ponding test (chloride profile), and bulk electrical resistivity. The test results revealed that all test methods are appropriate for diagnosing chloride penetration resistance grading of concrete and can be used as a performance indicator. This result indicates a proper correlation between the results of the tests. The finding showed that the limitation on the w/b ratio is inadequate to ensure high chloride penetration resistance, and the lowest chloride penetration was recorded for concrete with binary SCMs zeolite and silica fume. Results revealed that the increase in concrete electrical resistivity due to the replacement of pozzolans is much more significant than the w/b ratio effect. Also, it was found that electrical resistance is a function of pore structure and chemical composition of concrete pores, which is used as a performance index to save testing time and cost effectiveness. [ABSTRACT FROM AUTHOR]

Beavers strongly impact hydrology and ecosystems through their widespread dam building that creates ponds and wetlands. Monitoring the relative abundance of beavers and their waterbodies is needed to assess these effects and factors influencing population levels. However, the ability to do this over vast, remote regions is limited with conventional aerial or field-based surveying. To address this challenge, we developed a satellite remote sensing method to track beaver ponding changes over multiple decades and applied it to a 5127 km ^2 region of the coastal Hudson Bay Lowlands in Manitoba, Canada. Annual, sub-pixel surface water mapping using 30 m resolution Landsat satellite data, combined with a spatial database of beaver dams, permitted the mapping of 37 year (1985–2021) beaver ponding dynamics. We identified 1714 beaver dams and 1085 beaver pond complexes covering 31 km ^2 , indicating that beavers have an important influence on stream hydrology in this high subarctic landscape. The total area of ponding decreased by 53% from 1986–1989 and by 80% by 1995, and then gradually recovered to initial levels by 2015. The early, steep drop in beaver ponding corresponded to a 13% decline in regional surface water area, while a similar wetness decline during 2015–2018 resulted in little change in beaver ponding. We suggest that strong beaver ponding dynamics were likely caused by the interaction between streamflow levels and beaver populations living near their northern range limit and cold tolerance. The pond mapping method can be applied to other regions if the long-term distribution of beaver dams is known, and ponds are large enough to be identified using a Landsat sub-pixel approach.

• A Simple Analytical Method (SAM) was applied to estimate areas under flooding risk. • Antecedent soil moisture condition was expressed quantitatively using soil and rainfall data. • When antecedent water content is unknown, SAM allows a first estimate. • Our results suggest that SAM can be used as part of early warning systems of flood risks. The study of runoff formation in semiarid regions relies generally on the solution of Richards equations using numerical approaches such as those provided by Hydrus-1D. We demonstrate here that a Simple Analytical Method (SAM) could be easily applied to estimate areas under flooding risk, under different soil and rainfall conditions, without the need to run burdensome numerical models. The impact of antecedent soil moisture condition was expressed quantitatively, conferring to SAM a predictive capability based on a-priori information on soil properties, rainfall characteristics, and initial conditions. The SAM was applied to the Shikma catchment, in the center of Israel, to illustrate its capability to estimate the spatial distribution of time of runoff occurrence and runoff coefficient for a prescribed rainfall event. The results suggest that SAM can be used as part of early warning systems of flood risks. Radars, carried by satellites and drones, can be used to provide refined data on rainfall intensity and soil surface initial conditions. SAM could be then coupled with these remotely sensed data to improve runoff initiation and accumulation estimates, thus reducing the time interval required to reach operational decisions regarding potential floods and inundations, and related water erosion hazards. [ABSTRACT FROM AUTHOR]

The Ephesus fan is a giant channel-lobe complex that extends across 460 km2 in the lower structured slope of the West Orphan Basin, offshore Newfoundland, Canada. Based on biostratigraphic dating of offset wells, the fan was likely deposited during the Oligocene. High resolution 3D seismic data reveal that the fan overlies a succession of mass transport deposits that initially created a flatter topographic surface, with later slumping events building elongated ridges. Subsequent high density turbidity currents coursed into the area through a single feeder channel, depositing as lobes onto the flatter area via a network of distributary channels. The lobes were circumferentially ponded and internally compartmentalized by the slump ridges, and the ponding forced the fan to assume its unique, 46 km-wide shape. Distributary channels were initially directed to the south side of the fan, due to the higher relief of the mass transport deposits to the north. After the infill of the accommodation space to the south, subsequent sediment input levelled the remaining rugose topography, and some distributary channels were able to avulse north. Throughout deposition of the fan, distributary channels also continued down-dip from the lobe complex, indicating some sediment bypass continuing down the lower slope. Overlying laminated mudrock displays pervasive polygonal faulting, signaling dewatering processes and the end of deposition by muddy submarine landslides and high density turbidity currents. • The Ephesus fan is a channel-lobe complex that extends across 460 km2 in the lower structured slope of West Orphan Basin. • Based on biostratigraphic dating of offset wells, the fan was likely deposited during the Oligocene. • The MTCs flattened the lower slope and formed a series of ridges, which ponded the fan into its unique, wide shape. • Overlying mudrock displays polygonal faults, signaling dewatering and the end of MTC and high density turbidite deposition. [ABSTRACT FROM AUTHOR]

• Multi-type data characterized the disturbance of the China–Russia Crude Oil Pipeline (CRCOP) on the permafrost environment. • Mapped the development of the talik around pipelines under the influence of multiple factors. • Permafrost thawing along the CRCOP caused topographic reshaping and the regular distribution of ponds. • Synergistic changes of underground permafrost and surface features. Engineering activities in permafrost regions have a major impact on the local permafrost environment. The construction and operation of the China-Russia Crude Oil Pipeline (CRCOP) have changed the surface conditions and the soil's thermal state. However, the response of the permafrost environment to CRCOP is less studied. This article carries out ground temperature monitoring, ground surface deformation (GSD) and pipeline deformation observations, electrical resistivity tomography (ERT) measurements, and unmanned aerial vehicle (UAV) surveys to study permafrost thawing, talik development, topographic change, and pond distribution. The results indicated that the oil temperature has increased yearly and the permafrost around the pipeline has degraded quickly. The artificial permafrost table has decreased at a rate of 0.68 m/a at a location 2 m away from the center of the pipeline, and reached −11.4 m deep by 2022. The talik around CRCOP I was larger than that around CRCOP II and the two taliks were gradually approaching each other. Permafrost-thawing-induced pipeline subsidence and surface settlement have led to thermokarst depressions and water accumulation. The sinking rates of CRCOP I and II are approximately 0.2 m/a and 0.45 m/a, respectively. The ground surface settlement rate on the right-of-way of the pipeline (on-ROW) is about 5.49 cm/a. Settlement rate in ponding areas is 8.18 cm/a, significantly larger than 4.81 cm/a in non-ponding areas. The ponding area on-ROW accounts for 67.4 % and it on CRCOP I is larger than that on CRCOP II. Pipeline construction, high oil temperature, and permafrost thawing have led to the development of geohazards, which have potential to be worsen under the influence of fires, climate warming, and human activities. Multi-type data provides ground verification for satellite images to extract deformation and ponding information along pipelines, and provides a scientific basis for assessing the thermal impact of pipelines and geohazard development. [ABSTRACT FROM AUTHOR]

• Rainfall/runoff relationship is studied using simulated rainstorms time series. • The impact of rainfall intensity and antecedent soil moisture on runoff formation is analyzed and quantified. • Rainfall intensification and dry spells increase lead to the reduction of potential runoff. • Increase in the variance of storm intensity generates more runoff. • Negative skewness in storm structure leads to early runoff occurrence while zero skewness leads to more runoff. Rainfall intensity and antecedent soil moisture are key variables affecting the initiation and accumulation of runoff, and therefore, impact on the occurence flood events. We used time series of rainfall intensities characterizing rainstorms with different mean, standard deviation, and skewness to simulate runoff response of a sealed loamy soil profile under various initial soil moisture conditions. We found that shifting from wet to dry initial soil moisture leads to a 300 % increase in ponding time and a 350 % decrease in total runoff. Intense rainfall events catalyze runoff development and runoff occurs earlier with increasing mean, maximum intensity, and variance of rainfall. Higher variance in intra-event storm-intensity temporal distribution yields more runoff. Earlier runoff formation aligned with negatively skewed storm structures, but largest cumulative runoff resulted from storms displaying near-zero skewness values. The combination between rainfall intensification and extended dry periods between storms might reduce potential runoff. These insights improve our understanding of anticipated impacts of climate variations on floods and may also contribute to ecosystem health evaluations, and bolster predictive capabilities of surface processes. [ABSTRACT FROM AUTHOR]

The ponding on an inflated membrane tube is studied. Membrane tubes have the advantage of zero leakage and ease of transportation and set-up. A novel related problem is the membrane trough which can be used to contain water and does not need anchoring. These problems depend on two non-dimensional parameters which characterize membrane tension and pressure. Perturbation solutions to second order are found for shallow ponding, and compare well with those of exact numerical integration. Tables for the pertinent parameters are constructed and cross section geometries are found. This research illustrates the interaction of membrane structure, pressure load, and hydrostatics. [ABSTRACT FROM AUTHOR]

The improvised construction techniques and utilization of industrial wastes in manufacturing concrete play a major role in sustainability. The artificially manufactured aggregates are gaining importance in the present era. The use of fibers as secondary reinforcement is greatly pronounced. Sintered fly ash aggregate concrete and normal aggregate concrete with and without basalt fiber with 28 days compressive strength of 30 Mpa were cast and tested. The stress–strain curve of the lightweight concrete has a lower modulus of elasticity when compared with the normal aggregate concrete. A simple linear relationship has been developed between the mechanical properties using regression analysis. The water absorption and void ratio had a direct relationship with the sorptivity and ponding of concrete. The strength and durability aspects of the lightweight aggregate concrete had better agreement with the requirements of the structural lightweight concrete. Strict adherence to codal provisions with respect to strength and durability can be made for improvised behavior. [ABSTRACT FROM AUTHOR]

Roof collapses due to ponding instability are among the most frequent structural failures. Although methods of design for other types of instability have evolved and improved with computational advances, the most commonly used method of assessing ponding instability has been updated minimally since it was developed over 50 years ago. Newer methods of design for ponding have been proposed, but they lack independent verification of their ability to assess the strength of roofs and to provide a sufficient level of reliability. An advanced analysis approach capable of capturing material and geometric nonlinearity, as well as accumulation of water caused by deflection, was developed for roofs consisting of steel beams on stiff supports. The new analysis approach generates data against which the various methods of design for ponding can be benchmarked. These comparisons showed that methods of design based on elastic analysis are capable of accurately capturing the strength of structural steel roofs subjected to ponding load if a reduction factor of 0.8 is applied to the stiffness of the structure. In addition, a reliability analysis using Monte Carlo simulation showed that the methods of design for ponding can achieve a target reliability index consistent with design for other loading conditions. The results provide new insights into the behavior of roofs subjected to ponding loads and enable the use of new design methods for ponding that are more broadly applicable, comprehensive, and consistent with current methods of strength evaluation. [ABSTRACT FROM AUTHOR]

Salt marshes are valuable ecosystems, and there is concern that increases in the rate of sea level rise along with anthropogenic activities are leading to the loss of vegetated habitat. The area of vegetated marsh can change not only through advance and retreat of the open fetch edge, but also due to channel widening and contracting, formation and drainage of interior ponds, formation and revegetation of interior mud flats, and marsh migration onto upland areas, each of which is influenced by different processes. This study used historical aerial photographs to measure changes in the extent of vegetated marsh over approximately 70 years at study marshes located in three long-term ecological research (LTER) sites along the US East coast: Georgia Coastal Ecosystems (GCE), Virginia Coast Reserve (VCR), and Plum Island Ecosystems (PIE). Marsh features were categorized into vegetated marsh, ponds, interior mud flats, and channels for three time periods at each site. The three sites showed different patterns of change in vegetated marsh extent over time. At the GCE study site, losses in vegetated marsh, which were primarily due to channel widening, were largely offset by channel contraction in other areas, such that there was little to no net change over the study period. The study marsh at VCR experienced extensive vegetated marsh loss to interior mud flat expansion, which occurred largely in low-lying areas. However, this loss was counterbalanced by marsh gain due to migration onto the upland, resulting in a net increase in vegetated marsh area over time. Vegetated marsh at PIE decreased over time due to losses from ponding, channel widening, and erosion at the open fetch marsh edge. Digital elevation models revealed that the vegetated areas of the three marshes were positioned at differing elevations relative to the tidal frame, with PIE at the highest and VCR at the lowest elevation. Understanding the patterns of vegetation loss and gain at a given site provides insight into what factors are important in controlling marsh dynamics and serves as a guide to potential management actions for marsh protection. [ABSTRACT FROM AUTHOR]

• A generalized Reissner theory is applied to various circular and annular plates. • Large, linearly elastic, axisymmetric deflections, rotations, and strains are allowed. • Pressure, point load, edge moment, and ponding are treated. • Effects of loading magnitude, plate geometry, and Poisson's ratio are studied. • Results are compared to those of von Kármán, Reissner, and linear theories. A generalized Reissner theory for axisymmetric problems of thin circular and annular plates is applied to various problems. The plates are assumed to be linearly elastic, and shear deformation is neglected. Large deflections, rotations, and strains are allowed. The plate edges may be clamped or simply supported, movable or immovable. The types of loading considered are uniform pressure, central concentrated load, uniform edge moment, full ponding, and central rigid hub pushed downward (with or without an elastic foundation). In some cases, the effects of Poisson's ratio and the radius-to-thickness ratio are investigated, and the maximum deflections are compared to those based on von Kármán theory and Reissner theory. [ABSTRACT FROM AUTHOR]

The partitioning of different grain‐size classes in gravity flow deposits is one of the key characteristics used to infer depositional processes. Turbidites have relatively clean sandstones with most of their clay deposited as part of a mudstone cap or as a distal mudstone layer, whereas sand‐bearing debrites commonly comprise mixtures of sand grains and interstitial clay; hybrid event beds develop alternations of clean and dirty (clay‐rich) sandstones in varying proportions. Analysis of co‐genetic mudstone caps in terms of thickness and composition is a novel approach that can provide new insight into gravity flow depositional processes. Bed thickness data from the ponded Castagnola system show that turbidites contain more clay overall than do hybrid event beds. The Castagnola system is characterized by deposits of two very different petrographic types. Thanks to this duality, analyses of sandstone and mudstone composition allow inference of which proportion of the clay in each of the deposit types was acquired en route. In combination with standard sedimentological observations the new data allow insight into the likely characteristics of their parent flows. Clean turbidites were deposited by lower concentration, long duration, erosive, muddy turbidity currents which were more efficient at fractionating clay particles away from their basal layer. Hybrid event beds were deposited by shorter duration, higher‐concentration, less‐erosive sandier flows which were less efficient at clay fractionation. The results are consistent with data from other turbidite systems (for example, Marnoso‐arenacea). The approach represents a new method to infer the controls on the degree of clay partitioning in gravity flow deposits. [ABSTRACT FROM AUTHOR]

Salt marshes are at risk globally if they cannot keep pace with sea level rise. Along the United States Mid-Atlantic coast, high marsh has already declined, and is particularly vulnerable to future loss due to greater regional rates of relative sea level rise and limited capacity for both vertical accretion and landward migration. To support climate adaptation efforts in the region, we conducted a spatial overlay analysis to (1) assess interior ponding in the high tidal marsh zone caused by waterlogging, and (2) identify restoration opportunities where poor drainage is limiting natural recovery. Surface inundation has increased across over 14,000 ha of high marsh in the region, mostly along the eastern Chesapeake Bay and New Jersey coast. Within this waterlogged area, we identified 239 potential restoration sites (275 ha). Validation data indicate our analysis had relatively high accuracy in identifying potential restoration sites, with a true positive rate of 76% and a true negative rate of 96%. Widespread waterlogging emphasizes the need for climate adaptation efforts to restore and protect high marsh in the face of future change. Our recommended restoration strategy of connecting waterlogged sites to tidal creeks aligns with best practices by enabling drainage of high marsh to halt or even reverse ponding, improve recovery from future flooding events, and ultimately facilitate marsh migration with sea level rise. [ABSTRACT FROM AUTHOR]

Abstract Traffic management and drainage system are two vital issues for any metropolitan city. Like other big cities, Karachi is also facing problems due to lack of traffic management and poor drainage system. The main objective of the study is to model the interdisciplinary issues of storm water and its effect on the traffic of Karachi. The specific objectives are: (1) to calibrate and validate urban hydraulic and traffic micro-simulation models and (2) to model storm water and traffic for future conditions. This study is carried out on a 3-km section of arterial road. In this study, loose coupling of two models is done. For urban drainage, PCSWMM, and for traffic, VISSIM is used. Both models are calibrated for an existing situation on rainfall event of August 3, 2013, and then used for prediction of future scenario based on 50-year and 100-year return periods of rainfall. Sensitivity analysis of VISSIM is performed. Locations and lengths of road sections, where ponding happens for the future scenario, are identified using PCSWMM. These lengths are then marked in VISSIM as low-speed areas, and delays are measured. Analysis of PCSWMM shows that for 100-year return period, there is maximum 0.318 ha-m (3180 cubic meters) water stored in the depressions of the road after 10 h of rainfall. Analysis of VISSIM shows that for a 100-year return period, there is a maximum delay of 35 min on NIPA to Hasan Square section of University Road.

This study assessed the conditions of wetland hydrology, hydrophyte and soil under different state and federal conservation programs, and then identified the restorable potential of conserved playas. The distribution of hydrology and hydrophyte were geospatially examined through annual tracking the quantity and quality of wetlands on historical hydric soil footprints under different conservation programs in the Rainwater Basin in Nebraska, USA during 2004–2015. The results show that the historical hydric soil footprints with the conservation programs had significantly better performance in ponded water and hydrophyte than non-conserved wetlands. The yearly average of ponded water areas within footprints varies at 12.59% for the Waterfowl Production Areas (WPAs), 14.78% for Wildlife Management Areas (WMAs), 27.37% for Wetlands Reserve Program's conservation easements (WRPs), and 1.86% for non-conserved wetlands, respectively. The yearly average of hydrophyte plant community coverage within footprints reaches at 77.51% for WPAs, 79.28% for WMAs, and 66.53% for WRPs, and 8.82% for non-conserved hydric footprints. Within conserved lands, Massie/Water soil series demonstrated the prominent ability to hold ponding water, especially in the ponded footprints with higher ponding frequency. Nevertheless, the proportion of Fillmore, Rusco or Butler soil series roughly decreased when the ponding water frequency increased. The areas, with high likelihood to be restored, are the places between annual ponding/hydrophyte covered areas and 11 years' maximized ponding/hydrophyte areas. [ABSTRACT FROM AUTHOR]

The China–Russia crude oil pipeline (CRCOP) traverses rivers, forests, and mountains over permafrost regions in northeastern China. Water accumulates beside the pipe embankment, which disturbs the hydrothermal balance of permafrost underlying the pipeline. Ground surface flows along the pipeline erode the pipe embankment, which threatens the CRCOP’s operational safety. Additionally, frost heave and thaw settlement can induce differential deformation of the pipes. Therefore, it is necessary to acquire the spatial distribution of water features along the CRCOP, and analyze the various hazard probabilities and their controlling factors. In this paper, information regarding the permafrost type, buried depth of the pipe, soil type, landforms, and vegetation were collected along the CRCOP every 2 km. Ponding and erosive damage caused by surface flows were measured via field investigations and remote sensing images. Two hundred and sixty-four pond sites were extracted from Landsat 8 images, in which the areas of 46.8% of the ponds were larger than 500 m2. Several influential factors related to freeze–thaw hazards and erosive damage were selected and put into a logistic regression model to determine their corresponding risk probabilities. The results reflected the distributions, and forecasted the occurrences, of freeze–thaw hazards and erosive damage. The sections of pipe with the highest risks of freeze–thaw and erosive damage accounted for 2.4% and 6.7%, respectively, of the pipeline. Permafrost type and the position where runoff encounters the pipeline were the dominant influences on the freeze–thaw hazards, while the runoff–pipe position, buried depth of the pipe, and landform types played a dominant role in erosive damage along the CRCOP. Combined with the geographic information system (GIS), field surveys, image interpretation and model calculations are effective methods for assessing the various hazards along the CRCOP in permafrost regions.

Abstract Tabular beds and sheet-like deposits in deep-water systems have been the subject of much research attention; they can form high quality hydrocarbon reservoirs, owing to their excellent lateral continuity and predictable geometry. Additionally, deposit tabularity is a piece of evidence used to infer flow confinement in ancient systems and thus to evaluate the suitability of outcrop datasets as reservoir analogues. However, the quantification of tabularity is rarely attempted and a consistent definition on how to describe it quantitatively is lacking. For this study, published data from eighteen well-constrained ancient turbidite systems in outcrop were analysed. A simple and novel methodology for the quantitative calculation of tabularity along a transect from log panels and photo panels was devised, based on: a) subdividing beds into two groups based on their thickness, b) calculating the percentage of beds continuous across a fixed window (500 m) and c) calculating the rate of thinning for the continuous beds within the same window. Calculations obtained from multiple locations within individual systems enable the investigation of proximal to distal, and axial to lateral changes in tabularity to be captured, and therefore permits the evaluation of tabularity in three-dimensions. A comparison between tabularity of the considered systems and their inferred degree of basin confinement shows that in the confined systems ≥90% of beds are continuous over 500 m compared to ≤40% for the two unconfined systems studied. In addition, different bed types were compared: hybrid event bed thinning rates are shown to be up to three times those of classical turbidites. This methodology provides a new tool to compare tabularity within and between systems quantitatively. It is hoped that the quantitative determination of tabularity will become a common workflow when describing ancient turbidite systems. It is suggested that this approach will enhance the value of outcrop data to inform models capturing the architecture of systems analogous to subsurface hydrocarbon reservoirs. Highlights • Novel methodology for quantifying tabularity based on bed continuity and bed thinning. • Tabularity values from published studies of eighteen ancient turbidite systems. • In the studied systems bed continuity is higher in confined systems. • Quantitative determination of tabularity should become a standard workflow in outcrop. [ABSTRACT FROM AUTHOR]

Traffic management and drainage system are two vital issues for any metropolitan city. Like other big cities, Karachi is also facing problems due to lack of traffic management and poor drainage system. The main objective of the study is to model the interdisciplinary issues of storm water and its effect on the traffic of Karachi. The specific objectives are: (1) to calibrate and validate urban hydraulic and traffic micro-simulation models and (2) to model storm water and traffic for future conditions. This study is carried out on a 3-km section of arterial road. In this study, loose coupling of two models is done. For urban drainage, PCSWMM, and for traffic, VISSIM is used. Both models are calibrated for an existing situation on rainfall event of August 3, 2013, and then used for prediction of future scenario based on 50-year and 100-year return periods of rainfall. Sensitivity analysis of VISSIM is performed. Locations and lengths of road sections, where ponding happens for the future scenario, are identified using PCSWMM. These lengths are then marked in VISSIM as low-speed areas, and delays are measured. Analysis of PCSWMM shows that for 100-year return period, there is maximum 0.318 ha-m (3180 cubic meters) water stored in the depressions of the road after 10 h of rainfall. Analysis of VISSIM shows that for a 100-year return period, there is a maximum delay of 35 min on NIPA to Hasan Square section of University Road. [ABSTRACT FROM AUTHOR]

Mass-transport deposits (MTDs) generate seafloor topography that can strongly influence the stratigraphic architecture of submarine channels. In deep-water depositional environments, both MTDs and turbidity currents are commonly fed into basins from a single point source, and turbidites may be observed ponding on top of, between, and beside MTDs. This study uses core data and 3D seismic reflection data to classify two major types of MTDs, 1) long-runout MTDs, which are radial in plan view and mounded, and 2) short-runout MTDs, which are elongate and weakly layered. Both MTD types deposited transversely into a deep-water axial channel belt in the lower Puchkirchen Formation in the Molasse Basin of Austria. Unlike longitudinally-emplaced MTDs previously identified in the upper Puchkirchen Formation, the surface topography of transversely-emplaced MTDs, especially those of the long-runout MTDs, provided accommodation for the ponding of sediments on a scale similar to that of large supra-MTD ponded turbidite intervals identified globally. Moreover, both types of transversely-emplaced MTDs enhanced syn-tectonic northward migration of the northern margin of the channel belt and delivered large quantities of fine-grained material that likely contributed to the mud-rich lithofacies that comprise a significant fraction of the lower Puchkirchen Formation. Our work suggests that supra-MTD ponded deposits could contain hydrocarbon reservoir units in regions previously regarded as waste zones. More broadly, this study characterizes how transversely-emplaced MTDs influence seafloor topography, submarine channel morphology, and the distribution of reservoir facies in a depositional system characterized by axial sediment transport. [ABSTRACT FROM AUTHOR]

[Display omitted] • An integrated framework (TV-BMA) was proposed for urban flood prediction. • Ponding prediction models for different rainfall patterns were constructed. • TV-BMA had 11.4–50.4% higher prediction accuracy than the four benchmark models. • Dynamic early warning provided using rainfall prediction data and the TV-BMA model. • The TV-BMA model achieved 80 % precision for a forecast period of 100 min. Urban flooding is a serious challenge in cities owing to global warming and rapid urbanization; thus, urban flood forecasting is required to reduce losses. Nevertheless, owing to the randomness and uncertainty of rainfall and ponding processes, providing accurate and stable ponding predictions using the existing prediction methods is difficult. To address these issues, this study proposes a time-varying criterion to improve the Bayesian model averaging (BMA) method and uses the time-varying BMA (TV-BMA) approach to develop an integrated model for predicting urban floods and providing early warning by dynamically coupling the results of the BMA and three machine-learning models. This integrated model was based on numerous measured data on rainfall and ponding processes, aiming to accurately predict real-time changes in ponding depth. The results show that the prediction accuracy of the TV-BMA model was 11.4–50.4 % higher than that of the BMA and individual models, and within the 95 % confidence interval. Moreover, the bandwidth of the TV-BMA model (0.038 m) was 19.1–53.1 % lower than that of the BMA (0.047 m) and individual models (0.063–0.081 m). This demonstrates that the TV-BMA model has significant advantages in correcting deviation and reducing uncertainty in the prediction results. Furthermore, the TV-BMA model has high accuracy in the early warning results for up to a 100-min forecast period (F-score > 0.8). The proposed TV-BMA model can predict urban floods with improved accuracy and stability. It may provide guidance for improving the existing urban flood prediction methods. [ABSTRACT FROM AUTHOR]

Due to recent improvements in commercially available programming and modelling tools, the role of the tension structures engineer is increasingly being expanded beyond the traditional disciplines of form finding, static load analysis and creation of fabrication geometry. The engineer is now able to consider a variety of peripheral analytical considerations, including transient or time stepping studies. These developments may require the enhancement of in-house software tools or combining current software capabilities with third party tools. This concept is illustrated with reference to three examples applied to recent structures; the creation of a hydraulic flow tool allowing the assessment of water flow over a complex 3d surface, automated time stepping of existing static analysis tools to provide an assessment of structural response under a transient hydrostatic load and finally a batch processed sequence of static analyses to determine the risk and potential mechanisms for a progressive collapse. [ABSTRACT FROM AUTHOR]