Sediment Model Research Articles

Machine learning-based modeling of surface sediment concentration in Doce river basin

As sediment measurements are laborious and costly, alternative techniques are required to provide such information from more easily measured variables. Thus, the objective of this study was to use machine learning-based models to predict the surface sediment concentration (SSC) in the Doce river basin. The cross-sectional averages of measurements from seven sediment monitoring stations of the Agência Nacional de Águas e Saneamento Básico located in the Doce riverbed were used as the SSC data. A total of 62 predictor variables were used, which were derived from data on the terrain slope, pedology, land use and cover, precipitation, river discharge and velocity, actual evapotranspiration, surface runoff, soil moisture, temperature, and normalized difference vegetation index. The Boruta and recursive feature elimination variable selection methods were employed to reduce the number of predictor variables. The random forest, Cubist, support vector machine, and eXtreme Gradient Boosting (XGBoost) algorithms as well as least absolute shrinkage and selection operator (LASSO) regression were applied to predict the SSC data. The machine learning algorithms provided superior results, particularly the Cubist and XGBoost models, which exhibited the lowest prediction error and highest efficiency metrics. According to the varImp function from Caret package, the most important predictor variables for the SSC modeling were the daily river discharge on the sediment collection date and time-lagged discharge. The cumulative daily mean precipitation was also important for the sediment modeling. Our findings demonstrate that machine learning models may be a very helpful tool for sediment monitoring and understanding sediment dynamics in the Doce river basin over time.

Steady rheological behavior and unified strength model for reconstituted deep-sea sediments

Investigation of the rheological characteristics of deep-sea sediments is very important for understanding submarine disasters. Three reconstituted deep-sea soils with different plasticity and activity values from the South Sea China are considered in this study. A series of steady rheological tests are conducted on samples of three soils with different water contents and temperatures by a rate-controlled rotational rheometer operated in a steady-state regime. Rheological results show that shear stress and apparent viscosity can be decreased by a maximum of 65% when the temperature varies from 1 °C to 25 °C, and the three deep-sea soils are typical shear thinning non-Newtonian fluids with yield stress. The state of the samples can be divided into three phases during the shearing process, which implies that with an increase in the shear strain rate, all samples first behave as a solid, then transition from solid to liquid, and last behave as a liquid. The three phases are distinguished by the static yield stress (SYS) and fluidic yield stress (FYS), and a simple method for dividing the three phases is proposed. The SYS and FYS decreased with increasing temperature and water content. The relationships between yield stresses (SYS and FYS) and soil properties (water content and activity) and temperature are established. In addition, a unified strength model for deep-sea sediments is suggested, and the validity of the model is verified by comparing the prediction results of the model and test results. The results of this study could be useful for deep-sea submarine mudflow and landslide modelling.

Multiple elastic attribute fusion approach based on affinity propagation clustering strategy for gas hydrate reservoir identification

Pre-stack seismic inversion based on sensitive elastic parameters is critical in reservoir lithology prediction and geofluid identification. The ability of a single elastic attribute to identify a reservoir depends on its sufficient sensitivity to distinguish the target reservoir from the surrounding sediments. In general, high-dimensional data space composed of multiple elastic attributes is more conducive to describing reservoir characteristics. Therefore, a multiple elastic attribute fusion method using affinity propagation clustering strategy for gas hydrate reservoir identification is proposed. Rock-physics modeling is the most effective tool to determine the influence of microscopic physical parameters on macroscopic elastic response and to quantitatively evaluate the sensitivity of elastic attributes. Consequently, a rock-physics model of hydrate sediments considering the non-negligible shear properties of hydrates is constructed to clarify reservoir-sensitive elastic parameters. Additionally, a clustering evaluation indicator is defined to determine the optimal data clustering dimension in terms of feasibility and economy of the proposed method, and to avoid bias in the results due to data redundancy. It is shown that the 3D elastic attribute space consisting of shear modulus, Young's modulus, and S-wave velocity has the best discrimination ability for hydrate reservoirs. The logging data are used to verify the feasibility and effectiveness of the proposed method. Finally, the hydrate reservoir development is accurately discriminated by using the multiple elastic attributes yield from the pre-stack seismic inversion and combined with the fusion strategy.

Progressive bridge collapse analysis under both scour and floods by coupling simulation in structural and hydraulic fields. Part Ⅰ: Numerical solver

Hydraulic bridge failures have become the greatest threat to the structural safety of bridges. Combined numerical simulations are rare due to the high computational cost of structural nonlinear finite element analysis (NLFEA) and computing fluid dynamics (CFD). Structural analysis and design for extreme hydrological hazards are challenging due to complicated hydrodynamics-soil-structure interactions. This paper proposes a numerical solver to simulate hydraulic bridge failures through coupling simulations. The solver applies hydrodynamic load and updates scour boundary in a structural model by utilizing a scatter linear interpolation method based on the Delaunay triangulation algorithm in each loop solution. Then, a simplified sediment stress model considering external forces in the vertical plane and a complex model with an arbitrary slope in three-dimensional coordinates are introduced into the basic incipient motion model of sediment, resulting in a more realistic stress state of sediment. Finally, the numerical solver is adapted to provide an accessible method to investigate the influence of such a modified model on the scour process and structure response. Meanwhile, the validation of this numerical solver is conducted in a companion paper based on the comparison between the numerical result of the hybrid model and the field data.

Characterizing Trace Metal Contamination and Partitioning in the Rivers and Sediments of Western Europe Watersheds

Adsorption and desorption processes occurring on suspended and bed sediments were studied in two datasets from western Europe watersheds (Meuse and Mosel). Copper and zinc dissolved and total concentrations, total suspended sediment concentrations, mass concentrations, and grain sizes were analyzed. Four classes of mineral particle size were determined. Grain size distribution had to be considered in order to assess the trace metal particulate phase in the water column. The partitioning coefficients of trace metals between the dissolved and particulate phases were calculated. The objective of this study was to improve the description of the processes involved in the transportation and fate of trace metals in river aquatic ecosystems. Useful data for future modelling, management and contamination assessment of river sediments were provided. As it is confirmed by a literature review, the copper and zinc partitioning coefficients calculated in this study are reliable. The knowledge related to copper and zinc (e.g., partitioning coefficients) will allow us to begin investigations into environmental modelling. This modelling will allow us to consider new sorption processes and better describe trace metal and sediment fates as well as pressure–impact relationships.

The importance of acid-processed meteoric smoke relative to meteoric fragments for crystal nucleation in polar stratospheric clouds

Abstract. The crystal formation of nitric acid trihydrate (NAT) in the absence of water ice is important for a subset of polar stratospheric clouds (PSCs) and thereby ozone depletion. It has been suggested that either fragmented meteoroids or meteoric smoke particles (MSPs), or possibly both, are important as heterogeneous nuclei of these crystals. Previous work has focused on the nucleating ability of meteoric material in nitric acid in the absence of sulfuric acid. However, it is known that when immersed in stratospheric sulfuric acid droplets, metal-containing meteoric material particles partially dissolve and components can reprecipitate as silica and alumina that have different morphologies to the original meteoric material. Hence, in this study, we experimentally and theoretically explore the relative role that sulfuric acid-processed MSPs and meteoric fragments may play in NAT nucleation in PSCs. We compared meteoric fragments that had recently been prepared (by milling a meteorite sample) to a sample annealed under conditions designed to simulate heating during entry into the Earth's atmosphere. Whilst the addition of sulfuric acid decreased the nucleating ability of the recently milled meteoric material relative to nucleation in binary nitric acid-water solutions (at similar NAT saturation ratio), the annealed meteoric fragments nucleated NAT with a similar effectiveness in both solutions. However, combining our results with measured fluxes of meteoric material to the Earth, sedimentation modelling and recent experiments on fragmentation of incoming meteoroids suggests that it is unlikely for there to be sufficient fragments to contribute to the nucleation of crystalline NAT particles. We then considered silica formed from sulfuric acid-processed MSPs. Our previous work showed that nanoparticulate silica (radius ∼6 nm) is a relatively poor promoter of nucleation compared with micron-scaled silica particles, which were more effective. Both materials have similar chemical and structural (crystallographically amorphous) properties, indicating that size is critical. Here, we account for surface curvature of primary grains using the Classical Nucleation Theory (CNT) to explore this size dependence. This model is able to explain the discrepancy in nucleation effectiveness of fumed silica and fused quartz by treating their nucleating activity (contact angle) as equal but with differing particle size (or surface curvature), assuming interfacial energies that are physically reasonable. Here, we use this CNT model to present evidence that nucleation of NAT on acid-processed MSPs, where the primary grain size is tens of nanometres, is also effective enough to contribute to NAT crystals in early season PSCs where there is an absence of ice. This study demonstrates that the modelling of crystal nucleation in PSCs and resulting ozone depletion relies on an accurate understanding of the transport and chemical processing of MSPs. This will affect estimated sensitivity of stratospheric chemistry to rare events such as large volcanic eruptions and long-term forecasting of ozone recovery in a changing climate.

Simulating daily sediment transport using the Water Quality and Sediment Model (WQSED)

IntroductionHigh erosion and sediment yield rates continue to pose a significant threat to the environment globally. Information on erosion and sediment rates is key for supporting effective and sustainable mitigation measures. Models that estimate sediment yield are vital in providing information about erosion and sediment yield rates, as empirical studies are prohibitive over large spatial and temporal scales.MethodsIn this study, we simulate daily sediment transport using the WQSED model and assess the effectiveness of the tool in providing crucial estimations of sediment yield. The model structure links the Modified Universal Soil Loss Equation (MUSLE) to a simple sediment storage component. The model was applied to the Odzi River catchment in Zimbabwe and The Rio Tanama River catchment in Puerto Rico, where daily observations of sediment yield exceeding a decade were available for calibration and validation.ResultsIn both catchments, we achieved a coefficient of efficiency and R2 and NSE of > 0.7 during model calibration and > 0.6 during model validation. The percentage bias remained below 45% for both calibration and validation periods.ConclusionThese results indicate that the WQSED model can be applied to provide estimates of sediment yield that are reliable for erosion, sediment yield and water quality management. An effective and relatively simple sediment yield model incorporating sediment storage is essential for catchment management in erosion-prone areas.

Diffusive gradients in thin films for transfer of phosphorus, nitrate and ammonium in lake sediments

There is a lack of the understanding of the transfer of phosphate (PO4-P), ammonium (NH4-N) and nitrate (NO3-N) at the millimeter scale in sediments related to internal loadings in the semi-arid and cold Lake Hulun in China. In this paper, a passive sampling technique-diffusion gradients in thin films (DGT) has been used for the biogeochemical behaviors and dynamic transfer of PO4-P, NH4-N and NO3-N in sediments in this lake. The two-sided DGT probe (AMP-TH&ZrO-Chelex) and ZrO DGT piston are designed for sediment/water interface. Based on change characters of DGT concentration profiles (nutrients, Fe and Mn) related to redox status and chemical properties, N and P mobilizations are derived. The reductive dissolution of Mn(IV) or Fe(III) (oxyhydr)oxides accounts for subsequent P release is corresponded with the oxic or anoxic status in sediment layers; Fe(III)-reduction is the main reason for P remobilization. The breakdown of algae biomass deposited on the uppermost sediment and phosphatase enzymes activity enhanced by NH4-N also lead to P remobilization. In sub-anoxic or anoxic layer, denitrification and dissimilatory nitrate reduction to ammonium (DNRA) induce exchangeable ammonium (NH4ex) enrichment and NH4-N release, while, anammox depletes NH4-N mobility. Aerobic nitrification results in NO3-N remobilization. Organic matter favors NH4-N release. DGT induced fluxes in sediments (DIFS) model is used to derive the labile P pool (51.5–465.5 cm3 g−1), resupply constant (0.186–0.734), response time (54–11,070 s) and Dspt rate (32–382,517 nmol cm−3 d−1) for describing dynamic P transfers with two opposite types of “slow” and “fast” resupplies. The diffusive fluxes across sediment/water interface in ranges of 67.9–498.7 μg m−2 d−1 (PO4-P), −1416–106.8 (NH4-N) and –2147–301.1 μg m−2 d−1 (NO3-N) and DIFS parameters can be used for release risks in lake regions and the sediment remediation strategies are recommended.

Response of Soil Detachment Rate to Sediment Load and Model Examination: A Key Process Simulation of Rill Erosion on Steep Loessial Hillslopes.

The rate of soil detachment by water flow indicates soil erosion intensity directly. The exact relation between soil detachment rate and actual sediment load in water flow, however, is still unclear, and the existing relationships have not been adequately tested. The aims of the present study were to investigate the response of soil detachment rate to sediment load using rill flume data with loessial soil and to quantitatively examine the soil detachment equations in the WEPP and EUROSEM soil erosion models. Six slopes were combined with seven flow discharges to measure detachment rates under seven sediment loads using a rill flume with a soil-feeding hopper. Significant differences were found among the soil detachment rate by different sediment loads in low sediment load levels, but an insensitive response of soil detachment rate to sediment load was found under high levels of sediment load. The soil detachment rate was proved to be negatively linearly correlated with sediment load. The rill detachment equation in the WEPP model predicted the soil detachment rate by rill flow very well under our experiment condition. The soil detachment equation in the EUROSEM model underestimated the detachment rates under controlled conditions, but removing the setting velocity from the equation greatly improved prediction. Further experiments that could reflect the dynamic convective detachment and deposition process need to be conducted to compare with the present examination results and to further understand rill erosion processes.

Analysis and Prediction of Poyang Lake’s Navigable Conditions under a New Hydrological Regime

Human activities have profoundly changed the hydrological regime and trends of rivers and lakes, which, in turn, has affected the utilization of their navigable conditions. However, few studies have focused on the effects of changes in hydrological regimes and trends of rivers and lakes on navigable conditions. Thus, this study intensively analyzes and investigates the navigable depth at the major control sections in the lake area during the dry season in the period before 2002, when the Three Gorges Reservoir was not yet constructed, and the period from 2003 to 2019, when the Three Gorges Project was put into operation with impoundment based on the dry-season water level curve in the Poyang Lake area since the operation of the Three Gorges Reservoir. This study also further analyzes the influence of the change in the hydrological regime on the navigable depth in the lake area. The results show that the waterway depth and width could meet the navigation requirements before 2002. From 2003 to 2019, whereas the water level with a 98% guarantee rate of duration at the Xingzi Hydrometric Station decreased, that at the Hukou Hydrometric Station increased. The waterway depth and width at both the Hukou and Xingzi hydrometric stations could meet the requirements of the size of Grade II waterways. This study also performs a simulation prediction of the water regime of Poyang Lake under a new hydrological regime using the mathematical model of water and sediment of the Changjiang River Scientific Research Institute. The results reveal that in 2030 and 2050, after the Three Gorges Reservoir has been in operation for 30–50 years, the water levels at the Hukou, Xingzi, and Wucheng hydrometric stations (Hukou) of Poyang Lake will decline by approximately 0.18–0.66 and 0.10–0.24 m, respectively. Although the overall navigable depth can basically meet the navigation requirements for a period of time, the trend of the long-term declining water level may cause unsafe navigation risks.

Semi-theoretical model for mean sediment resting time of spherical particles: the role of hydrodynamic impulses and sphere size nonuniformity

Semi-theoretical model for mean sediment resting time of spherical particles: the role of hydrodynamic impulses and sphere size nonuniformity

The Failure Mechanism of Methane Hydrate-Bearing Specimen Based on Energy Analysis Using Discrete Element Method

Studying the failure mechanism of methane hydrate specimens (MHSs) is of great significance to the exploitation of methane hydrate. Most previous studies have focused on the macro or micromechanical response of MHS under different conditions. However, there are a few studies that have investigated the mechanical response mechanism of MHS based on energy evolution. Therefore, in this study, a numerical model of the methane hydrate-bearing sediments was constructed in the particle flow code (PFC) environment. Then, the numerical model was validated using the conducted laboratory tests; and a series of numerical tests were conducted under different methane hydrate saturation conditions, and the obtained results were analyzed. These results qualitatively describe the main mechanical properties of the methane hydrate-bearing sediments from the viewpoint of energy evolution. The simulation results indicated that during the shear test, the bond breaks at first. Then, the soil particles (sediments) start to roll and rarely slid before shear strength arrives at the highest value. Around the highest shear strength value, more soil particles begin to roll until they occlude with each other. Strain softening is induced by the combined action of the breakage of the hydrate bond and the slipping of soil particles. The higher the hydrate saturation is, the more obvious the strain softening is. Considering that a good agreement was observed between the numerical simulation results and the laboratory test results, it can be concluded that the numerical simulation approach can complement the existing experimental techniques, and also can further clarify the deformation and failure mechanism of various methane hydrate-bearing sediments. The results obtained from the present study will contribute to a better understanding of the mechanical behavior of the gas hydrate-bearing sediments during hydrate dissociation and gas exploitation.

Wind effect on sediment suspensions over silt-dominated mixtures: An experimental study

A series of laboratory experiments have been conducted to explore the wind effect on Sediment Suspended Concentrations (SSCs) in fine-grained coastal systems. The paddle waves were overplayed with surface-blowing winds in a wind-wave flume to mimic offshore swells coupling with local wind waves during rough weather. Both SSCs and water turbulences under different wind and wave conditions have been investigated over two kinds of sediment beds (Sediment 1, S1, D50 = 52µm and Sediment 2, S2, D50 = 90µm). The High Concentration Layers (HCL) were formed under most of the wave-only conditions, while with the introduction of the stronger wind, more sediment suspensions were transported upward, increasing SSCs in upper water elevations. The finer sediment S1 is easier to suspend than S2 under the same conditions. The enhancement of the vertical turbulence intensity (σw) by winds is the main reason for the increase in SSCs. Meanwhile, because the wind-induced turbulence can hardly penetrate the HCL, the turbulence intensities outside the HCL can be further amplified compared to the experiment without a sediment bed. The wind contributes over 65% of the SSC enlargement above the HCL under a wind of 10m/s for S1, while less than 20% inside the HCL in most wind conditions. The sediment mixing coefficient (ϵs), a crucial parameter for suspended sediment modeling, was enhanced with stronger winds. Although the existing formulas for the vertical distribution of ϵs are valid under both wave-only and small winds (2.5 m/s) for both sediment beds, the enhancement of ϵs caused by strong winds cannot be captured, requiring further research.

Strength Behaviors and Constitutive Model of Gas-Saturated Methane Hydrate-Bearing Sediment in Gas-Rich Phase Environment

Natural gas hydrates occupy an important position in the development of clean energy around the world in the 21st century. It is of great significance to research the mechanical properties of methane hydrate-bearing sediment (MHBS). In this paper, gas-saturated MHBS were synthesized based on the self-developed triaxial compressor apparatus. The triaxial shear tests were performed at temperatures of 2 °C, 3 °C, and 5 °C and confining pressures of 7.5 MPa, 10 MPa, and 15 MPa. Results indicate that the axial strain process can be divided into three stages: initial elastic deformation, initial yield deformation, and strain softening. When confining pressure is increased, the shear strength of MHBS increases at a lower confining pressure. In contrast, shear strength appears to decrease with increasing confining pressure at a higher confining pressure. There is a negative correlation between temperature and shear strength of MHBS. The initial yield strain of MHBS increases in condition due to the increase in confining pressure and the decrease in temperature. The change in strength degradation is kept within 2 MPa. Using test data, the Duncan-Chang model was modified to describe the strength behaviors of gas-saturated MHBS. The accuracy of the model was verified by comparing calculated values with test data.

Substantial increase in P release following conversion of coastal wetlands to aquaculture ponds from altered kinetic exchange and resupply capacity

The reclamation of wetlands and its subsequent conversion to aquaculture may alter regional nutrient (im)mobilization and cycling, although direct assessments of phosphorus (P) cycling and its budget balance following wetland conversion are currently scarce. Here, parallel field experiments were conducted to investigate and compare the availability and mobilization mechanisms of P from natural coastal wetlands and the adjacent converted aquaculture ponds based on high-resolution diffusive gradient in thin films (DGT) and dialysis (HR-Peeper) techniques and the DGT-induced fluxes in sediments (DIFS) model. The study found that the conversion of wetland to pond strongly reduced the sediment P pool by changing its forms and distribution. High-resolution data showed that concentrations of labile P and soluble reactive P across the sediment–water profiles were markedly enhanced by the converted aquaculture pond, although they exhibited large spatiotemporal heterogeneity. Moreover, the synchronous distribution of labile P, iron (Fe) and sulfur (S) across profiles in coastal wetlands indicated that the dissolution of Fe (III) oxyhydroxide–phosphate complexes coupled with sulfate reduction were the main mechanisms regulating sediment P mobilization in coastal areas. However, the converted aquaculture pond weakened or even reversed this dependence by decoupling the Fe-S-P reactions by changing the sediment structure and nutrient balance. Substantial increases in labile P, Fe and S fluxes in the pond suggested the conversion of wetland to aquaculture facilitated the internal release of P, Fe and S from sediment into water. The high resupply parameter (R) and desorption rate (k-1) combined with low response time (Tc) in the pond, as fitted by DIFS model, indicated the strong resupply capacity and fast kinetic exchange of sediment P across the sediment–water interface, which is consistent with the high P diffusion fluxes recorded in the pond. It was concluded that converted aquaculture ponds act as an important source of P release in coastal areas, potentially exacerbating water quality degradation and eutrophication. Specific initiatives and actions are therefore urgently needed to alleviate the internal P-loading during aquaculture.

Combining passive sampling with fraction transfer and toxicokinetic modeling to assess bioavailability of organic pollutants in a benthic invertebrate, Lumbriculus variegatus

This study investigated passive adsorption of nine antipsychotic drugs by the benthic oligochaete, Lumbriculus variegatus from spiked freshwater sediments. Based on a combination of diffusive gradients in thin-films (DGT) passive sampling and modelling, specifically the DGT-induced fluxes in sediments (DIFS) model and fractions-transfer models, an uptake and diffusion-induced model was established for oligochaetes. Lamotrigine and bupropion showed positive fluxes from sediment to overlying water. Oligochaetes accumulated both lamotrigine and carbamazepine. The simulation model for transfer showed that after 30 days antipsychotic compounds in sediment were present predominantly in stable or bound fractions, rather than labile fractions. Dissolved organic carbon and degradation were important drivers of dissipation rates of antipsychotic compounds in sediments and labile pool size. Uptake by oligochaetes and diffusion-induced models matched measured concentrations well ( R 2 = 0.83–0.95 and R 2 = 0.99–1.00, respectively). Processes of uptake by oligochaetes were comparable to DIFS results, where fast desorption to the labile pool in the short response time and adsorption processes, except carbamazepine and lamotrigine, in sediments dominated kinetics. It suggests a link between bioavailability of organic pollutants for sediment-dwelling organisms and desorption kinetics involved with fractions transfer within sediments, which has important implications for the environmental risk assessment of these chemicals. • Organic pollutants could be passively adsorbed by benthic worms. • Sediment porewater and DOC are the major sources for passive adsorption by benthic worms. • The contribution of worm passive uptake is < 1% from the dissipation in sediments.

Hydrodynamics and Sediment Modelling for a Fishery Harbour at Konkan Region of Maharashtra, India

Hydrodynamics and Sediment Modelling for a Fishery Harbour at Konkan Region of Maharashtra, India

The constitutive behavior and dissociation effect of hydrate-bearing sediment within a granular thermodynamic framework

Considering the energy dissipation caused by hydrate dissociation and granular rearrangement at the micro level, a multiphase constitutive model of hydrate-bearing sediment is established within a granular thermodynamic framework. This model incorporates the nonlinear expression of bonding stress into the elastic energy density function, considers the relative velocities of the gas and liquid phases in terms of the solid phase in the dissipative force system, and introduces the coupling effect of heat conduction into the migration coefficient matrix to capture the complex behavior of the sediment. Defining the migration coefficient matrix and elastic energy function, the effective stress is obtained and is suitable for constant hydrate saturation and hydrate dissociation conditions. Dilatancy equations are improved by considering the effect of compactness, bonding stress, and hydrate saturation. Meanwhile, the calculation method of bonding stress is suitable for both strong and weak cementation conditions. The deduced model is validated against the test results conducted on natural and synthetic samples under different hydrate saturations, sediment porosities, and hydrate habits and can effectively capture the strain hardening and softening as well as the dilatancy properties of the sediments and the loading path effect.

Numerical Modelling of Shoreline changes of Galesong, Takalar’s coast

Morphological changes of Talakar’s coastline covering three administrative subdistrict has been modelled numerically in terms of sedimentation build up. Shoreline changes is one of the dynamic processes as parts of natural processes for coastline to reach their subsequent equilibrium resulting in bathimetrical alteration of coastal bed. Sedimentation modeling simulation has been conducted for the coastlines of North Galesong, Galesong, and South Galesong subdistricts. As the location is physically affected by the oceanoghrapic dynamics of Makassar Strait, Flores Sea as well as the river hydraulics of Jeneberang and Pappa rivers’ estuaries. Shoreline accretion and abbrasion are distincted by data analysis. Sedimentation model shows shallowing process (pendangkalan) of 0.0136m to 0.05977m with 0.000006 m/day to 0.013 m/day growth near shorelines of North Galesong, 0.025202m to 0.1194 deepening and 0.02526m to 0.16736m shallowing with 0,0013 m/day to 0,013 m/day growth near shorelines of Galesong, and 0.014148 m to 0.11948 deepening and 0.01351 m - 0.16736 shallowing with 0.01m/day to 0.026 m/day growth near shorelines of South Galesong.

Comparative analysis of catagenetic maturity models for Maykop sediments in Azerbaijan

Comparative analysis of catagenetic maturity models for Maykop sediments in Azerbaijan