Mud Mass Research Articles

Investigating sediment dynamics on a continental shelf mud patch under the influence of a macrotidal estuary: A numerical modeling analysis

Shelf mud patches represent major sinks for fine-grained particles on continental shelves, as well as for carbon and contaminants of continental origin. The West Gironde Mud Patch (WGMP) is an interesting example of such offshore marine systems as it is an active mud deposition area located offshore the Gironde estuarine mouth (France) at depths between 30 and 70 m. It is known to be the trap of fine particles coming from the estuary, but the contribution of this material to the total mass of the depocenter is poorly quantified. In addition, despite the economic and ecological issues at stake, the response of such subtidal sedimentary structure to the combination of tidal currents, waves, and river supply remain poorly understood. Thus, using a realistic 3-D hydrodynamic and mixed (mud/sand) sediment transport model, this study aims at investigating the sediment dynamics of the WGMP under different hydrometeorological conditions. The analysis of the residual fluxes at the estuarine mouth exhibited large discrepancies between the different sediment classes as well as for contrasted hydro-and meteorological conditions induced by different dominant transport mechanisms. During winter, the reinforced density gradients drive strong up-estuary baroclinic circulation at the bottom that dominates the sediment dynamics over the barotropic export of mud particles. The model also reproduced the signature of a subtidal mud accumulation area over the continental shelf around 30–40 m water depth, on the proximal side of the observed WGMP. On average over two years, 26% of the mud mass accumulating on the simulated subtidal mudflat comes from the estuary. The trapping efficiency of this mud patch is negatively correlated with the significant wave height. Moreover, due to the estuarine turbid plume being more concentrated and developed at the surface during high river discharge, the trapping efficiency of the mud body is enhanced compared to lower discharge. This study highlights the sensitivity of mud and sand fluxes to vertical and horizontal residual circulation, and points out the uncertainties associated with the simulation of short-term (i.e., years) fine particle deposits compared to long-term (i.e., centuries) sediment accumulation trends. In addition, these results show the primordial effects of both wave action and riverine sediment supply on the dynamics of such subtidal muddy structures, which raises concern about their fate facing climate change and human activities in the future.

Исследование характера изменения твердости композиционных материалов с алюминиевой матрицей, упрочненной золой кокосовой скорлупы и красным шламом, с использованием анализа Тагучи

Introduction: in present scenario, light and high strength aluminium metal matrix composite are extensively used due to its high mechanical and tribological properties. Aluminium metal matrix composite reinforced with ceramic and industrial waste can customize its mechanical-chemical behavior. The purpose of the work: to create an aluminum matrix composite material using ceramic (primary) and industrial (secondary) waste represented by red mud and coconut shell ash, respectively. The mass fraction of the strengthening phase varied from 5 to 12.5 wt. % respectively with the residual mass percentage of the aluminum alloy. Method of investigation: nine specimens of composite materials were prepared by stir casting. Stirring was carried out at a speed of 50 to 100 rpm for 20 minutes at a temperature of 800 °C. Result and Discussion: the hardness behavior of the aluminum metal matrix composite was studied at an indentation load of 10, 15 and 20 kN. Taguchi method with L27 orthogonal array was selected to conduct analysis of variance (ANOVA) and regression analysis by selecting the mass percentage of red mud and mass percentage of coconut shell ash. The indentation load was used as an input parameter, and the hardness behavior was taken as an output parameter. The signal-to-noise ratio, response rank table, contour plot, and normal probability plot are investigated and it is found that hardness values improve with the addition of both reinforcing components and indenter load. The results show that the hardness value varies from 33.34 HB to 53.44 HB, and the effect of red mud mass percentage is more significant than the indenter load and coconut shell ash mass percentage.

The role of mobile muds in basin form and fill in the tectonic and sedimentologically complex region of the southeastern margin of the Caribbean Plate, Trinidad and Tobago, West Indies

The southern portions of the Barbados Accretionary Prism and the eastern deepwater region of Trinidad and Tobago is a seafloor terrane marked by scattered mud volcanoes, mud walls, and mud canopies that rise several hundred meters above the modern seafloor. We use 3D seismic and recently drilled wells to examine this area dividing it into three tectonomorphic provinces based on the nature of the mud architecture, the structuration, basin types developed and sedimentary systems occupying the basins. Mud architectures become more massive as one moves northward toward the active tectonic prism. The mud wall in the far northern Province 1 is classified as a mud canopy system; similar to those documented by Morley et al. (2022) in the North Sabah Pagasa Wedge, Borneo. The Trinidad mud canopy exhibits sutures in the mud mass margins (akin to salt “sutures”) that separate sub-masses likely composed of different materials and exhibiting different pressures and properties. These sub-masses and associated sutures are imageable using the sweetness attributes on the near stack seismic volume. Anticlines in Provinces 2 and 3, like those that are the dominant hydrocarbon-producing structures onshore and offshore Trinidad, show mobile mud cores and are associated with extensional and compressional faulting that provide pathways for hydrocarbon migration into the surrounding lutokinetic stratigraphy. A bottom simulating reflector associated with the base of the gas hydrate zone; extensive across the study area, may be a good indicator of fluid flux activity and subsurface pressure states in mud masses. It is important to employ all the seismic data volumes; full, near, mid, and far seismic data stacks, to assess different aspects of these mud diapiric systems.

Leaching phosphorous from the lime mud of kraft pulp mills: Towards sustainability

AbstractThe optimum conditions needed to separate phosphorus from the lime mud generated in kraft pulp mills were identified using different leaching solutions including carbonate, bicarbonate, and green liquor under variety of conditions. Carbonate ions seemed to be the active ion in the phosphorus leaching process. Bicarbonate solution seems to be the most effective leaching agent by removing 84% of phosphorus under the optimum operating conditions of 95°C, 2.92 m, and solution‐to‐ mud mass ratio of 3.6. The shrinking core model was used to determine the leaching mechanism and it showed that the leaching process is controlled by a mix of chemical reaction and diffusion through the particle. Two empirical models were developed to predict the leaching efficiency as a function of carbonate concentration and temperature. Counter‐current leaching was shown to be beneficial in increasing the leaching efficiency with the carbonate solutions.

Recovery of Silica from Sidoarjo Mud by Alkali Fusion

Sidoarjo mud contains potentially valuable minerals, the largest content of which is silica. Silica decomposition from Sidoarjo mud can be done by using alkaline fusion method. The purpose of this study is the recovery of silica from the Sidoarjo mud against variations in Na2CO3 alkaline fusion time. Stages Sidoarjo mud mass ratio Na2CO3 1:3 is inserted into the furnace at a temperature of 700°C with a long alkaline fusion time of 1:1.5;2;2.5; and 3 hours. Based on the calculation results, the best % recovery occurred for 3 hours, which was 48.3%. It can be concluded that the alkaline fusion time can affect the silica decomposition of the Sidoarjo mud

Diatom Assemblages from the Daginsky Mud Volcano Sediments (Eastern Sakhalin) and Their Implication

Diatom assemblages in mud volcanoes are quite rare and are poorly studied. The finding of a rich diatom flora in the sediments of the Daginsky Mud Volcano (DMV), located in the tidal zone of the Nyisky Bay of the Sea of Okhotsk, is of interest to study the conditions for the formation of host sediments in the zone of influence of various extreme factors, such as outflows of gases and water–mud mass, thermal springs, and tides. For this purpose, the taxonomical composition of diatom assemblages and concentration of diatoms in DMV sediments were studied. A comparison was made with the diatoms of geothermal springs of the Russian Far East associated with volcanic activity, and the stratigraphic occurrence of the found extinct diatoms was analyzed, which is important for determining their source and the age of the mud volcano roots. Diatom assemblages from DMV sediments are mainly characterized by the predominance of Metascolioneis tumida, Paralia sulcata, Odontella aurita, Pinnunavis yarrensis, Petroneis marina, Cocconeis scutellum, and Navicula digitoradiata. They consist of diatoms of different biotopes and extinct species. The diversity and abundance of brackish water and marine species indicates the predominant influence of sea waters on the formation of DMV sediments. The diverse freshwater species were mainly introduced into sediments with river runoff, but it is likely that some of these, such as the cosmopolitan alkaliphilic species, are inhabitants of geothermal springs. The presence of extinct species from the underlying Neogene sediments from where they were carried with gas–water–mud masses is the most typical for diatom assemblages of the DMV.

Combustion Metamorphism in Mud Volcanic Events: A Case Study of the 6 May 2000 Fire Eruption of Karabetova Gora Mud Volcano

The violent eruption of Karabetova Gora mud volcano on 6 May 2000 (Taman Peninsula, 45°12′16″ N; 36°47′05″ E) triggered gas ignition as a giant straight-flow vertical gas flare. The 400 m high, short-lived (~15 min) gas flare left no thermal halo on the ground surface, but the thermal shock caused melting or annealing of mud masses which became dispersed in ≤2 m3 blocks to distances within 30 m around the volcano conduit. The flare reached the maximum temperatures (~1400–1540 °C) at heights from 75 to 250 m, as estimated by a numerical simulation in SigmaFlow. Bulk melting of dehydrated mud masses was mostly limited to <1.5 cm near the surface of the blocks. Porous paralavas at the site consisted of low- and high-silica K-Al glasses (70%–80%) with residual unmolten grains of detrital quartz and fine (<30 µm) new phases: main intermediate members of the magnetite–ulvöspinel solid solutions and plagioclase (An45-61Ab37-44Or2-11 to An73-90Ab10-27Or0.5-1), minor cordierite (XFe = 26%–46%), pigeonite (XFe = 42%–60%), tridymite, cristobalite, and rare mullite. The metapelitic rocks affected by combustion metamorphism were heterogeneous in terms of phase composition and texture. They failed to attain homogeneity due to the high viscosity of anhydrous silicate melts and brevity of the thermal impact. The revealed features of rocks altered by a giant gas fire may serve as a proxy for phase transformation patterns in highly disequilibrium conditions of a thermal shock, far from the formation conditions of ordinary metamorphic rocks.

Synthesis of low‐costing 4A‐zeolite and stabilization of heavy metals from municipal solid waste incineration fly ash and activated red mud

AbstractTo handle the increasing environmental issues caused by red mud and municipal solid waste incineration (MSWI) fly ash, an integrated technology for its comprehensive utilization was developed through the activation of red mud followed by synthesis of 4A‐zeolite. Three influencing factors on the thermal‐alkali activation effect of red mud were investigated. Afterwards, activated red mud was combined with fly ash to synthesize 4A‐zeolite and solidify heavy metal simultaneously. The results indicated that the maximum extraction ratios of Si (57.77%) and Al (76.34%) from red mud were achieved at the NaOH/red mud mass ratio of 1.8, alkali fusion temperature of 800°C, and alkali fusion time of 120 min. Furthermore, the mixture of activated red mud and MSWI fly ash could be served as low‐costing raw materials to synthesize zeolite products with a compact structure. The solidification effect of typical heavy metals could meet GB 16889–2008 and HJ/300–2007 completely. Especially, the solidification efficiency for Cu, Zn, Pb, and Cd could reach 98.23%, 99.09%, 99.72%, and 98.21%, respectively. This paper not only solved the red mud accumulation and heavy metal pollution caused by fly ash under a relatively low‐temperature environment but also synthesized zeolite products containing huge economic benefits.

Effects of diatomaceous earth mixing amount on the performance of curing materials for waste leachate treatment

With cement as a cementitious material, fly ash, diatomaceous earth, sugar filter mud, and river sand as materials, and waste leachate instead of water, orthogonal experiments were designed to derive the preliminary formulation of curing materials and to explore the effect of different diatomaceous earth mixing amount on the performance of curing material test blocks. The experimental results showed that as the amount of diatomaceous earth increased from 12.5% to 13.58%, the 28d compressive strength of the cured material test block decreased from 9.85 MPa to 7.35 MPa, the dry density decreased from 1012 kg/m3 to 912 kg/m3, the porosity of the test block increased from 18.94% to 23.34% and the water absorption increased from 43.91% to 66.36%. Comparison of the best formulation of curing materials selected for cement, fly ash, diatomaceous earth and sugar filter mud mass ratio of 31.09 wt.%, 51.82 wt.%, 12.94 wt.%, 4.15 wt.%, external mixing river sand 15 wt.%, with a water–solid ratio of 0.8 was added to the waste leachate to prepare the curing material test blocks.

Ge-Hg-Rich Sphalerite and Pb, Sb, As, Hg, and Ag Sulfide Assemblages in Mud Volcanoes of Sakhalin Island, Russia: An Insight into Possible Origin

We characterize the mineralogy and geochemistry of Fe, Zn, Pb, Sb, As, Hg, Ag sulfide assemblages from mud masses currently extruded by the onshore South Sakhalin and Pugachev mud volcanoes (Sakhalin Island, Russia). Abundant Tl-rich pyrite in sulfide concentrate samples from the mud volcanoes coexists with common Hg- and Ge-rich sphalerite, as well as with sporadic boulangerite, robinsonite, bournonite, galena, realgar, metacinnabar, cinnabar, acanthite, and chalcopyrite. Sphalerites are remarkably enriched in Hg (locally reaching 27 wt%) and coupled zwith permanent abnormal enrichment in Ge (3008–3408 ppm). According to single-crystal XRD analyses and Raman spectroscopy, both Hg-poor and Hg-rich sphalerites are single-phase (Zn,Hg)Scub compounds. Pyrite is of diagenetic origin, judging by its trace-element chemistry, particular morphology, and heavy S isotope composition. Another assemblage, composed of Pb-Sb-(Hg) sulfide minerals and lesser As, Cu, Ag, and Bi compounds, results from hydrothermal alteration and is genetically related to Neogene volcano-sedimentary rocks found among the ejecta of the mud volcanoes. The composition of impurities in sphalerite from mud masses indicates crystallization at temperatures lower than ~100 °C, under the leaching effect of mud volcano waters.

An analytical model for mass transport calculations in a viscous muddy layer

This study aims to present analytical solutions to the interactions between waves, currents, and the muddy bed layer and compare the results for different constant, linear, and second-order current profiles. The effects of mean shear stress and its variations on wave dispersion relations as well as mud (particle and mass transport) velocities are investigated. It is found that the second-order profile presents the maximum effects on the wave field (wave dissipation and mud mass transport velocities) compared to the constant and linear current profiles. However, assuming the constant current profile, frequently applied in the literature models, results in the minimum effects. A local peak exists in the mud mean discharge over the current profile curvature. The mud velocity induced by the linear current profile presents the closest value to the particle velocity for the no-current case. Additionally, the second-order current profile provides slightly better results for the mud mass transport velocity rather than the constant current profile when comparing the results with the laboratory data.

Numerical simulation of the water surface movement with macroscopic particles on movable beds for inhomogeneous relief

ABSTRACT In the proposed work, a numerical model of the water flow during dam breakthrough using the volume of fluid (VOF) method is constructed. The mathematical model consists of a system of Navier–Stokes equations, and also includes equations for the phase and motion of particles. For the simulation, the SST k−ω turbulent model was used. To solve the system of equations, the PISO algorithm was used. The reliability and accuracy of the developed 3D model were validated using a laboratory experiment on the problem of dam-break. The obtained results of the problem were compared with the calculations of other authors and with experimental data. The comparisons show good consistency and generally yielded positive results. Also in this work, the natural mudflow was maximally close to reality: with the presence of both deposits of mud mass and imitating particles and dam fragments of particles in an obstacle of a trapezoidal shape.

An Analytical Study on Wave-Current-Mud Interaction

This study aims at providing analytical investigations to the first and second-order on the wave–current–mud interaction problem by applying a perturbation method. Direct formulations of the wave–current–mud interaction could not be found in the literature. Explicit formulations for the particle velocity, dissipation rates, and phase shift in the first order and the mass transport in the second-order have been obtained. The findings of the current study confirmed that by an increase in the current velocity (e.g., moving from negative to positive values of current velocity), the dissipation rates and mud (instantaneous and mean) velocity decrease. The proposed assumption of a thin mud layer (boundary layer assumption) matches with the laboratory data in the mud viscosity of the orders of (0.01 N/m2) in both wave dissipation and mud mass transport leading to small ranges of discrepancies. The results from the newly proposed model were compared with the measurements and the results of an existing model in the literature. The proposed model showed better agreements in simulating the mud (instantaneous and mean) velocity compared to the existing one.

Onshore mud volcanoes as a geological source of mercury: Case study from the Kerch Peninsula, Caucasus continental collision zone

Three mud volcanoes (MVs) in the Kerch Peninsula were studied as a geological source of mercury. The study focused on total mercury (THg) concentrations in MV waters, mud masses and plants colonizing MV areas; gaseous elemental mercury (GEM) in the atmosphere above MVs; and sulfide mercury (HgS) and HgCl2 species in representative samples of mud masses. THg concentrations in the illite-smectite mud masses ranged from 38 to 920 ng/g. They contained up to 70% of total mercury in sulfide form (in pyrite and cinnabar), but lacked HgCl2. THg values in MV waters of HCO3-Cl/Na- and/or Cl-HCO3/Na-types with рН = 7.4–9.5 mostly fell in a range of 79–440 ng/L, but rarely exceeded 600 ng/L, being comparable with those for geothermal systems. Another issue of interest was the distribution of THg in below- and above-ground parts of halophyte plant Limonium caspium. THg was incorporated into the plant roots, leaves and flowers; the roots exhibited higher concentrations of THg relative to the other organs. The Hg bioaccumulation factor ranged from 0.06 to 0.76. GEM concentrations measured over large bubbling MV pools and newly formed cracks showed values (50 to 520 ng·m−3) higher than background values (≤3 ng·m−3) associated with pristine test sites and background values measured within three MV areas of the Kerch peninsula that is slightly higher than background concentration for the Northern Hemisphere. Maximum GEM contents were comparable with the values found in geothermal and magmatic volcanic provinces.

Enhancing Pb Removal and Synthesizing Glass–Ceramics from Waste CRTs Funnel Glass by Red Mud

In this paper, a novel and effective process for removing lead and synthesizing glass–ceramics from the hazardous waste CRTs funnel glass and red mud was developed. Glass–ceramics was produced through an appropriate sintering treatment of the residual glass after lead from funnel glass was removed. Vacuum smelting results showed that the addition of red mud had contributed to enhance Pb removal from funnel glass as compared to the same process without red mud. When the red mud mass was added 60 wt%, more than 99.93% of Pb was successfully removed and the Pb content was reduced to 0.0093 wt%. Metallic lead with 99% purity was recycled. The sintering process showed that the CaO–Al2O3–SiO2 type glass–ceramics were synthesized with different microstructure crystallinity and morphology. Overall, the results demonstrated that red mud can not only enhance PbO removal from waste CRT funnel glass, but also fabricate glass–ceramics combining residual glass. Route of removing Pb and synthesizing glass–ceramics from waste CRTs funnel glass by red mud.

ХАРАКТЕРИСТИКА РАСПРЕДЕЛЕНИЯ ПРОРЫВОВ ГЛИНИСТЫХ ОТЛОЖЕНИЙ В ГОРНЫЕ ВЫРАБОТКИ ИЗ ВЫШЕЛЕЖАЩИХ ОСАДОЧНЫХ ПОРОД

Актуальность. Прорывы воды и обводненных осадочных масс в горные выработки представляют серьезную угрозу для добычи полезных ископаемых подземным способом. За последние два десятка лет на шх. «Соколовская» произошел ряд аварий, связанных с прорывами глинистых масс в выработанное пространство. Самая масштабная из них привела к гибели двух человек, на восстановление рудника ушло несколько месяцев. Цель: определение источников повышенного водного питания зоны обрушения для снижения риска прорывов обводненных глинистых масс на горизонты выпуска в условиях производства работ под водоносными горизонтами осадочного чехла. Методы: анализ прорывов отложений, произошедших за период с 2003 по 2017 гг. В качестве критерия классификации используется объём глинистых пород, проникающих в горные выработки во время отдельного зарегистрированного прорыва. Выявление особенностей пространственного и временного распределения классифицированных аварий. Геостатистический анализ параметров водоносных горизонтов. Сопоставление параметров водоносных горизонтов и распределения аварий. Результаты. Основная часть крупных прорывов приурочена к очистным работам на нижних рабочих горизонтах, в области обрушения северной и центральной групп воронок. Прорывы происходят, как правило, во время начальной стадии отработки рудного тела на нижнем горизонте, в дальнейшем их частота и объем снижаются. Необходимым условием формирования масштабных прорывов является повышенная обводненность области обрушения. Источниками повышенного питания групп воронок центральной и северной являются области высоких остаточных водяных столбов Мелового водоносного горизонта на севере и западе. Основным путем снижения прорывов является рациональная организация осушения массива пород вмещающего месторождения, направленная на целевое осушение обводненных участков Мелового горизонта.

Trace element and isotopic features of carbonates from the mud volcanic ejecta from the Kura depression (Azerbaijan)

A collection of veins and dispersed Ca carbonates from the mud volcanic ejecta from Azerbaijan has been studied. The appearance of calcite veins healing cracks are divers. Isotopic characteristics of the majority of Ca carbonates are the follows: δ13С (from -4 to +2‰) and δ18О (from +20 to +26‰) and are typical of marine carbonate sediments. The fragments of vein calcite enriched in 12C (δ13С from -49.2 to -6‰) were found in the mud masses of a few mud volcanoes and might be connected with the dormant methane seeps, occurring at the high level of Caspian Sea. The dispersed Ca carbonates from mud masses have δ13С from -6.1 to +11.9‰, and δ18О from +23.8 to +32.7‰. Studied carbonates have no geochemical links with the mud volcanic waters of current emission. The aqueous fluids are characterized by high НСО3- contents (up to 8 g/l) and average δ13С(TDIC) and δ18О(Н2О) values as high as δ13С = +20.0‰ and δ18О = +4.0‰. Both isotopic and REE signatures of vein calcites allows one to connect them with post-depositional interaction between formational waters and carbonate sedimentary matter. On the base of these data mud volcanic feeder channels have been considered as isolated hydrodynamical systems, avoiding the connection with the aquafers of host sedimentary strata.

Effect of Molding Method on the Properties of Prepared Quartz Sand Sintered Brick Using the River Sand

In order which aim to save land resource and use low grade nature resource to realize high cost performance product. In this paper, the molding method of quartz sand fired brick is discussed. As the plastic (hand pressing) is only used to manually beat the mud mass, the sludge is squeezed by hand. Into the mold and molding and cold isostatic pressure molding pressure of 100 MPa, The difference is far away, which makes the gaps between the particles close to each other greatly different, the pressure of hand-press molding is small, the voids in the blank after molding are large and the hole diameter is large, and the green compact density of the brick body is small. The compact densities of the 65MPa and 150MPa pressed brick bodies are all lower than 100MPa, but 150MPa is still denser than 65MPa. The compressive strength is first increased and then decreased with increasing the molding pressure, when the pressure is 100 MPa, the maximum compressive strength is achieved at 100 MPa achieves the highest point.

A study on mud particle velocities and mass transport in wave-current-mud interaction

The upper fluid mud layer in muddy environments absorbs wave energy and, in turn, moves due to the wave action. In addition to these two major phenomena of wave-mud interaction, introduction of current in the wave field also changes the wave characteristics as well as the rates of mud mass transport. The present study offers an experimental investigation of wave-current-mud interaction to address the wave transformation and mud mass transport on a horizontal bed. A number of laboratory tests were conducted to measure the mud particle velocities as well as wave attenuation rates under following, opposing, and no current conditions. Both the wave energy dissipation and mud mass transport increase with the presence of opposing currents and decrease when following currents are introduced. A semi-analytical model was also presented and the numerical results are compared with the laboratory experiments, showing acceptable agreements.

Experimental Research on the Bond-Slip Behavior of Red Mud Concrete Filled Square Steel Tubes

In order to study the bond slip behavior of red mud concrete-filled square steel stubs, fifteen red mud concrete filled square steel tubes short column specimens were designed for the push-out test. Five parameters including replacement rate of red mud mass, concrete strength, embedment length, length diameter ratio, width to thickness ratio were regarded as variable parameters in the experiment. Through experiment, the load-slip curves of red mud concrete filled square steel tubes were obtained and analyzed.The results show that the load slip curves of red mud concrete filled square steel tubes can be classified into five stages: no slipping section, ascending section, descending section, re-ascending section and re-descending section.The bond strength increases first and then decreases with the increase of red mud substitution rate.When the substitution rate of red mud is 5%, the bond strength reaches the maximum. When the substitution rate of red mud is 20%, the bond strength is equivalent to that of normal concrete filled steel tube.