Assessment of spatial distribution of contaminants and their levels in soil and water resources of Calabar,Nigeria using geophysical and geological data

The contamination levels of soils and water resources in Calabar, Nigeria have been investigated using resistivity (vertical electrical sounding and electrical resistivity tomography), geochemical analyses of soil and water resources and textural analysis. Sixty randomly sited VES sites were investigated in two seasons while ERT investigations were performed along four profiles. The geochemical investigations were spread across seasons in order to track seasonal changes in physico-chemical parameters: hydrogen ion concentration (pH), electrical conductivity, total dissolved solids, chloride ion (Cl^?), nitrate ion (\( {\text{NO}}_{ 3}^{ - } \)), bicarbonate (\( {\text{HCO}}_{ 3}^{ - } \)), sulphate ion (\( {\text{SO}}_{ 4}^{2 - } \)), calcium ion (Ca²⁺), sodium ion (Na⁺), potassium ion (K⁺) and magnesium ion (Mg²⁺). Additionally, concentrations of ammonium, aluminium and nitrite ions in soils were determined. Results show that ionic concentrations in the sand-dominated soils and water are within permissible limits and baseline standards. The resistivities follow known trends in the area. However, at the central waste disposal site, a localised thin (< 5 m), low resistivity (< 15 Ωm) anomaly suspected to be due to contamination by leachates was observed. Comparatively, the contaminated area is also characterised by marginal increase in ionic concentrations. Strong attenuation capacities of overlying and adjoining clay/lateritic sediments and optimal design of the waste dump site probably reduced the spread of contaminants. The contaminated zone need to be closely monitored so that it does not extend to the aquifers. Hence, all strategies presently being used in managing wastes in Calabar should be sustained.     

Soil wettability in ground engineering: fundamentals,methods, and applications

Wettability is a fundamental property controlling the extent of wetting in flat and granular solids. In natural soils, wettability affects a wide variety of processes including infiltration, preferential flow and surface runoff. In mineral processing, wettability is paramount in enhancing the efficiency of separation of minerals from gangue. The manipulation of surface wettability is equally crucial in many industrial applications. For instance, superhydrophobic surfaces are those on which water drops roll off easily and as such are used for self-cleaning applications. Therefore, while wettability is strongly cross-disciplinary, its evolution has been discipline-specific with a direct extrapolation or transfer of concepts, approaches, and methods to ground engineering unlikely to remain valid. This paper synthesizes relevant aspects from surface chemistry, materials science, mining engineering, and soil science, and discusses their implications within the context of new granular materials that resist wetting, for use in barriers or ground improvement and, in unsaturated soils, where the effects of wettability have been documented.     

Accessing effects and signals of leakage from a CO<Subscript>2</Subscript> reservoir to a shallow freshwater aquifer by reactive transport modelling

CO₂ geological storage is a transitional technology for the mitigation of climate change. In the vicinity of potential CO₂ reservoirs in Hungary, protected freshwater aquifers used for drinking water supplies exist. Effects of disaster events of CO₂ escape and brine displacement to one of these aquifers have been studied by kinetic 1D reactive transport modelling in PHREEQC. Besides verifying that ion concentrations in the freshwater may increase up to drinking water limit values in both scenarios (CO₂ or brine leakage), total porosity of the rock is estimated. Pore volume is expected to increase at the entry point of CO₂ and to decrease at further distances, whereas it shows minor increase along the flow path for the effect of brine inflow. Additionally, electrical conductivity of water is estimated and suggested to be the best parameter to measure for cost-effective monitoring of both worst-case leakage scenarios.     

Biostratigraphy and paleogeography of the southeast desert phosphorites of Jordan

Three sections from the Al-Hisa Phosphorite Formation (AHP) were measured in the southeastern desert of Jordan: Batn El-Ghoul, Nagb Etayyeg, and Zgaimat Al-Hasah. A fourth section, Wadi Arfa, is added from a previous work. The three sections differ from the typical AHP Formation in central Jordan by having highly reduced thicknesses, omission/non-deposition of the underlying formations, rarity of fossils, abundant sand, and their stratigraphic ages. A Paleocene-Early Eocene age, based on calcareous nannofossils, has been assigned to the AHP Formation of the sections studied in the southeast desert. This Paleocene-Early Eocene age is younger than the Early Maastrichtian age of the AHP deposits in central Jordan. The published ages of the phosphorite deposits in the eastern Mediterranean countries suggest a younging to the east due to an interplay between paleodepositional environments and plate tectonics (paleohigh formation). The minor phosphorite deposits of Turkey and Iran are not involved in the discussion because they were not part of the Afro-Arabian Plate or the later Arabian Plate. The abovementioned differences between the southeastern desert phosphorites and the central Jordan deposits are here explained by the formation of paleohighs on the Neo-Tethys seafloor during the Late Cretaceous-Eocene. These include the Sirhan Paleohigh where the southeast desert phosphorites were deposited. The formation of the highs was due to the compression associated first, with the subduction of the Afro-Arabian Plate, below the Eurasian Plate and later with their collision.     

Economic potentials of industrial rocks and minerals in the Azraq basin,NE Jordan

The Azraq basin (the Badia region in NE-Jordan) is rich in its industrial rocks and minerals. Most of the commodities are concentrated in one area, which is the Azraq depression (El-Qa’). The climatic changes (wet and dry) of Azraq closed lake contributed in the formation of industrial rocks and minerals in the El-Qa’. Basalt, pyroclastics, zeolites, diatomaceous earth, bentonite, palgorskite, porcelanite, saline brines, chalk, limestone, and gypsum are the potential industrial commodities. The basaltic rocks are of high alkalis content and good homogeneity and are of good potential use in constructions and cast basalt. The scoriaceous pyroclastic material proved to be of excellent properties for use as lightweight aggregates, cultivation purposes, and for the production of pozzolanic cement. Smectite-rich beds (bentonite) from Ein El Badia could be used as binder, absorbent, and additives for feeding farm animals. Palygorskite is potential for use in drilling mud, paint, pharmaceuticals, and as a filtering medium. The diatomaceous earth deposits are Moler type and could be used as filter aid and absorbent. Zeolites are efficient for agricultural purposes, animal waste, and wastewater treatment plants. Saline brine is exploited in the Azraq mudflat area for table salt. Porcelanite could be used as an absorbent of hazardous elements, abrasive, and filler. The softness and high purity of chalk enable its use as filler and in the lime production. The large limestone concretions are of high quality for use as a building stone. Gypsum (gypcrete) could be used after the removal of the undesired chert impurities. The Badia region is a highly potential area for future exploration and mining industry in a manner that achieves the required outcomes and minimizes impacts on ecosystems.     

Anisotropic Continuous-in-Scale Universal Multifractal Cascades: Simulation,Analysis and Correction Methods

Continuous-in-scale multifractal cascades has long been an attractive choice for mathematically modeling turbulent and turbulent-like geophysical fields. These fields are usually anisotropic as they are subject to both stratification and rotation, thereby questioning the isotropy assumption often made to model them. The self-affine and generalized scale invariance approaches to scaling are used here to introduce anisotropy in such models. These anisotropic simulations have (1) unresolved large-scale features and (2) statistics that deviate from the desired power-law scaling mainly in the small scales. The former issue is solved via nesting, whereas the latter is attempted to be overcome using singularity correction methods. While earlier studies have proposed isotropic correction methods, here they have been generalized to correct anisotropic simulations. These singularity corrections seem to improve the small-scale statistical properties of mildly anisotropic simulations; nesting, on the other hand, appears to enhance statistics over almost all scales even for strongly anisotropic simulations. Both the correction and nesting techniques lead to a reduction in computational time and memory usage suggesting that nested singularity-corrected cascades offer a better framework for quantitatively modeling the atmosphere, ocean, solid earth, and associated fields.     

Facies Structure and Quantitative Parameters of Pleistocene Sediments of the Bering Sea

Lithofacies zoning is described for the first time for the Neo- and Eopleistocene of the Bering Sea. Four lithofacies sedimentation zones are distinguished: (I) terrigenous; (II) siliceous–terrigenous; (III) siliceous, and (IV) volcanoterrigenous ones. Corresponding maps were treated using Ronov volumetric method to quantify sedimentation parameters for distinguished lithofacies zones (subzones) and types of Pleistocene sediments. It was revealed that terrigenous sediments predominate over other sediments. Accumulation of the terrigenous sediments was more intense (by 1.4 times) in the Neopleistocene than in the Eopleistocene. The sedimentation rate of siliceous sediments of the Bowers Ridge in the Eopleistocene was two times higher than in the Neopleistocene.