Groundwater Potential Assessment Using Vertical Electrical Sounding and Magnetic Methods: A Case of Adilo Catchment, South Nations, Nationalities and Peoples Regional Government, Ethiopia

Vertical electrical sounding and magnetic methods were carried out to assess groundwater potential in Adilo catchment, Kembata Tembaro Zone, South Nations, Nationalities and Peoples Regional Government, Main Ethiopian Rift. The data were acquired from eight VES points using Schlumberger electrode arrays with maximum half current electrode spacing ( AB / 2 = 500 ) and 253 magnetic data points were analyzed. The qualitative analysis of VES data was accomplished by using curves, apparent resistivity, and pseudodepths, and the quantitative interpretations of the VES data were constructed by the VES data using IPI-Res3, IPI2Win, and surfer software and constructing geoelectric section along with profiles and lithological information from the borehole and Geosoft interpretation was used for magnetic data. The VES results of the data revealed five geoelectric layers which differ in degree of fracturing, weathering, and formation. The upward continued magnetic field map anomaly to 560 m illustrated northwestern to the southwest; areas have a low magnetic anomaly. Examining the potential aquifer of profile one’s geoelectric section, the horizons of layer four were better potential aquifers as the highly fractured and weathered ignimbrite zone of layer five of VES13 was 219 m deeper than the depths of the other VES points, and along with profile two geoelectric sections, the horizon of layer four VES23 layer five has the lowest resistivity with large thickness at a depth of 253 m. Thus, the low resistivity and the large thickness of these formations are an indication of the high yield of groundwater potential in the study area.

Tracking Airborne Pollution with Environmental Magnetism in A Medium-Sized African City

As in other parts of the world, air pollution over West and Central Africa has major health and meteorological impacts. Air quality assessment and its possible sanitary impact have become essential even in medium-sized towns, therefore amplifying the need for easy-to-implement monitoring methods with low environmental impact. We present here the potential of magnetic methods to monitor air quality at street level in the medium-sized city of Maroua (northern Cameroon) affected by dust-laden desert winds. More than five hundred (544) samples of bark and leaves taken from Neem trees in Maroua were analyzed. Magnetic susceptibility, saturation remanence, and S-ratio were found to determine the concentration and nature of magnetic particles. They are dominated by magnetite-like particle signals as a part of particulate emissions due to urban activities, including both traffic, composed of a substantial proportion of motorcycles, and wood burning for food preparation. We show that both bark and leaves from Neem trees are adequate passive bio-recorders. The use of both enables different times and heights to be sampled, allowing for the high-resolution monitoring, in terms of spatialization, of various urban environments. Particle emissions require assessment and screening that could be carried out rapidly and efficiently by magnetic methods on bio-recorders, even in cities impacted by dust-laden wind.

Characterization of High-Temperature Superconductor Bulks for Electrical Machine Application

High-temperature superconducting (HTS) bulks can be used in electrical applications. Experimental characterization of large-size HTS bulks is a tricky issue. The relevant parameters for their application were directly measured in this study. This paper has three main aims. Firstly, features of YBaCuO bulks are presented. Secondly, an electrical motor application is developed using magnetic field shielding and trapping. Thirdly, the HTS bulks are characterized. Several classical methods were used, which are mainly magnetic methods only available for small samples. The complete penetration magnetic field and the critical current density were found to be the main parameters relevant for applications. An innovative entire HTS bulk characterization method is presented. This characterization method is useful for end users and engineers to better implement HTS bulks.

Magnetic properties of PM in indoor/outdoor domestic environments

<p>The finer fraction of the particulate matter (PM) is the most harmful health wise, as it has more capacity to reach deeper parts of the respiratory system. Among other constituents, PM also contains iron oxides, allowing for the use of magnetic methods in its investigation as proxies for the whole of PM. Those methods present advantages in comparison to traditional ones, being quick, cost effective and sensible to investigate iron oxides among PM. </p><p>To better understand the risks related to PM exposition in the domestic context, the assessment of magnetic parameters may be used in outdoor and indoor environments, giving us information on the concentration of iron oxides (and consequently, PM) and its dispersion from one environment to the other. </p><p>We developed a citizen sciences experiment in the city of Toulouse, France. Tree barks were used as bio-collectors. Garlands composed of tree bark pieces were distributed to the population in May-2019, and placed in both indoors and outdoors of flats and homes to capture PM. They were retrieved after one year. Measurement of magnetic susceptibility, ARM, SIRM, S -ratio and estimation of superparamagnetic concentration were performed. A total of 86 bio-collectors kits were successfully analyzed. The preliminary results indicate a higher concentration of iron oxides outdoors, with a mean difference between outdoor and indoor measurements of 6.58x10<sup>-9</sup>m<sup>3</sup>/kg and 1.38x10<sup>-5</sup>Am<sup>2</sup>/kg in susceptibility and SIRM respectively. The concentration of the SP fraction also follows this trend of higher outdoor values. The magnetic mineralogy is mostly dominated by low coercivity magnetite-like carriers.</p><div> <div> <div> </div> </div> <div> <div> </div> </div> </div>

Multi-proxy study of the Cretaceous-Paleogene (K-Pg) boundary in deep-sea turbiditic sediments in the Uzgruň section (Outer Flysch Carpathians, Czech Republic)

<p>The composite profile, with 4 studied sections, is located near the Uzgruň village (Czech Republic) next to a small stream. The profile is composed of Late Maastrichtian to Palaeocene flysch sediments and the K-Pg boundary is set in claystones within this turbiditic setting. Ongoing research of local paleoenvironment and stratigraphy is based on paleo- and rock-magnetic methods, micropaleontology and geochemistry to obtain more detailed view of the local situation during the K-Pg extinction event. Based on biostratigraphy, two dinocyst zones (Bubík et al., 2002): Palynodium grallator and Carpatella cornuta (first occurrence in the Danian), two calcareous nannofossil zones in the Upper Maastrichtian, and the agglutinated foraminifer zone Rzehakina fissistomata in the Paleogene were distinguished. Biostratigraphic data support the K-Pg boundary interval. The uppermost Maastrichtian is indicated by nannofossil species Micula prinsii, UC26d<sup>TP</sup> zone. Basal Paleogene non-calcareous strata contain dinocyst Carpatella cornuta and agglutinated foraminifers of Rzehakina fissistomata zone. The presence of low-latitude nannofossil taxa M. prinsii and Ceratolithoides kamptneri show input of warm waters during the uppermost Maastrichtian. Several rock-magnetic methods, such as acquisition of Isothermal remanent magnetization (IRM), acquisition of Anhysteretic remanent magnetization (ARM), Anisotropy of magnetic susceptibility (AMS), Field dependence of magnetic susceptibility (HD) and Frequency dependence of magnetic susceptibility (FD), were applied to estimate behaviour and origin of magnetic particles. Natural remanent magnetization (NRM) values of samples range from 0.09 to 2.48 mA/m. Volume normalized magnetic susceptibility (MS) show values from 130 up to 1197 SI*10-6. There is no increase observed in MS across stratigraphic boundary due to turbiditic evolution of sediment. Due to character of sediments, we applied alternating field (AF) demagnetization and used principal component analysis (PCA; Kirschvink, 1980) for estimation of characteristic remanent component. Most of the K/Pg sections worldwide have well documented Iridium anomaly. In Uzgruň, the preliminary results show that although the values are not as pronounced, the Ir at K-Pg boundary is still higher than in surrounding sediments. For tracing of Deccan traps effect we plan to apply mercury (Hg)/total organic carbon (TOC) stratigraphy. TOC content of 20 pilot samples is low, but not under detection limit of the instrumentation (mean value 0.92 wt%). One sample reached value 4.41 wt% of TOC. Sulphur contents are reaching 1 wt%, but several samples were under detection limit of the instrumentation. Sulphur concentrations suggest more reduction conditions of burial.</p><p>Current research is supported by Czech Science Foundation project no. 19-07516S and is in accordance with research plan no. RVO67985831.</p><p>Bubík, M., Adamová, M., Bąk, M., Franců, J., Gedl, P., Mikuláš, R., Švábenická, L., & Uchman, A. (2002). Výsledky výzkumu hranice křída/terciér v magurském flyši u Uzgruně. Geologické výzkumy na Moravě a ve Slezsku, 9, 18–22</p><p>L. Kirschvink (1980), The least-squares line and plane and the analysis of palaeomagnetic data, Geophysical Journal International, 62(3), 699–718, https://doi.org/10.1111/j.1365-246X.1980.tb02601.x</p>