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Abstract This study interprets aeromagnetic data from the Tizi n'Test area in the High Atlas massif of Morocco, aiming to gain insights into its litho-structural architecture and implications for mineral exploration and mining. We employed six different analytical techniques to the residual magnetic field data, including reduction to the pole (RTP), upward continuation, total horizontal derivative, Tilt angle, Centre for Exploration Targeting (CET) analysis, and Euler deconvolution. Our analyses differentiated the study area into three magnetic domains: the eastern Ouzellarh block, characterized by positive anomalies, a central domain characterized by a negative magnetic signature demarcating the transitional zone between the Anti-Atlas and the High Atlas separated by the Ouchden fault: and the western domain, represented by the Tichka massif. The application of total horizontal derivative, tilt angle, and a combination of filters in ternary image formats (Tilt angle, upward continuation 1000 + Tilt angle and upward continuation 3000 + Tilt angle) revealed both known and previously unidentified geological lineaments, mapping structural complexity across various orientations (NE–SW, NNE–SSE, E–W, NW–SE, and N–S). The CET grid analysis method unveiled the structural complexity, highlighting the geodynamic evolution of the region. Particularly, the Ouchden fault delineates a magnetic domain divide between the ancient High Atlas and the Ouzellarh block (Anti-Atlas). Furthermore, Euler deconvolution indicated magnetic source depths ranging from 52 m in the western domain of the Tichka massif to 6560 m in the Ouzellarh block. A comprehensive structural scheme, classified by C-A fractal analysis, identified zones favourable for exploration and mining, particularly along the Ouchden fault, Tizi n'Test, NE-SW trending lineaments in the northwestern domain, as well as along the Tichka granite’s margin.

The Sidi Ifni region in southwest Morocco is mainly composed of crystalline rocks with limited groundwater storage capacity. These water resources drain in particular fault zones with high fracture permeability. The main objective of this study is to describe the geological structure of the region to optimize future drilling locations. The gravity data were processed using various techniques, such as total horizontal gradient, tilt derivative, and Euler deconvolution, in conjunction with the interpretation of the geological data, to create a new structural map. This map confirms the presence of many previously identified or inferred faults and identifies significant new faults with their respective trends and depths. Analysis of this map shows that major faults are oriented NNE-SSW and NE-SW, while minor faults are oriented E-W, NW-SE, and NNW-SSE. The superposition of the hydrogeological data and the structural map reveals that the high groundwater flow values in the boreholes are located in the vicinity of the major faults and talwegs. The structures deduced from the filtering and interpretation of the gravity data suggest that the hydrogeological system of the Ifni Inlier is controlled by its structures. To confirm this impact, a high-resolution electrical resistivity map (7200 Hz) was used, with penetration depths ranging from 84 to 187 m. Negative boreholes, located in high resistivity ranges corresponding to sound basement formations without fault crossings, showed high resistivity values. The positive holes, located in anomalies with low linear resistivity, revealed the impact of fault crossings, which drain water and tend to decrease the resistivity values of the formations. Therefore, these new structural maps will assist in planning future hydrogeological studies in this area.

An assessment of potential groundwater areas in the Ifni basin, located in the western Anti-Atlas range of Morocco, was conducted based on a multicriteria analytical approach that integrated a set of geomorphological and hydroclimatic factors influencing the availability of this resource. This approach involved the use of geographic information systems (GIS) and hierarchical analytical process (AHP) models. Different factors were classified and weighted according to their contribution to and impact on groundwater reserves. Their normalized weights were evaluated using a pairwise comparison matrix. Four classes of potentiality emerged: very high, high, moderate, and low, occupying 15.22%, 20.17%, 30.96%, and 33.65%, respectively, of the basin’s area. A groundwater potential map (GWPA) was validated by comparison with data from 134 existing water points using a receiver operating characteristic (ROC) curve. The AUC was calculated at 80%, indicating the good predictive accuracy of the AHP method. These results will enable water operators to select favorable sites with a high groundwater potential.

During the last decade, climate change has generated extreme rainfall events triggering flash floods in short periods worldwide. The delimitation of flood zones by detailed mapping generally makes it possible to avoid human and economic losses, especially in regions at high risk of flooding. The Taguenit basin, located in southern Morocco, is a particular case. The mapping of the flood zones of this basin by the method of the Flood Hazard Index (FHI) in a GIS geographic information systems environment was based on the multi-criteria analysis, taking into consideration the seven parameters influencing these extreme phenomena, namely rainfall, slope, flow accumulation, drainage network density, distance from rivers, permeability, and land use. Average annual rainfall data for 37 years (1980 to 2016) was used in this study for floodplain mapping. A weight was calculated for each parameter using the Analytical Hierarchy Process (AHP) method. The combination of the maps of the different parameters made it possible to draw up a final map classified into five risk intervals: very high, high, moderate, lower and very lower presenting, respectively, 8.04%, 20.63%, 31.47%, 15.36%, and 24.50% of the area of the basin. The reliability of this method was tested by a Flood susceptibility analysis. The results generated by the Flood Hazard Index (FHI) model are similar to those of previous historical events. Realistic and applicable solutions have been proposed to minimize the impact of these floods as much as possible.

V zadnjih letih narašča zanimanje za beleženje in raziskovanje učinkov paleoseizmičnih dogodkov na kraškem površju in v podzemlju. Kras je lahko zanesljiva referenčna točka za razumevanje potencialne seizmičnosti na področjih, kjer opazovalni inštrumenti kažejo nizko oziroma zmerno seizmičnost. V Bolgariji in Maroku zavzema kras velike površine. Spremembe na kraškem površju in v podzemlju navadno povzročijo katastrofalni trenutni dogodki ali pa ponavljajoča se premikanja zaradi potresov. Katastrofalni potresni dogodki so spremenili medsebojno povezane kraške ekosisteme in so bili vzrok za pomlajevanje, reaktiviranje ali prekinitev kraških procesov. Naravni površinski ali podzemeljski relief sta bila deloma ali v celoti uničena; nastal je nov tip reliefa; geološko okolje je bilo spremenjeno; nastale so spremembe v količini odtoka in v smeri površinskega in podzemeljskega odtekanja kraške vode; nastali so gravitacijski tipi močvirij; kraške jame, lokalni tektonski jarki, prihajalo je do podorov in zemeljskih plazov in ozemlje je bilo podvrženo grezanju in uničenju; spremenjeno je bilo ekološko ravnotežje urbaniziranih pokrajin. V pričujočem delu je govora o različnih paleoseizmičnih pojavih na krasu v Bolgariji in v Maroku. Na podlagi preučevanja tektonskih premikov so dana priporočila za varstvo teh ozemelj. During the recent years there has been a growing interest in recording and investigating the effects of paleoseismic events in surface and underground karst in almost all countries. Karst represents a reliable reference marker for understanding the potential seismicity in regions with instrumentally established low to moderate seismicity. The karst terrains in Bulgaria and Morocco occupy considerable areas. The disturbances in surface and underground karst had usually been provoked by catastrophic one-act events or by repeatedly activated movements by earthquakes. The catastrophic seismic events had disturbed the naturally interrelated karst ecosystems and were the reason for rejuvenation, reactivation or attenuation of karst processes. The natural surface and underground relief had been partially or entirely destroyed; a new type of relief had been formed; the geological environment had been disturbed; changes occurred in the flowrate and direction of surface and underground karst water; wetlands of the gravitation type had been formed; natural caves, local grabens, rock-falls and landslides collapsed partially or entirely and terrains were subjected to subsidence and destruction; the ecological balance in urbanized territories had been disturbed. The present work considers the different types of paleoseismic phenomena in the karst terrains in Bulgaria and Morocco. Recommendations are given for the protection of these areas.

The study of both endokarstic systems Bosnek (Vitosha Mountain, Bulgaria) and Wintimdouine (High Atlas Mountain, Morocco) is presented in this work. Both regions are standard for the study of geodynamic processes in Bulgaria and Morocco, and they could be used as geodynamic polygons in the Mediterranean region. The karst is developed in Triassic and Jurassic limestones. The karst processes in both endokarstic systems occur under the conditions of active Quaternary and recent tectonics. A typical structural karst is formed. The present work shows also the results of the comprehensive studies performed in the field of geology, tectonics, geomorpholody, hydrology, climatology, etc., of the karst. It is accented on the genesis and the evolution of the greatest cave systems in Bulgaria (Duhlata cave – more than 17 km) and Morocco (Wintimdouine cave – more than 19 km long). Both cave systems are situated in zones with high seismicity, with open surface and sud-surfase paleoseismic disruptions. The karst study and monitoring of its processes has great practical value in Bulgaria and Morocco because they are related to one of the largest urbanized territories ( Pernik and Sofia for Bulgaria, and Agadir for Morocco) and they are protected natural objectives as well. V prispevku so predstavljene raziskave jamskih sistemov Bosnek (Vitoša, Bolgarija) in Wintimdouine (Visoki Atlas, Maroko). To sta standardni območji za preučevanje geodinamičnih procesov v Bolgariji in Maroku in bi lahko služili kot geodinamični poligon za celotno Sredozemlje. Tamkajšnji kras je razvit v triasnih in jurskih apnencih. V obeh jamskih sistemih potekajo kraški procesi pod vplivom aktivne kvartarne in recentne tektonike. Izoblikovan je značilni strukturni kras. V članku so predstavljeni tudi izsledki podrobnih preučevanj krasa na področju geologije, tektonike, geomorfologije, hidrologije, klimatologije, itd. Osredotočen je na največja jamska sistema v Bolgariji (preko 17 km dolga jama Duhlata) in Maroku (preko 19 km dolga jama Wintimdouine). Oba sistema sta v območju močne seizmičnosti z odprtimi površinskimi in podpovršinskimi paleoseizmičnimi razpokami. Preučevanje in redno opazovanje krasa in kraških procesov je za Bolgarijo in Maroko velikega praktičnega pomena, saj so vezana tako na največja urabnizirana ozemlja (Pernik in Sofija v Bolgariji, Agadir v Maroku), kot so to tudi zavarovani naravni pojavi.