Morphogenesis of the Closed Depressions in Middle Atlas: Case of the Causse of El Menzel, Morocco

Closed depressions are the most typical exokarstic forms of the Moroccan Middle Atlas karst. These features present a great diversity of forms and sizes related to the multiple and often obscure conditions of morphogenesis in several karstic plateaus of the tabular Middle Atlas such as that of El Menzel. This little-known carbonate panel is characterized by an important geodiversity of closed depressions with variable shapes and reliefs: poljes, uvalas, dolines, kamenitzas, and rain pits. The results confirm the tectogenetic nature of several closed depressions of which the most important are: the polje of El Menzel and the polje of Quaçbat Beni Yazgha which are aligned along the major accidents of the Causse oriented NE-SW and NW-SE. The pre-established tectonic heritage Accident Median Moyen Atlasique and Accident Nord Moyen Atlasique, and the compressive tectonics and particularly extensive phases from the upper Miocene to Quaternary during the surrection of the Middle Atlas associated with the pluvial climatic phases have permitted the development of the good potential of karstification as well as the large closed depressions of the Causse

Coupling Field Investigations with the Contribution of Remote Sensing and GIS for the Moroccan Middle Atlas Karst: A Case Study of the El Menzel Causse

Little work has been done on the processes that control karstic phenomena in the Causse of El Menzel. This carbonate section of the Moroccan tabular Middle Atlas has undergone significant karstification due to favorable conditions that contribute to good karstification potential. Our field and remote sensing results confirm the tectogenetic nature of a set of expressions found in the Causse. The maps produced show good agreement between the structural, fluvial, and karstic network, given that the large NE-SW oriented faults in the sector played an inhibiting role in the triggering of karstic processes during the different phases of the Alpine cycle and neotectonics: on the one hand by the fact of weakening the liasic carbonate series sensitivity to dissolution at faulted zones and on the other hand by guiding the action of the external phenomena causing incision and fluvial erosion, forming a system of valleys which simultaneously coincides with the genesis of the karstic forms found in the Causse of El Menzel

Applying Remotely Sensed Imagery to Extract Geological Lineaments South Rifian Ridges, Morocco

The South Rifain ridges are an example of tectonic-sedimentation interaction in the Mio-Plio-Quaternary foreland basins at the front of the Rif chain. is an elongated mountain zone-oriented E-W and N-S, forming the most frontal part of the Rif belt. The morphotectonic study carried out in this area is based on Landsat-8 OLI image processing techniques to determine the contribution of these images to structural mapping. The results obtained reveal a predominant E-W orientation, which is widely present throughout the study area. This is followed by a second N-S direction, a third NW-SE direction, and a fourth NE-SW direction. The NW-SE lineaments are also mapped in kilometres. Their equivalent on the ground shows a sinister movement but does not show a significant horizontal displacement of more than a few metres. Together with the NE-SW faults, these faults form a conjugate system of dextral and sinistral faults, compatible with a palaeostress field where the maximum shortening stress is submeridian

Impact of anthropogenic activities on the physicochemical and bacteriological quality of water along Oued Fez River (Morocco)

The current study focuses, on Oued Fez, the tributary of Sebou River, the principal hydraulic artery of Fez city, to establish a spatiotemporal diagnosis from upstream to downstream. Samples were taken in 9 stations, distributed to areas with different activities (agricultural, urban and industrial), during three seasons, to evaluate the physicochemical parameters; temperature, pH, electrical conductivity (EC), dissolved oxygen (DO), turbidity, total dissolved substances (TDS), orthophosphate (PO43−), chemical oxygen demand (COD), biological oxygen demand (BOD5), nitrates (NO3−), ammonium (NH4+), nitrites (NO2−) and sulfate (SO42−). Bacteriological characterization of total aerobic microbial bacteria (TAMB), Staphylococcus aureus, Total coliforms (TC), and fecal coliforms (FC) of different samples, were carried out by standard methods. The results showed that the values of all parameters varied significantly (p < 0.05), from upstream to downstream except for; PO43−, NO3−, NO2−, and SO42−. In addition, they exceeded Moroccan water standards of surface and those of the WHO, reflecting a deterioration in the water quality along the segment studied. The high values of the physicochemical indicators and the intense microbial load resulted from the anthropic activities associated with the industrial impacts generated by the agglomerations of Fez city and those who dwell along the river, leading to the affectation of the water quality. The results of this study can offer a crucial information to municipal water operators, local authorities, and decision-makers in finding an adequate environmental approach to limit the constraints on the site and protect the integrity of its ecosystem