The Middle Atlas Geological karsts forms: Towards Geosites characterization

International audienceRich limestone Jurassic formations and huge water reservoir are natural characteristics of the Middle Atlas Chain in Morocco, which, therefore, offers geodiversity of karst geosystems. The geological, tectonic and hydro-geo-morphological nature of the history of Atlas orogeny has affected the eastern part of the Middle, ensuring the evolution of karst features on various sites of this zone. This study presents some touristic offers specific to the Middle Atlas, particularly in terms of genesis, structures, and functions that could develop and promote public tourism offers. It argues that this development depends on future geological funds identification and classification as Geosites. On the basis of the patrimonial process characterising the Middle Atlas, this study suggests the creation of a Geopark in the Middle Atlas, within the framework of the evaluation criteria of the UNESCO. The implementation of this suggestion would contribute to the socioeconomic development of this region of Morocco

Morphotectonic evolution of the Jebel Bou Naceur in the South Middle Atlas Fault Zone (Morocco)

International audienceIn eastern Morocco, fault-related folds develop above the South Middle Atlas fault that separates the J. Bou Naceur 'pop-up' structure and the Missour Basin, filled with alluvial sediments. Using a combination of surfaces, field observations and digital topographic information, we have investigated several geomorphic criteria and geometry of depositional surfaces governed by the relief's growth. The propagation of the deformation is recorded by warped segmented fans that moved southeastward and wellpreserved geomorphological features of tectonic origin. Uplift of the anticline hinges and acceleration of valley incision since the Late Pliocene are considered a consequence of the ongoing NW-SE convergence between Africa and Eurasia. A scenario of morphotectonic evolution of this active mountain front is proposed

The Middle Atlas Geological karsts forms: Towards Geosites characterization

Rich limestone Jurassic formations and huge water reservoir are natural characteristics of the Middle Atlas Chain in Morocco, which, therefore, offers geodiversity of karst geosystems. The geological, tectonic and hydro-geo-morphological nature of the history of Atlas orogeny has affected the eastern part of the Middle, ensuring the evolution of karst features on various sites of this zone. This study presents some touristic offers specific to the Middle Atlas, particularly in terms of genesis, structures, and functions that could develop and promote public tourism offers. It argues that this development depends on future geological funds identification and classification as Geosites. On the basis of the patrimonial process characterising the Middle Atlas, this study suggests the creation of a Geopark in the Middle Atlas, within the framework of the evaluation criteria of the UNESCO. The implementation of this suggestion would contribute to the socioeconomic development of this region of Morocco

Cybersecurity in the Context of Moroccan Energy Companies

The aim of this research is to assess the level of maturity of Moroccan companies in the energy sector in terms of cybersecurity and to identify the factors influencing their abilities to implement effective security measures to address the risks associated with cyber-attacks. To achieve this, we have adopted an exploratory approach. A questionnaire was sent to energy sector companies in Morocco to investigate their cybersecurity practices. This entails examining the current security measures in place, security policies and procedures, as well as employee training programs. Furthermore, we are exploring the human and financial factors that can influence the ability of energy companies to implement effective security measures against cyberattacks. The results clearly indicate that most of these companies demonstrate a high level of maturity in terms of cybersecurity. However, several significant factors influence their ability to implement effective security measures. Among these factors, the lack of qualified personnel, the high costs associated with acquiring and implementing security technologies, as well as expenses related to training and awareness, can be mentioned

Mise en évidence d’un Sénonien gypseux sous la série phosphatée du bassin des Ouled Abdoun: Un nouveau point de départ pour l’origine des zones dérangées dans les mines à ciel ouvert de Khouribga, Maroc

In the Ouled Abdoun sedimentary basin (Morocco), the phosphatic series is composed of regular interbedded phosphatic and marly limestone layers. Exploitation of the phosphate in some deposits in this basin collides frequently with problems bound to the existence, in the phosphatic series, of disturbed areas (sterile bodies) qualified as derangements by the mining engineers of the Office Cherifian Phosphate Group (OCP). Their presence in the phosphatic layers causes two kinds of problems: (1) since the whole phosphatic sequence is overlain by a Quaternary cover, we do not know their volume proportion in the phosphatic layers, and therefore the reserves estimations can be wrong (2) they are generally hard, so they complicate the phosphate extraction. Indeed, in an area containing sterile bodies, boring grid may always be tightened and boreholes filled with dynamite. The required borehole tools and use of explosives are time consuming and therefore increase drastically the cost of phosphate extraction. Their localisation would permit the mining engineers to get around them during the exploitation. Several geophysical works have carried out in the achieved in Khouribga area to localize and delimit these sterile bodies. Electric resistitivy was established as a suitable geophysical parameter to map them, but the slowness and difficulty of data collection hinders the application of these geophysical methods to the whose phosphatic deposits area (about 25000 ha). Their application in all the Ouled Abdoun basin requires the comprehension of the origin of the sterile bodies, in order to specify their formation process and to predict consequently their spacial distribution in each phosphatic deposit. Our study concerns to sedimentological and diagenetic analysis of disturbed aereas and their immediate vicinity. It made it possible to identify for the first time the existence of an evaporitic series intensely karstified at the top of the Senonian, under the phosphatic series. The senonian karsts are undoubtedly at the origin of the derangements, which are defined as the collapsing phenomena at the base of underground cavities. These bodies have a polyphase structuring and a genesis that is the consequence of on several processes (fracturing, infiltration, dissolution, collapse). Their installation began from the end of Senonian, and continues up to the Quaternary.[fr] Dans le bassin sédimentaire des Ouled Abdoun (Maroc), la série phosphatée est formée d’une intercalation régulière de niveaux phosphatés et marno-calcaires sur environ 50m de puissance. Localement, cette régularité est perturbée par la présence fréquente de structures communément appelés «dérangements». Il s’agit de masses non stratifiées, stériles, qui perturbent et alourdissent les travaux d’exploitation des couches phosphatées. Les études géophysiques expérimentales, réalisées dans les zones dérangées de la série phosphatée, ont démontré la possibilité de les cartographier sous couvertures à l’échelle décamétrique. Leur généralisation sur toute la superficie du bassin des Ouled Abdoun, nécessite une compréhension du phénomène à l’origine de ces structures. Notre étude concerne l’analyse sédimentologique et diagénétique des zones dérangées et de leur voisinage immédiat. Elle a permis d’identifier pour la première fois l’existence d’une série évaporitique intensément karstifiée au sommet du Sénonien, sous la série phosphatée. Les karsts sénoniens sont incontestablement à l’origine des dérangements ou fontis que l’on défini comme étant des phénomènes de collapses à l’aplomb de cavités souterraines. Ces fontis ont une structuration polyphasée et une genèse au dépend de plusieurs processus (fracturation, infiltration, dissolution, effondrement). Leur mise en place a débuté dès la fin du Sénonien et s’est poursuivie jusqu’au quaternaire

Geodinámica de las cordilleras del Alto y Medio Atlas : síntesis de los conocimientos actuales

Se presenta una síntesis geodinámica de las cadenas de intraplaca del Alto y Medio Atlas de Marruecos. Estas cadenas derivan de la inversión tectónica de cuencas extensionales Jurásicas, con un acortamiento orogénico modesto (máximo del 24% en el Alto Atlas y del 10% en el Medio Atlas) heterogéneamente distribuido en el tiempo y en el espacio. Las relaciones entre tectónica y sedimentación en el margen sur del Alto Atlas indican que la deformación compresiva tuvo lugar entre el Eoceno medio y el Cuaternario. Consecuentemente con los valores de acortamiento, el espesor de la corteza detectado por gravimetría no supera los 40 km. A pesar de ello, la topografía de las cadenas del Atlas es elevada, y el modelado de campos potenciales sugiere que está causada por un marcado adelgazamiento litosférico, independiente de la tectónica compresiva regional. Un abundante magmatismo alcalino indica que el adelgazamiento litosférico coexistió con el acortamiento en los últimos 15 Ma, aunque los indicadores geomorfológicos sugieren que la mayor parte del levantamiento de origen mantélico es relativamente reciente (últimos 5 Ma). La termocronología indica que la cantidad de erosión es generalmente pequeña en el Atlas, registrándose de manera notable solo en los últimos 20-25 Ma

Mean Arterial Pressure Change Associated with Cerebral Blood Flow in Healthy Older Adults

We investigate over a 12-year period the association between regional cerebral blood flow (CBF) and cardiovascular risk factors in a prospective cohort of healthy older adults (81.96 +/- 3.82 year-old) from the Cognitive REServe and Clinical ENDOphenotype (CRESCENDO) study. Cardiovascular risk factors were measured over 12 years, and gray matter CBF was measured at the end of the study from high-resolution magnetic resonance imaging using arterial spin labeling. The association between cardiovascular risk factors, their long-term change, and CBF was assessed using multivariate linear regression models. Women were observed to have higher CBF than men (p < 0.05). Increased mean arterial pressure (MAP) over the 12-year period was correlated with a low cerebral blood flow (p < 0.05, R(2) = 0.21), whereas no association was detected between CBF and MAP at the time of imaging. High levels of glycemia tended to be associated with low cerebral blood flow values (p < 0.05). Age, alcohol consumption, smoking status, body mass index, history of cardiovascular disease, and hypertension were not associated with CBF. Our main result suggests that change in MAP is the most significant predictor of future CBF in older adults

Crustal thickness and velocity structure across the Moroccan Atlas from long offset wide-angle reflection seismic data: The SIMA experiment

The crustal structure and topography of the Moho boundary beneath the Atlas Mountains of Morocco has been constrained by a controlled source, wide-angle seismic reflection transect: the SIMA experiment. This paper presents the first results of this project, consisting of an almost 700 km long, high-resolution seismic profile acquired from the Sahara craton across the High and the Middle Atlas and the Rif Mountains. The interpretation of this seismic data set is based on forward modeling by raytracing, and has resulted in a detailed crustal structure and velocity model for the Atlas Mountains. Results indicate that the High Atlas features a moderate crustal thickness, with the Moho located at a minimum depth of 35 km to the S and at around 31 km to the N, in the Middle Atlas. Upper crustal shortening is resolved at depth through a crustal root where the Saharan crust underthrusts the northern Moroccan crust. This feature defines a lower crust imbrication that, locally, places the Moho boundary at 40-41 km depth in the northern part of the High Atlas. The P-wave velocity model is characterized by relatively low velocities, mostly in the lower crust and upper mantle, when compared to other active orogens and continental regions. These low deep crustal velocities together with other geophysical observables such as conductivity estimates derived from MT measurements, moderate Bouguer gravity anomaly, high heat flow, and surface exposures of recent alkaline volcanism lead to a model where partial melts are currently emplaced at deep crustal levels and in the upper mantle. The resulting model supports the existence of a mantle upwelling as mechanism that would contribute significantly to sustain the High Atlas topography. However, the detailed Moho geometry deduced in this work should lead to a revision of the exact geometry and position of this mantle feature and will require new modeling effortsThis work has been primarily funded by the Spanish MEC project CGL2007–63889. Additional funding was provided by projects CGL2010–15416, CSD2006-00041, and GL2009–09727 (Spain), CGL2008–03474-E, 07-TOPO_EUROPE_FP-006 (ESF Eurocores) and EAR-0808939 (US, NSF).Peer reviewe