LE CRETACE SUPERIEUR DE LA REGION D’IMIN’TANOUT (HAUT ATLAS OCCIDENTAL, MAROC) : SEDIMENTOLOGIE, BIOSTRATIGRAPHIE ET ANALYSE SEQUENTIELLE

The sedimentological and biostratigraphic study of Upper Cretaceous in the region of Imin'Tanout allowed to individualize three differents senonians formations: The dolomitic limestone and marl formation of Anou-nfeg of Coniacien age, the dolomitic formation of Ait Abbes of Santonian age and the phosphatic formation of Maastrichtian age. The first formation is formed in an environment of internal platform in communication with the wide passing a coastal environment with continental influences. The second formation characterizes a tidal internal platform passing an environment of sebkha type, affected by marine incursions. The last formation is transgressive and marks the return of the sea, in a hot and arid climate

ETUDE SEDIMENTOLOGIQUE DU TRIAS ET JURASSIQUE DU HAUT ATLAS DE MARRAKECH, MAROC : CONTRIBUTION A LA LOCALISATION DES NIVEAUX FAVORABLES A L'EXPLOITATION ARTISANALE POUR LA POTERIE

The work presented here is a contribution to the localization and characterization of favorable levels to artisanal mining for pottery by geochemical analysis of the clay samples. The macroscopic and microscopic description of the different facies identified in the study area allows the interpretation of sedimentological and structural characteristics of each facies. At the outcropping, these facies are generally marked by abundant figures desiccation and the presence of traces of biological activity, reflecting a low layer of water depositional environment under a moderate to low hydrodynamic regime. The samples analysed show a relatively similar to clay geochemistry of the region of Ourika Douar Tafza. As such, we are convinced that the results presented in this work will be useful and will provide a good orientation for the future potential developmental projects

EXAMPLE OF PALEOSEBKHA LITTORAL DEPOSITS OF SENONIAN IN THE "BASINS ZONE" OF AIT OURIR (MARRAKECH HIGH ATLAS, MOROCCO)

The comparative analysis of three cuts oriented West-East at the level of the basin of Jbel Sour, led to defining during the Santonian: A western sector of detrital coarse sediments, deposited in the context of a fluvial dynamics. Oriental sector of mainly carbonato- evaporite sedimentation, in a less deep and confined environment, subject to significant subsidence under a hot, arid climate favoring the formation of sebkha facies. These santonien deposits are organized in a regressive megasequence, surmounted by a Maastrichtian transgressive formation, corresponding, in this area, to a tidal-flats environment. This Maastrichtian serie marking the return of the epicontinental sea, under a hot, arid climate, by an Atlantic transgression encompassing the entire study area

Mise en évidence d’une phase tectonique au Santonien du versant Nord du Haut Atlas Occidental, Maroc

At the level of the north hillside of the western High Atlas, only the training of limestones and dolomitic marls of Aït Abbes was recognized in Senonian. It is topped by the phosphated series. To highlight a tectonic action at the end of lower Santonian of Sidi Bou Othman's region and which is probably due to a halocinique phase, three cuts were been lifted on both sides of the Assif Aït Tabgaw. This tectonic phase appears by angular unconformity within the deposits of the training of Aït Abbes, microfaults, synsedimentary slidings, and monogenic breaches… It also structures the whole region at the high bottom or emergent low lands forming several small basins confined and supersaturated in brines. Then, following an important peneplanation, a platform of sebkha type is set up on the whole region. Some brief marine incursions reach the eastern basins

ETUDE SEDIMENTOLOGIQUE DU TRIAS ET JURASSIQUE DU HAUT ATLAS DE MARRAKECH, MAROC : CONTRIBUTION A LA LOCALISATION DES NIVEAUX FAVORABLES A L'EXPLOITATION ARTISANALE POUR LA POTERIE

The work presented here is a contribution to the localization and characterization of favorable levels to artisanal mining for pottery by geochemical analysis of the clay samples. The macroscopic and microscopic description of the different facies identified in the study area allows the interpretation of sedimentological and structural characteristics of each facies. At the outcropping, these facies are generally marked by abundant figures desiccation and the presence of traces of biological activity, reflecting a low layer of water depositional environment under a moderate to low hydrodynamic regime. The samples analysed show a relatively similar to clay geochemistry of the region of Ourika Douar Tafza. As such, we are convinced that the results presented in this work will be useful and will provide a good orientation for the future potential developmental projects

LE CRETACE SUPERIEUR DE LA REGION D’IMIN’TANOUT (HAUT ATLAS OCCIDENTAL, MAROC) : SEDIMENTOLOGIE, BIOSTRATIGRAPHIE ET ANALYSE SEQUENTIELLE

The sedimentological and biostratigraphic study of Upper Cretaceous in the region of Imin'Tanout allowed to individualize three differents senonians formations: The dolomitic limestone and marl formation of Anou-nfeg of Coniacien age, the dolomitic formation of Ait Abbes of Santonian age and the phosphatic formation of Maastrichtian age. The first formation is formed in an environment of internal platform in communication with the wide passing a coastal environment with continental influences. The second formation characterizes a tidal internal platform passing an environment of sebkha type, affected by marine incursions. The last formation is transgressive and marks the return of the sea, in a hot and arid climate

Variance-Based Fusion of VCI and TCI for Efficient Classification of Agriculture Drought Using Landsat Data in the High Atlas (Morocco, North Africa)

Drought assessment using drought indices has been widely carried out for drought monitoring. Remote sensing-based indices use remotely sensed data to map drought conditions in a particular area or region. Therefore, the objective of the present study is to make a study on drought risk based on the calculation of an indicator from biophysical parameters extracted from NOAA/AVHRR satellite data, namely TCI and VCI, to obtain a better understanding of the differentiation between each index, and their application for drought monitoring in the High Atlas of Marrakech on the Chchaoua Morocco watershed during 1980-2020. Landsat oli7 and8 data were used to construct the indices. The result showed that each index proved to be a useful, fast, sufficient, and inexpensive tool for drought monitoring. However, each index has its differences. The TCI was found to be drought sensitive during the dry season or in months when high temperatures occurred. While VCI detected drought more sensitively in the rainy season as well (December-January-February to May) than TCI and VCI. Meanwhile, VCI, including the improved TCI, combined two indicators to better understand drought occurrence. These indices were calculated using GIS, QGis, ArcGis satellite imagery scenes, and Landsat. After a comparative study of these years, from 1984 to 2020, the evolution of the VCI and TCI was highlighted

CARTOGRAPHIE PAR SIG DE L’ALÉA D’ÉBOULEMENT DANS LE BASSIN VERSANT DE DADES (HAUT ATLAS CENTRAL), MAROC

Landslides constitute the natural events which threaten the goods and the persons. They include the whole natural or man-made movements more or less rough of soil or subsoil. The Dades watershed parameters, strong topographic slopes, lithology, geological structure and vegetation cover, make it an unstable and sensitive area of landslides. The magnitude of this phenomenon was most remarkable in the upstream part and plays a key role of basin evolution. In this work the landslide term include the rock slides of rock masses of various sizes which, mainly manifest in the carbonate and conglomerates formations respectively of Jurassic and Mio-Pliocene age, and seriously threaten the homes and the road network. In this work realizing of hazards map of Dades basin was based on field investigation, satellites data, and processing of digital elevation model using GIS softwares. This mapping allows an overall appreciation of basin susceptibility at ground instability. This work is a first backgrounder and sensibilization of the landslides risk in study area

Morphological Evolution and Sedimentological Study of the Essaouira Bay and the Mouth of Oued Ksob, Essaouira, Morocco

The coastline of Essaouira is located on the Atlantic coast of Morocco. The Bay of this city is a large sandy system strongly marked by coastal and fluvial dynamics, which makes it a perfect example of sedimentology processes in a Bay area. using of satellite imagery allows us to determine the morphological evolution of the Essaouira Bay and the mouth of Oued Ksob. The results of the study show the evolution of the coastline of the Essaouira Bay with areas of erosion and others in accumulation. The analysis of satellite images allows us to distinguish three very different sectors: the first is north of the estuary of Oued Ksob, this area receives most of the flood contributions of Oued Ksob, which helps to maintain its morpho-sedimentary balance. The second sector, which is composed of the estuary and the mouth of the Oued Ksob, is characterized by a hydrodynamic both fluvial and maritime. The third sector is located south of the estuary of Oued Ksob, which is not affected by the effect of the presence of the obstacle on the island of Mogador. The sedimentological study is carried out in four different areas, which are: the dunes, the mouth of Oued Ksob, which has undergone numerous recorded positions since the late 19th century, the area south of the estuary, and the area north of the mouth. Several analyses were carried out namely: granulometry, morphoscopy, calcimetry, and X-ray diffraction, which confirmed that the origin of the studied sediments is both continental and marine

A qualitative assessment of desertification change in the Tarfaya basin (Morocco) using panchromatic data of Landsat ETM

The purpose of the present work is to assess desertification change in the Tarfaya basin (Morocco) based on quantifying sand dunes mass change at the corridor scale using two Panchromatic bands of Landsat ETM+ and OLI with 15 m of resolution covering the study area for ten years (2005–2016). In this work, the sand dunes quantification is qualitative and is based on automatic extraction and classification of sand dunes shape using co-occurence texture filters and Support Vector Machine (SVM) classifier. The statistical results show that the area covered by sand was increased during the last ten years, which reveal that desertification becomes more intense