Abdelghani El Harfi

University Ibn Zohr - Agadir · Geology

Amethysts from Boudi, Morocco, are characterized by double terminations and hourglassshaped color zoning. This study provides infor mation about the geology of the deposit, the mining of the material, and its internal and external features. Photos show the amethyst's strong color zoning. Analysis of the needle-shaped mineral inclusions identified t...

The discovery of Upper Miocene vertebrates at Tizi N'Tadderht in the Ouarzazate basin (Morocco) helps to fill a gap in our knowledge of Neogene faunas in North Africa. The new fauna includes an ostrich cf. Struthio sp, a turtle cf. Centrochelys sp., Crocodylus cf. nirloticus, and a relatively diverse fauna of large mammals. The mammal assemblage pr...

This paper describes a tectonostratigraphic model of the synrift evolution of the Early Jurassic High Atlas rift of Morocco. The model is constrained by mapping of a set of inverted extensional blocks, by facies analysis of carbonate platform and turbiditic to hemipelagic synrift deposits, and by high-resolution (n 3 100 ka) biostratigraphy of the...

Previous crustal models of the High Atlas suppose the existence of a mid-crustal detachment where all the surface thrusts merged and below which the lower crust was continuous. However, both seismic refraction data and gravity modeling detected a jump in crustal thickness between the High Atlas and the northern plains. Here we show that this rapid...

A re-interpretation of the deep structure of the High Atlas is presented through integration of geophysical and geological data, highlighting the architectural significance of the southern Tethys palaeomargin. Previous crustal models suggest the occurrence of a flat intra-crustal detachment at a depth of −20km, a zone where surface thrusts merge an...

Les Microcodium sont des structures énigmatiques de nature encore incertaine désignant des cristallisations de calcite limpide, en prismes ou pyramides allongés, groupés, soit en « épis de maïs », soit en lames encroûtantes plus étendues. Les prismes de calcite montrent des microstructures internes qui consistent en de très fins filaments (diamètre...

Les Microcodium sont des structures énigmatiques de nature encore incertaine désignant des cristallisations de calcite limpide, en prismes ou pyramides allongés, groupés, soit en « épis de maïs », soit en lames encroûtantes plus étendues. Les prismes de calcite montrent des microstructures internes qui consistent en de très fins filaments (diamètre...

Cenozoic continental sedimentary deposits of the Southern Atlas named "Imerhane Group" crop out (a) in the Ouarzazate foreland basin between the Precambrian basement of the Anti Atlas and the uplifted limestone dominated High Atlas, and (b) in the At Kandoula and At Seddrat nappes where Jurassic strata detached from the basement have been thrust so...

Tectonic and sedimentary study of the Tertiary continental infilling of the Ouarzazate foreland basin reveals two stages of erogenic uplift of the Central High Atlas Mountains. The first stage took place in the Late Eocene-Oligocene after the retreat of the sea at the end of the Mid Eocene. The second stage occurred in the Mid Pliocene in conjuncti...