Inversion of synrift normal faults in the High Atlas Mountains, Morocco
نویسنده
چکیده
Structural inversion related to intracontinental rifting occurs when extensional rift faults reverse their sense of motion during subsequent episodes of compressional tectonics. Features generated by extension, such as half grabens, are uplifted to form positive anticlinal structures. Mountain belts resulting from the convergence of continent-continent or continent-oceanic plates usually form along the margins of such plates. In contrast, intracontinental mountain belts such as the Atlas Mountains of North Africa, the Palmyrides of Syria and the Cordillera Oriental/Merida of Colombia and Venezuela often form hundreds of kilometers from nearby plate boundaries. Stresses generated by plate convergence are transmitted to the interior of continental plates where the strain is accommodated along preexisting zones of weakness in the crust, such as rifts, aulacogens, and sutures, resulting in intracontinental mountain belts. The High Atlas Mountains of Morocco are an intracontintental mountain belt formed by the inversion of a preexisting Mesozoic rift system (Figure 1). The Atlas Mountains of North Africa extend for approximately 2000 km from the Atlantic margin of Morocco to the Mediterranean coast of Tunisia, and were formed during the Alpine orogeny in the MioceneOligocene.
منابع مشابه
Piecewise delamination of Moroccan lithosphere from beneath the Atlas Mountains
The elevation of the intracontinental Atlas Mountains of Morocco and surrounding regions requires a mantle component of buoyancy, and there is consensus that this buoyancy results from an abnormally thin lithosphere. Lithospheric delamination under the Atlas Mountains and thermal erosion caused by upwelling mantle have each been suggested as thinning mechanisms. We use seismic tomography to ima...
متن کاملHot upwelling conduit beneath the Atlas Mountains, Morocco
The Atlas Mountains of Morocco display high topography, no deep crustal root, and regions of localized Cenozoic alkaline volcanism. Previous seismic imaging and geophysical studies have implied a hot mantle upwelling as the source of the volcanism and high elevation. However, the existence, shape, and physical properties of an associated mantle anomaly are debated. Here we use seismic waveform ...
متن کاملControls on modern tributary-junction alluvial fan occurrence and morphology: High Atlas Mountains, Morocco
متن کامل
A new species of Gymnocnemia Schneider, 1845 from Morocco with additional diagnostic data for the genus (Neuroptera, Myrmeleontidae).
Gymnnocnemia editaerevayae nov. sp. is described from the High Atlas Mountains in Morocco and compared to Gymnocneinia variegata Schneider, 1845. Descriptions of male genitalia and male and female terminalia of G. variegata are provided. Both species are illustrated.
متن کاملPositive inversion of extensional footwalls in the southern Serra do Espinhaço, Brazil--insights from sandbox laboratory experiments.
Analogue experiments were carried out to get insights into the processes governing positive inversion during the foreland propagating thrust tectonics in the southern Serra do Espinhaço, a Brasiliano/Panafrican foldthrust belt in southeast Brazil. In particular, model listric half-grabens were inverted by applying contractional displacement to the footwall blocks. We investigated two different ...
متن کامل