Agoudal (High Atlas Mountains): Confirmation and First Studies of a Remnant of a Post Mid-Jurassic Impact Structure in Morocco. H

77th Annual Meteoritical Society Meeting (2014) 5318.pdf

AGOUDAL (HIGH ATLAS MOUNTAINS): CONFIRMATION AND FIRST STUDIES OF A REMNANT OF A POST MID-JURASSIC IMPACT STRUCTURE IN MOROCCO. H. EL Kerni1, H. Chennaoui Aoudjehane1, M. Aboulahris1, W. U. Reimold2, C. Koeberl3, P. Rochette4, Y. Quesnel4, M. Uehara4, A. Hutzler4, D. Bourles4, S. Bouley5, M. Aoudjehane6. 1Hassan II University Casablanca, Faculty of Sciences Ain Chock, GAIA Laboratory, BP 5366 Maarif 20000 Casablanca, Morocco. Email: [email protected]; 2Museum für Naturkunde Berlin and Humboldt University Berlin, Germany; 3Museum of Natural His- tory Vienna and University of Vienna, Austria, 4CEREGE, CNRS Aix-Marseille University , BP80 13545 Aix en Provence, Cedex 4, France.Aix en Provence cedex 4, France; 5 IDES- Inter- actions et Dynamique des Environnements de Surface Université Paris Sud, France. 6 302 Boulevard Panoramique, 20150 Casa- blanca, Morocco.

Introduction: A large outcrop of shatter cones [1] was found in spring 2013 by a Russian team searching for the Agoudal meteorite [2,3]. We carried out two field missions to the site in early October 2013 and in early May 2014 to investigate the shatter cone provenance, and to search for any possible relationship be- tween them and the Agoudal iron meteorite fall [1]. Besides first geological reconnaissance in the area, geophysical research in- cluding paleomagnetic measurements was conducted [4]. The Agoudal meteorite is the most recently approved iron meteorite from Morocco [2]. It has been classified as an IIAB iron. The total mass was estimated at more than one tone and the extent of the estimated strewn field is about 10x1 km. The village of Agoudal is located in the High Atlas Moun- tains in Morocco, about 20 km southeast of the town of Imilchil, and about 25 km southeast of lakes Isli and Tislit. While these lakes have been repeatedly referred as impact locations, pertinent literature [5,6] refutes this possibility. Our group has also failed to locate any indication for impact at these locations. The shatter cones were found at a limited area of some 500x500 m in Binelouidane Marly Limestone Formation deposited during the Bajocian period [6,7]. The site is located at the southeastern end of the Agoudal meteorite strewn field. During the second field mission structural features in the area around the shatter cone site were mapped. In general outcrop conditions are very poor and stratigraphic correlation is difficult. The team hopes to obtain confirmation of bedding attitudes from anisotropy of magnetic susceptibility and paleomagnetic (13 sites inside and outside the shatter-cones area have been cored) data. Generally, it can be stated at this time already that most structures such as folding, faulting, and fracturing correlate with pre-mid Jurassic alpine deformation. References: [1] Sadilenko D.A. et al. (2013) 76th Annual Meteoritical Society Meeting, abstract 5215. [2] Chennaoui Aoudjehane H. et al., (2013), 76th Meteoritical Society meeting, abstract 5025. [3] Garvie L. et al. (2013), Meteoritics & Planet. Sci. 47. [4] Rochette P., et al., 77th Meteoritical Society meeting, abstract 5211. [5] Ibouh et al. (2014), C. R. Geoscience, http://dx.doi.org/10.1016/j.crte.2014.03.005 [6] Michard A. et al. (2011) Terra Nova, 23, 314-323. [7] Ellero A. et al. (2012) “Tec- tonics-Recent Advances”, ISBN 8-953-51-0675-3.