Nuevas icnitas terópodas y prosaurópodas en Issil-n-Aït Arbi (Jurásico Inferior, Alto Atlas Central, Marruecos)

El conjunto de afloramientos de 1AAR presenta huellas de dinosaurios bípedos y cuadrúpedos. Las huellas bípedas se han asociado a icnitas terópodas y prosaurópodas, mientras que las segundas se asocian a icnitas prosaurópodas. Cabe la posibilidad de que parte de las icnitas cuadrupedas sean saurópodas, pero la mala conservación y las condiciones de los afloramientos no permiten hacer observaciones directas ni apropiadas sobre ellas. En este trabajo se describen los caracteres determinativos y la posible asignación de las icnitas.Aunque no es la primera vez que se mencionan huellas prosaurópodas en AAR, las de estos afloramientos son morfológicamente diferentes debido probablemente al comportamiento del barro durante la formación de la pisadaThe 1AAR group of outcrops show traces of bipedal and quadrupedal dinosaurs. The bipedal ichnites have been associated with theropod and prosauropod footprints, while the quadrupedal are associated with prosauropod footprints. It is possible that some of the quadrupedal traces were sauropod footprints, but the poor preservation and the outcrop conditions do not allow us direct and appropriate observations of them. Diagnostic characters and the possible attribution of the footprints are described in this paper. Although it is not the first time that prosauropod traces are signaled from the AAR, the footprints of the present outcrops result morphologically different, probably due to reaction of mud during the formation of the ichnit

Paleoichnological explorations in the Iouaridène syncline (Hight Atlas. Morocco). 2: East part

In 2007, the dinosaur footprints research group of the Universities of Rabat and La Rioja began the mapping of the Iouaridène ichnological sites. The initial problems were the footprints number - several thousands for some scientits- the ichnotaxonomy, and their geographical and geological distribution. Our first results (west Iouaridène area) were published in 2008. In addition to two ichnotaxons defined here, we have studied: gigantic theropod and ornithopod footprints; semipantigrade theropod ichnites and the largest world theropod trackway are new contributions to Iouaridène dinosaur footprints knowledge. In this work, are demostrated the following questions: i) the maximun number of footprints in the Iouaridène sincline is less than 2000; ii) in the east area there is minor density of sites and the number of footprints that in the west part; iii) the greatest number of semiplantigrade theropod ichnites; iv) the fosiliferous levels reduction from 20 to one. Probably, the four properties geographically related - stratigraphic, number, density (sites and footprints) and the diversity of semiplantigrade ichnites - are other singenetic relation

New Domerien dinosaur footprint sites fromlbaqalliwn (Ai't Bou Guemez Hight Central Atlas. Moroco)

During the 2009's summer courses (universities Rabat-La Rioja) 6 new paleoichnological sites are found in the Bou Guemez river. The previously know Ibaqalliwn-Talsnant sites are located in the close west. All new, and Ibaqualliwn-Talsnant fossil traces, are print over the upper levels of marine limestones from Arganane Formation (Domerian). The likewise Domerian lowermost part continental sediments of the superposed Azilal Formation is placed to 5 m above the ichnites. The Utological composition, invertebrate fossil content, and number ofichnological levels is similar in the AssifAit-n-Bou Cuemez-Assif-n-Rbat zone. In spite ofthe Quaternary aluvial sediments cover, the geological properties are enough to define exactly the same stratigraphic position of the sites. The Arganane Formation dissapear to east part and the new sites are the east end ofthe Bou Guemez dinosaur footprints outcrops. It is important show the sauropod supremacy in the Bou Guemez zon

The 34IGR dinosaur palaeoichnological site. Iouaridène, High Central Atlas. Morocco

En este artículo se estudia un nuevo yacimiento icnológico (34IGR) del sinclinal de Iouaridène, citado previamente por otros autores, pero no descrito. Las icnitas se caracterizan por su irregularidad, heterogeneidad y variación de tamaño. Los caracteres biomórficos y morfométricos tan variables son la respuesta, mostrada en el conjunto del sinclinal, a la diversidad biológica, morfológica y de estructuras inducidas por las propiedades físicas del barro. Este afloramiento es también la expresión de la variación de la cuenca, porque en este sector solo hay una capa con icnitas, frente a los yacimientos del oeste en los que hay superpuestas un número aún no determinado de capas fosilíferasIn this article is studied a new ichnological site (34IGR) of the Synclinal of Iouaridène already mentioned by the authors though still not described. The footprints are characterized by the ichnological heterogeneity and irregularity of his forms and dimensions. Both biomorphic and morphometricv characters answer to the variability showed in the ensemble of sinclinal sites relative to the biological diversity and to the morphology and structural response induced on the footprints by the physical characteristics of the mud. This site is also an expression of the evolution of the basin since he is in a sector that alone has one ichnological bed, against the deposits of the western part in which has been detected the overlapping of a number, still not assessed, of beds and levels with footprint

Anomalous content of semiplantigrade theropod footprints in the Oumzawrou (36IGR) outcrop of the Moroccan Atlas

Se describe por primera vez un yacimiento con huellas de dinosaurio (Oumzawrou o 36IGR), que era conocido desde hace cuarenta años.Es el segundo en cuanto al número de huellas del conjunto de 43 yacimientos del sinclinal de Iouaridène (IGR) . En 36IGR concurren varias particularidades en relación con los demás de IGR que lo hacen destacable: a) las icnitas están en un solo nivel al contrario de lo que ocurre en el resto de yacimientos estudiados del sinclinal; b) el número de icnitas y rastrilladas semiplantígradas es relativamente muy grande; c) no hay rastrilladas con dirección E-O. La concentración y la cantidad de de huellas semiplantígradas es un hecho excepcional tanto en IGR como entre los yacimientos similares conocidos del resto del mundo. Dadas la condiciones estratigráficas, icnológicas y paleoambientales del yacimiento se postula que una relación debe condicionar la coexistencia de icnotipos y la conducta de los dinosauriosWe describe for the first time a dinosaur tracksite (Oumzawrou or 36IGR) which was known for forty years. It is the second in the number of prints of all 43 sites discovered in the Iouaridène syncline (IGR) In 36IGR concur several particularities that make it remarkable, in relation to others of IGR: a) the footprints are only on a single level, as opposite to the other tracksites analysed in the syncline; b) the number of semiplantigrade footprints and trackways is relatively very large; c) there are no trackways with E-W direction. The concentration and number of semiplantigrade footprins is an exceptional fact both in IGR and in similar outcrops in the world. According to the stratigraphic, ichnologic and palaeoenvironmental conditions of the tracksite is postulated that a relation must restrict the coexistence of ichnotypes and the behaviour of dinosaur