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The early Toarcian is characterized by the occurrence of widespread black shale deposits, recorded extensively across Europe and interpreted to be related to an Oceanic Anoxic Event. In order to investigate the source-rock potential of lower Toarcian deposits in Morocco, detailed sedimentary logging accompanied by outcrop spectral gamma-ray measurements were carried out on four sections representative of different palaeo-depositional settings in the Central High Atlas. Authigenic uranium enrichment is used as a proxy for oxygen-depleted depositional conditions, and may thus indicate potential organic-rich lithologies. Of the four measured sections, only one (the Amellago section, which represents the deepest marine setting) shows relative authigenic uranium enrichment. Complementary TOC analyses (with maximum values of 3.24%) over this interval confirm an associated enrichment trend in organic matter. The organic matter recovered from the outcrop samples is however highly oxidised, and thus the absolute value is not regarded as being a true record of the rocks' organic content. It is concluded from this study that early Toarcian potential source rocks were deposited within restricted sub-basins in the Central High Atlas. It is therefore possible that organic-rich deposits of Toarcian age are present in similar palaeogeographic settings in other areas of Morocco. This increases the exploration potential of Moroccan basins in which Jurassic deposits are potential source rocks. [ABSTRACT FROM AUTHOR]

The article presents the author's opinion on the Numidian Flysch provenance. He informs that Oligocene-Miocene Numidian Flysch is a suite of deep-marine sandstones with quartz-rich petrofacies, which crops out within the Alpine thrust belt of North Africa and extended upto Spain and Italy. He states that the detrital zircons provides a valuable tool for the identification of sediment provenance. He states a study of reveals that Cambrian and Precambrian ages are common in Flysch provenance.

Zebrafish gastrulation and particularly epiboly that involves coordinated movements of several cell layers is a dynamic process for which regulators remain to be identified. We show here that Flotillin 1 and 2, ubiquitous and highly conserved proteins, are required for epiboly. Flotillins knockdown compromised embryo survival, strongly delayed epiboly and impaired deep cell radial intercalation and directed collective migration without affecting enveloping layer cell movement. At the molecular level, we identified that Flotillins are required for the formation of E-cadherin-mediated cell-cell junctions. These results provide the first in vivo evidence that Flotillins regulate E-cadherin-mediated cell-cell junctions to allow epiboly progression., (© 2017 Société Française des Microscopies and Société de Biologie Cellulaire de France. Published by John Wiley & Sons Ltd.)