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Abstract: The Betic–Rif orogen, at the western end of the Mediterranean, is a key region to improve our knowledge on the Africa–Eurasia convergence. The Temsamane units, in spite of their external position in the Rif (northern Morocco), underwent medium-pressure low-temperature (MP–LT) conditions (ca. 7–9 kbar; 330–430 °C). We propose a new tectonic and metamorphic evolution scenario for the Rif (southern) branch of the orogen on the basis of first 40Ar/39Ar dating on petrologically and structurally characterized white micas. Three groups of 40Ar/39Ar ages are observed: (1) Chattian or older Si-rich (highest-pressure) mica relics, (2) 15–12.5 Ma corresponding to the micas defining the foliation and (3) Messinian or younger late micas and alteration. We propose that the MP–LT metamorphic event in the External Rif is Oligocene in age, highlighting a subduction event during this period which could be almost contemporaneous with the burial of HP–LT units from the internal Rif (Alboran Domain). The exhumation of these units characterized by an intense E–W stretching and by top-to-the-west shear senses, is Middle to Late Miocene in age. We propose a correlation of tectonic and metamorphic events at the Betic–Rif arc scale. We argue that the exhumation of the external units of the Rif (1) is younger than that of the Alboran Domain (internal) unit of the Rif, and mirrors a different tectonic setting, but (2) strongly resembles to that documented in the lower Alboran Domain units of the Betics. We show that a regional E–W extension is recorded on both sides of the Betic–Rif arc during the Middle Miocene. This extension probably reflects back-arc deformation of an eastward dipping subduction that retreated westward during the Middle to Late Miocene in the Western Mediterranean. [Copyright &y& Elsevier]

We characterized the full-length genomes of nine hepatitis C virus genotype 3 (HCV-3) isolates: QC7, QC8, QC9, QC10, QC34, QC88, NE145, NE274 and 811. To the best of our knowledge, NE274 and NE145 were the first full-length genomes for confirming the provisionally assigned subtypes 3d and 3e, respectively, whereas 811 represented the first HCV-3 isolate that had its extreme 3' UTR terminus sequenced. Based on these full-length genomes, together with 42 references representing eight assigned subtypes and an unclassified variant of HCV-3, and 10 sequences of six other genotypes, a timescaled phylogenetic tree was reconstructed after an evolutionary analysis using a coalescent Bayesian procedure. The results indicated that subtypes 3a, 3d and 3e formed a subset with a common ancestor dated to ~202.89 [95% highest posterior density (HPD): 160.11, 264.6] years ago. The analysis of all of the HCV-3 sequences as a single lineage resulted in the dating of the divergence time to ~457.81 (95% HPD: 350.62, 587.53) years ago, whereas the common ancestor of all of the seven HCV genotypes dated to ~780.86 (95% HPD: 592.15, 1021.34) years ago. As subtype 3h and the unclassified variant were relatives, and represented the oldest HCV-3 lineages with origins in Africa and the Middle East, these findings may indicate the ancestral origin of HCV-3 in Africa. We speculate that the ancestral HCV-3 strains may have been brought to South Asia from Africa by land and/or across the sea to result in its indigenous circulation in that region. The spread was estimated to have occurred in the era after Vasco da Gama had completed his expeditions by sailing along the eastern coast of Africa to India. However, before this era, Arabians had practised slave trading from Africa to the Middle East and South Asia for centuries, which may have mediated the earliest spread of HCV-3., (© 2014 The Authors.)