ABSTRACT Detrital zircon U-Pb geochronology has been widely used to constrain the pre-Carboniferous geography of the European and, to a lesser extent, the Moroccan Variscides. The latter have been generally considered as part of a long-lasting passive margin that characterized northern Gondwana from Ordovician to Devonian time, and was subsequently involved in the late Paleozoic Variscan orogeny. We report detrital zircon ages for three Early to Late Ordovician samples from the Beni Mellala inlier in the northeastern part of the Western Moroccan Meseta in order to discuss the temporal evolution of the sources of sediments in this region. The detrital zircon spectra of these samples, characterized by two main populations with mean ages of 630–610 Ma and 2170–2060 Ma, are typical of Cambrian–Devonian rocks from the Moroccan Variscides and confirm their link to the West African craton. A minor Stenian–Tonian population (peak at ca. 970 Ma) suggests the influence of a distant and intermittent NE African source (Sahara metacraton), which was probably interrupted after Ordovician time. Our data support previous interpretations of the Moroccan Meseta (and the entire northern Moroccan Variscides) as part of the northern Gondwana passive margin. The main sources of these sediments would have been the West African craton in the western regions of the passive margin (Moroccan Meseta and central European Paleozoic massifs), and the Arabian-Nubian Shield and/or Sahara metacraton in the eastern areas (Libya, Egypt, Jordan, central and NW Iberian zones during Paleozoic time), where the 1.0 Ga detrital zircon population is persistent throughout the Ordovician–Devonian time span.

Paleozoic formations crop out extensively in Morocco, north of the West African craton. With regard to the Hercynian deformation, various structural domains can be distinguished in Morocco. The undeformed series of the southern flank of the Tindouf basin belong to the tabular cover of the Reguibate shield. Zemmour and Anti-Atlas are parts of a marginal belt, mildly deformed, around the West African craton. The Coastal Block, North-central, and Northeastern domains constitute the Moroccan Hercynian belt, which has been more or less strongly deformed between Late Devonian and Late Carboniferous times. In spite of these various states of deformation, these domains are not distinct terranes since there was a general continuity between them during Paleozoic time; they correspond to the same epicontinental shelf, itself related to the West Africa craton during early Paleozoic time. Later on, their Carboniferous sedimentary facies graded laterally from one domain to the other, and finally, no large-scale displacement occurred between them during or after their Hercynian deformation. On the other hand, three domains show sedimentological and structural differences with the rest of Morocco, which distinguish them from the areas connected with the Western Africa craton. The Western Sahara belt is a Mauritanide klippe thrusted eastward upon the craton. The Sehoul domain probably separated during Late Cambrian and Ordovician time from northern Morocco and it was accreted again to the rest of Morocco at the end of Ordovician time by a pre-Hercynian Taconic orogeny. The Internal Rif is an alpine allochthon that was located elsewhere during Paleozoic time, probably at the prolongation of northeastern Morocco. Therefore, Western Sahara, Sehoul, and Internal Rif are Paleozoic terranes.

U-Pb dating of detrital zircons separated from paragneiss of the Myrsini Crystalline Complex of eastern Crete yielded peaks in 207 Pb/ 206 Pb ages at 0.6, 0.8, 1.0, 2.0, and 2.5 Ga. A striking Mesoproterozoic age gap is present between 1.1 and 1.6 Ga. The new data are compatible with U-Pb zircon ages derived from surrounding crystalline complexes of the Cyclades, the Menderes Massif, Egypt, and the Levant. Possible provenances of the zircons of the eastern Mediterranean domains are the Sahara meta-craton, the Arabian-Nubian Shield, and the Kibaran belt of central Africa. Because the age spectra of the eastern Mediterranean crystalline complexes differ significantly from those of the Cadomian- and Avalonian-type terranes, they are regarded as a separate collection of peri-Gondwanan terranes referred to as Minoan terranes. In late Neoproterozoic to ?Cambrian times, the latter underwent Andean-type orogeny at the northern border of East Gondwana, close to Egypt and the Levant. There is no evidence that the Minoan terranes traveled for long distances in Phanerozoic times.