In the vicinity of Taourirt dykes and sills, up to three metres thick, and a number of breccia pipes comprise rocks which were originally called aiounite and mestigmerite (see Jérémine, 1948 and Cherotzky, 1967) the former being described as ferromagnesian-rich rocks of augite, biotite and opaqu
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Alkaline rocks occur in two principal zones in Morocco: a northern zone of east-northeast - west-southwest trend which extends across the Middle Atlas and a parallel, southern, less extensive one which lies south of the High Atlas mountains. Both zones comprise a number of provinces or centres but, apart from the Azrou area, they are characterised by numerous widely scattered volcanic edifices, dykes and plugs. There is no overall review of the petrology of these rocks but there are general accounts giving the petrography of rocks of individual centres notably by Termier (1936), Jérémine (1955) and Cherotzky (1970). The broad range of highly alkaline suites represented, including basanitic, nephelinitic, phonolitic and comenditic rocks, would suggest the desirability of a full study of the province. Numerous unpublished theses are cited in the more recent publications but these have not been consulted.
The Tamazert complex of carbonatite, pyroxenite and nepheline syenite is located in the High Atlas, having been emplaced in a thrust plane within the core of a large anticlinal structure. Such a tectonic setting is most unusual for a carbonatite complex; it is also noteworthy for the abundance of dykes, of a broad range of compositions, and pegmatite minerals.
Over this very large area isolated occurrences of alkaline rocks take the form of lava flows and small volcanoes and craters; this is referred to as the Rekkame Province by Rachdi et al. (1997).
Over this large region there are extensive areas of basaltic flows, notably southeast of Azrou, with numerous volcanic centres including maars and particularly abundant scoria cones (Gentil, 1916; Harmand and Cantagrel, 1984).
In an area extending from approximately 20 km northwest of Oulmes to about 70 km to the southeast there are occurrences of recent volcanic rocks of widely differing extent which have emanated from about 20 volcanic centres.
A prominant hill extending over 4x2 km on the south bank of the Oued Moulouya comprises a series of lava flows that overlie Triassic and Jurassic sedimentary rocks and basalts and Pliocene conglomerates (Jérémine, 1955).
This locality, an account of the field relationships of which has not been found, is listed by Jérémine (1955, p. 68) as an ankaratrite consisting of phenocrysts of olivine in a matrix of augite, biotite, aegirine-augite, hornblende, nepheline and analcime.
Tamazert is an elongate complex 18 km in length and up to 6 km wide which has been emplaced along a major thrust plane in the core of a large anticline on the northern margin of the High Atlas, the intrusion varying between 1800 and 2970 m above sea level.
Overlying Precambrian schists, granites and volcanic rocks in the vicinity of Zaker are phonolitic tuffs and lavas which for the most part form small (<1 km diameter) areas with one larger, irregular occurrence extending east-west for 11 km. The thickness is generally less than 100 m.
Siroua is a strato volcano 25 km in diameter set directly on Precambrian rocks, principally schists and granites. It is located on a major fault zone which separates the Atlas from the Anti-Atlas tectonic zones.
To the north of Oujda there are extensive areas of basaltic rocks and to the south similar rocks occur but of more restricted extent. Amongst the basaltic rocks are analcime- and nepheline-bearing varieties.