Source: Pascal Brackman
The oldest part of the island of Lemnos consists of sedimentary deposits with ages ranging from middle Eocene (Lutetian) to early Miocene. Sandstone petrography indicates that the detritus is mainly composed by clasts of low-to-medium-grade metamorphic and sedimentary rocks, deriving from Rhodope Massif and Circum-Rhodope belt. During the late Oligocene and early Miocene, the sedimentary sequence was gently folded, eroded, and then covered by mainly continental sediments. Relatively intense magmatism started in early Miocene with pyroclastic flows followed by the emplacement of sills, lava flows and domes; three volcanic units, as well as a quartz-monzonite of limited extent (Fakos intrusion), cover much of the southwestern part of the island. K/Ar radiometric ages indicate that these rocks formed between 22 and 18 Ma. They have an orogenic affinity and relatively evolved compositions, with high-K dacites dominating over high-K andesites, latites and trachytes. The Limnos igneous rocks represent the first products in the North Aegean area, where the volcanic activity ceased in the middle Miocene. The Eocene to Miocene sedimentary succession exposed on the Island of Limnos reflects the geodynamic relations between the Serbo-Macedonian-Rhodope Massif, and the closure of Pindo (Subpelagonian) oceanic crust subducted at least from the Late Cretaceous under the European margin represented by the amalgamated units belonging to Rhodope-Vardar-Pelagonian zones.
Source: F.Innocenti et al.
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