Succession of depositional environments in the Neogene basin at Aliveri, Evia (Greece)

Abstract The Neogene lignite-bearing sequence in the southern part of the Aliveri-Kymi basin was studied with regard to sedimentology, palynology and coal petrology in order to establish the type and succession of environments involved and to compare them with modern analogues. Initial sediments of the Prinias Group were deposited in a wide shallow depression by means of a low competent drainage system which formed sandy alluvial fans, interfan areas and ephemeral lakes as well as sand flats and vegetated mudflats in lateral sequences from the basin margins to a central perennial lake. Succeeding sediments of the Prinias Group were formed under the influence of the rising lake level in algal-marsh, various peat-forming and open-lake environments. Sediments of the Koustoumalou Group were deposited by a highly competent surficial drainage system in alluvial fan to braided and meandering fluvial environments. This drainage system followed the south-north trending axis of an asymmetrical graben while debris-flows moved in from the steep flanks to the east.