THE ORIGINS OF MARINE CONGLOMERATES IN THE PINDUS FORELAND BASIN, GREECE

Conglomeratic sediments in the Pindus foreland basin of western Greece record major sedimentary events and give important clues to aid the interpretation of the basin dynamics. The principal source of detritus lay to the southeast and east, in the adjacent Pindus thrust belt, although minor amounts of sediment were derived from a carbonate platform in the west. The topography of the basin floor was controlled by movement on thrusts propagating westward in advance of the mountain front. Locally, thrusts broke up-section to produce limestone-cored thrust culminations emergent above the basin-floor sediments. The topography over these structures locally formed intrabasinal sediment sources. Three major process-related classes of conglomerate are recognised in the basin: (a) clast-supported, polymict conglomerates interpreted as high-density turbidity current deposits with a similar source to widespread sandy turbidite deposits; (b) muddy, matrix-supported, polymict conglomerates representing resedimented material from the mountain front; (c) oligomict, clast-supported conglomerates derived locally from topographic highs within the basin. The debris flows and turbidites were triggered on the mountain front but followed different flow paths into the basin. The features described here are thought to be characteristic of gravity flow-dominated sedimentation in an active foreland basin. © 1990.