THE BURIED AFIQ CANYON (EASTERN MEDITERRANEAN, ISRAEL) - A CASE-STUDY OF A TERTIARY SUBMARINE-CANYON EXPOSED IN LATE MESSINIAN TIMES

The Afiq submarine canyon was one of a series of canyons initially incised in a drowned shelf edge and slope of the eastern Mediterranean margins in early Oligocene times (P19 zone). During most of the Early Miocene submarine erosion or non-deposition prevailed. This was followed by deposition of pelagic marls and debris flows in early Middle Miocene (NX) times. Large-scale sliding in late Middle Miocene times (N14) resulted in the collapse of the slope, the removal of most of the middle Miocene sequence and the formation of a box-shaped scar. Back-cutting incision ultimately resulted in the incision of the shelf in Late Miocene times. A sea-level fall ranging between 50 and 800 m below the canyon's rim resulted in the deposition of the Messinian Lower Evaporites (Mavqiim Formation) within the canyon. A subsequent rise of a similar extent led to the deposition of the Upper Evaporites (Be'eri Gypsum) which are found on the canyon's southern shoulder. The final Messinian sea-level drop, below the canyon's floor resulted in a subaerial environment in the canyon, the erosion of the upper evaporites and the subsequent deposition of fluvial and brackish sediments (Afiq Formation). The latter correspond to the Lago-Mare sediments known throughout the Mediterranean. The rapidly rising sea level during the Pliocene along with the high rate of Nilotic elastic sedimentation resulted in the final burial of the Afiq Canyon, and a pronounced seaward progradation (20-30 km) of the shelf edge.