Sedimentology and morphology of quaternary alluvial fans in Wadi Araba, Southwest Jordan

Abstract EN

The eastern rim of Wadi Araba in southwest Jordan displays distinct alluvial fans, which were developed since the time of formation of the Dead Sea Transform (DST), initiated in Mid Miocene times.

The DST fault system controlled the development of the alluvial fans and their stacking pattern.

Siliciclastic sediments were supplied from the east, and dispersed radially forming a stream-flow dominated alluvial fan system.

The continuous uplift of the eastern granitic basement and overlying Phanerozoic sedimentary succession, and the active in tramontane valleys, whose outlets at the mountain front were elevated continuously above the piedmont plains, resulted in deposition of alluvial fans that coalesced to produce a huge banana complex comprising several generations of overlapping and superimposed lobes consisting mostly of granitic gravels.

Eight lithofacies are identified, comprising three lithofacies associations: proximal fan; medial fan and distal fan.

These were deposited in environments ranging from proximal shallow stream and sheet floods, channelized non-cohesive debris flows, medial heterolithic deposits, distal muds and sabkha evaporates.