Mass transport in Eocene pelagic chalk on the northwestern edge of the Arabian platform, Shefela area, Israel

ABSTRACT Glides, rotational slumps, debris‐ and mud‐flows occur in the Eocene pelagic chalk of the Shefela region, Israel. The pelagic lithofacies are present from the beginning of the Eocene, but mass transport is initiated only in the latest early Eocene and the early middle Eocene. Slight steepening of the palaeoslope, coupled with increased sedimentation rate and early diagenetic changes lowering inherent strength, led to gravity‐induced mass transport in the poorly consolidated pelagic sediments. Instability of the sediment pile was enhanced by underconsolidation and development of spacious packing associated with a relatively high rate of deposition and low initial strength due to high content of siliceous micro‐biota. The palaeogeographic position indicated by the mass‐transport features is the steepened, distal part of the ramp‐like continental margin of the Arabian Platform. Distal steepening of the ramp as part of regional downwarping is coincident with reactivation of Syrian Arc folding, reflecting northward convergence of the Arabian Plate during the Eocene.