Growth and linkage of the East Tanka fault zone, Suez rift: structural style and syn-rift stratigraphic response

Abstract

Abstract: An integrated tectono-stratigraphic analysis of the East Tanka fault zone, Suez rift, indicates fault growth by linkage of initially isolated fault segments that is consistent with fault growth models based on displacement–length (D-L) scaling laws. During the initial 2.4 Ma of rifting, the East Tanka fault zone was composed of two en-echelon fault segments c. 1–1.5 km long, separated by a hanging-wall intrabasin high that controlled the geometry of depocentres filled with continental deposits. Alluvial fan conglomerates were fed through the region between the two fault segments, and form a discrete coarse-grained body, preserved in the immediate hanging wall of the fault zone. Subsequent stratigraphic patterns indicate that the two faults hard-linked to form a single fault zone c. 3.5 km long. Hard linkage of the segments resulted in migration of the zone of maximum displacement and subsidence into the zone of linkage. Uplift due to the migration of activity caused modification of drainage in the footwall of the fault zone that terminated the growth of the alluvial fan. This study demonstrates the need to integrate structural and stratigraphic data when attempting to reconstruct the temporal and spatial evolution of normal fault zones. Additionally, the fault dynamics illustrated have implications for tectono-stratigraphic models of rift basins, and syn-rift stratigraphic evolution.