Upper Cretaceous tidal-flat sediments of the Abu Tartur region, Western Desert of Egypt, contain a variety of soft-
sediment deformation structures (SSDSs) in the Mut Member of the Quseir Formation and the overlying Duwi
Formation. Here, we document recognition of a set of SSDSs characterized by complex morphology and large
size. The SSDS include: 1) water-escape structures, 2) minor recumbent, chevron, and slump folds, 3) syn-
sedimentary minor faults, 4) neptunian dykes, 5) regular ball-and-pillow structures, flattened pseudo-nodules,
and load casts, 6) syn-sedimentary undulations, 7) fractures and joints, 8) sand injectites, and 9) autoclastic
breccia and brecciated siderite clasts. The dimensions of the SSDSs range from a few centimeters to several
decimeters. Both extensional and contractional forces appear to have been involved in development of these
structures. A detailed analysis of facies relationships, combined with consistent orientations of SSDSs and the
regional tectonics of the target area suggests earthquakes as the triggering mechanism for sediment deformation and large-scale mass failure. The deformed strata are consistent with most of the well-known criteria of typical seismites. Thus, syn-sedimentary liquefaction was identified as the primary driving force in most of the observed deformation horizons for these Upper Cretaceous SSDSs in the Abu Tartur area.
Research Abstract
Research Date
Research Department
Research Journal
Journal of African Earth Sciences
Research Member
Research Publisher
Elsevier
Research Vol
187
Research Website
https://www.sciencedirect.com/science/article/pii/S1464343X22000048?dgcid=author
Research Year
2022
Research Pages
104452