A regional stratigraphic correlation for the upper Campanian phosphorites and associated rocks in Egypt and Jordan

Abstract

Facies analyses and a sequence stratigraphical framework with regional correlation of the upper Campanian phosphate province are presented, based on three main sections located in Egypt (Gebel Duwi and Abu Tartur sections) and north Jordan (Umm Qais section). Fifteen facies types were grouped into: phosphate (FT1–5), carbonate (FT6–11) and siliciclastic (FT12–15) facies associations. The main component of phosphate rocks is pellets in situ and common reworked biogenic debris, especially in the upper phosphate beds (e.g. fish teeth and bones), which along with abundant Thalassinoides burrows suggests that the skeletal material was the main source for phosphates in Egypt; in contrast the common authigenic phosphatic grains (pristine) in Jordan reflect an upwelling regime. Based on age assignment as well as stratigraphical position, the phosphorite beds show great similarity that may suggests a similar origin and proximity during the period of deposition of the Duwi Formation of the Red Sea coast of Egypt and its equivalent, the Al-Hisa Phosphorite Formation in Jordan, which represents an early transgressive system tract of a depositional sequence. On the Abu Tartur plateau, the presence of sandy pyritic phosphatic grainstone (FT1) and glauconitic quartz arenite (FT12) in the middle part of the studied section, along with the absence of chert facies (FT14), reflects a more shallow marine depositional environment with increased fluvial sediment supply compared to those along the Red Sea coast and north Jordan.