Jordan is situated on the northwestern side of the Arabian Plate, along the eastern flank of the ancient Tethys Ocean on the western side of the Dead Sea Transform. The country hosts huge phosphate deposits. The deposits at Eshidiya are comprised of overburden, four phosphate beds (A0, Al, A2 and A3), a coquina/marl waste bed, and two silicified phosphate chert interwaste beds.
The Eshidiya phosphate deposits in central Jordan lie within the Upper Cretaceous limestone plateau. They comprise about 125 sq. km and are estimated to be 65 million years old (Upper Cretaceous). The deposits are sedimentary in nature and are thought to have been formed in the following sequence:
(i) upwelling of cold, phosphate-rich seawater into warm shallow waters,
(ii) growth of algae, plants, fish, and mammals due to the rich nutrients,
(iii) phosphatization of calcareous, siliceous and clay sediments on the shallow sea floor, along with deposition of phosphate-rich teeth and bones from animals,
(iv) reworking of the phosphate sediments by current or wave action and finally,
(v) after the seawater receded, weathering of the phosphate sediments, with rains that leached the softer limestone and left behind the quartz and less soluble phosphates.
The phosphorites of Jordan are present within Al-Hisa Phosphorite Formation (AHP). In general, the AHP consists of phosphorites, bedded chert, limestones, oyster buildups, organic-rich marl (oil shale ........
