Climatic Changes and the Evolution of Landforms in the Eastern Province of Saudi Arabia
The landforms in the Eastern Province of Saudi Arabia are features of a relict topography developed during late Pliocene, Pleistocene, and Holocene time under a variety of climates. The forms described in this report occur in the Dammam Dome, a gentle structural topographic rise composed of Eocene limestones, and in the Shedgum Area, a plateau underlain by late Miocene or Pliocene calcareous rocks. In the wetter climatic stages, stream erosion was the principal degradational process, whereas in the dryer stages pedimentation and related processes dominated. Landform development was also influenced by the structure and composition of the bedrock and by tectonic and possibly eustatic movements. During the late Pliocene and Pleistocene, a calcareous duricrust developed progressively on the topography, and in the late Pleistocene or mid-Holocene this crust was deeply weathered. More recently, desertic gradational processes have prevailed.