Quaternary Fluctuations and the Issue of Limited Pre-Late Pleistocene Fluvial Terraces on the Gharyan Plateau

Abstract

 In this study, the morphomorphic features of the quadruple oscillations in the Gharyan plateau were identified, after providing a brief idea of the most important geomorphological concepts of this time. Through the researcher's field survey, the limitations of the Pleistocene rivers terraces in the plateau were confirmed, especially the terraces of the Villafranchian (Paleoquaternary) period, which can be described as rare. Two ancient sediments were identified, on which field morphometric tests were performed for the standard study of gravel. It was found that one of them is a Al-Mallawi terraces sediment (middle Paleoquaternary), and the second sediment is a formation of an accumulating of slopes Deposits and not a terrace deposits. Therefore, the reasons for the limited availability of ancient terraces were investigated, and thus the study concluded that the oldest Quaternary river terrace identified on the plateau is the Middle Villafranchian Terrac, However, identifying older terraces, especially those preceding the Sultani Terrace, proved challenging due to their scarcity during this period. It was found that the oldest terraces (Villafranchian   Lower), which consisted of more than four terraces deposits, have become extinct at least until the present date.