GEOMORPHOLOGY OF THE LOW FOLDED ZONE

Abstract

The geomorphology of the Iraqi Low Folded Zone (LFZ) is reviewed in the present article. Narrow, elongated and elevated mountainous chains with highly rugged terrain, and the wide gently sloping flat plains with local slight undulation represent the main topographic features of the LFZ. These features reflect the main geological structural relief's and the action of different geomorphologic processes. Moreover, the surface of the study area is dissected by complicated drainage patterns with variable density; they drain the study area towards the main streams and rivers, and then ultimately toward the Tigris River. The water flow erosion is dominant and active processes, beside less affectively wind erosion. A simplified geomorphologic map of the LFZ is compiled. This elucidates the spatial distribution of the main geomorphologic units and related morphologic features. The geomorphologic units are classified genetically into seven classes, which include different landforms. The recognized genetic units are; Structural-Denudational, Denudational, Fluvial, Solution, Evaporation, Aeolian, and of Man-made origins. Each of these units include different lithomorphologic landforms, which were developed as a result of weathering, erosion and deposition processes, in conjunction with tectonic, structural, lithologic, and climatic factors.The present study revealed that the geomorphologic evolution of the LFZ was greatly influenced by the last phase of intensive orogenic movement that took place during Late Miocene – Pliocene, and continued during Quaternary Period with less intensity. During the Quaternary Period, the climate became leading factor in controlling the majority of geomorphologic processes, particularly the fluvial. The Quaternary long-term climatic changes are deduced by well developed river terrace stages along the Tigris River valley, in particular.