Landforms Evolution of Wadi Qudaid Area, West Central Arabian Shield, Saudi Arabia: An Example of the Role of the Geological Factors in the Urban Extensions

• 作者: Abdullah R. Sonbul Ali A. Mesaed Mohammed A. M. Alghamdi
• 来源期刊: 地质学期刊(英文)
• 学科: 地球科学
• 关键词: Wadi Qudaid Geomorphology of Saudi Arabia Landforms Evolution Erosion Cycle Urban Extensions
• 年，卷（期）: 2020,（6）
• 页码范围: 612-640
• 页数: 29页
• 分类号: P59

摘要

Wadi Qudaid is located in the west central part of Saudi Arabia. It about 135</span><span style="font-size:10pt;font-family:""> </span><span style="font-size:10pt;font-family:""><span style="font-family:Verdana;font-size:12px;">km to the northeast of Jeddah city along Al Haramein highway and it represents the upstream of the very large alluvial plain along the Red Sea coast. It runs in NE direction parallel to many wadis of the west central part of Saudi Arabia </span><i><span style="font-family:Verdana;font-size:12px;">i.e.</span></i><span style="font-family:Verdana;font-size:12px;"> Wadi Fatima, wadi Sitarah. The wadi floor is filled by Quaternary deposits which represent good groundwater aquifer. Geologically, the present-day residual landforms of Wadi Qudaid are composed mainly of Precambrian Arabia shield rocks overlained by Tertiary sedimentary rocks and finally harrat (Tertiary volcanic). The Precambrian rocks are represented by 1) a lower layered basic and intermediate volcanic and the intercalated volcaniclastics. This unit is correlatable with Samran Group, 2) an upper layered acidic volcanic and the intercalated acidic volcaniclastics. The Arabian shield rocks are intensively folded and dragged along the major NE faults. They are directly overlain by Tertiary basic volcanic (harrat) and the related volcanoclastic red beds). The main geomorphologic elements of the </span><span style="font-family:Verdana;font-size:12px;">study area include plateau, scarps, and the wadi floor. The plateau is represented </span><span style="font-family:Verdana;font-size:12px;">by the black basaltic sheet that contains some semi-rounded depressions filled with Quaternary eolian sands. The scarps of the main wadi and its tributaries are nearly steep and contain many asphaltic roads with some isolated cone hills detached from the scarps. Geomorphological, Wadi Qudaid</span><span style="font-family:Verdana;font-size:12px;"> represents the incomplete erosion cycle that begins with the formation of deep galleries and very steep