eduzhai > Physical Sciences > Earth Sciences >

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

  • carsar
  • (0) Download
  • 20210408
  • Save

... pages left unread,continue reading

Document pages: 29 pages

Abstract: Wadi Qudaid is located inthe west central part of Saudi Arabia. It about 135 km to the northeast of Jeddah city along Al Harameinhighway and it represents the upstream of the very large alluvial plain alongthe Red Sea coast. It runs in NE direction parallel to many wadis of the westcentral part of Saudi Arabia i.e. Wadi Fatima, wadi Sitarah. The wadi floor is filled by Quaternary depositswhich represent good groundwater aquifer. Geologically, the present-dayresidual landforms of Wadi Qudaid are composed mainly of Precambrian Arabiashield rocks overlained by Tertiary sedimentary rocks and finally harrat(Tertiary volcanic). The Precambrian rocks are represented by 1) a lowerlayered basic and intermediate volcanic and the intercalated volcaniclastics.This unit is correlatable with Samran Group, 2) an upper layered acidicvolcanic and the intercalated acidic volcaniclastics. The Arabian shield rocksare intensively folded and dragged along the major NE faults. They are directlyoverlain by Tertiary basic volcanic (harrat) and the related volcanoclastic redbeds). The main geomorphologic elements of the study area include plateau, scarps, and the wadi floor. The plateau isrepresented by the black basaltic sheet that contains some semi-roundeddepressions filled with Quaternary eolian sands. The scarps of the main wadiand its tributaries are nearly steep and contain many asphaltic roads with someisolated cone hills detached from the scarps. Geomorphological, Wadi Qudaid represents the incomplete erosion cycle thatbegins with the formation of deep galleries and very steep and narrow wadiesformed along the major NE faults and related fractures and folds. The progressof the erosion processes led to the formation of narrow interfluves as a resultof pedimentation and sculpturing of the wadies sides by scarp retreat. Thepeniplanation stages of the erosion cycles are reached in the southwestern andthe central part of the wadi where fast peniplained areas were formed. Theresults of this study revealed the role of the different geological processes(lithology, structural elements and climatic conditions) in the distribution ofpresent-day human populations in urban extensions. Qudaid, Dhubaya-Jumah, Dabyah,Al Khamrah, Almansa and Al Massamah are the mainvillages of Wadi Qudaid area.

Please select stars to rate!

         

0 comments Sign in to leave a comment.

    Data loading, please wait...
×