Quaternary Period in Saudi Arabia

The publication of this first volume on the Quaternary Period in Saudi Arabia marks a significant milestone in the study of this Kingdom's basic geology. It also represents a major achievement in international cooperation in scholarship. The study of the Quaternary Period of Saudi Arabia was first proposed by Austrian scientists and by the officers of the Austrian Academy of Sciences early in 1972. A meeting was arranged between representatives of that Academy and of the University of Petroleum and Minerals, in Vienna, during May and June of that year, and tentative agreement was reached on the details of this cooperative venture. An exchange of letters, 15th June 1972 from the Austrian Academy of Sciences and 21th June 1972 from the Uni­ versity of Petroleum and Minerals, formally recorded the basis of the agree­ ment and arranged for the first visit to Saudi Arabia of the initial research team and accompanying officials from Austria. This team was headed by Professor Dr. JOSEF ZOTL, of the Department for Hydrogeology, Technical University of Graz, the initial project director. Many scientists, administrators, and officials have contributed to the success of this fundamental research project. Their number is too extensive to mention in this Foreword, but the principal contributors have been listed in the body of this text in conjunction with the specific areas of investigation in which they participated. The enormous contribution of Professor Dr. ZOTL, however, merits exceptional commendation.

Contenu

Acknowledgements.- 1. General Information on the Arabian Peninsula.- 1.1. Geology.- 1.1.1. Introduction.- 1.1.2. Structure and Geologic History of the Peninsula.- 1.1.3. Arabian Shield.- 1.1.4. Arabian Shelf.- 1.1.5. Mobile Belt.- 1.1.6. Red Sea.- 1.1.7. Economic Geology.- 1.2. Geomorphology.- 1.2. 1. Introduction.- 1.2. 2. Arabian Gulf Coastal Region.- 1.2. 3. As Summan Plateau.- 1.2. 4. Eolian Sand Areas.- 1.2. 5. Cuesta Region.- 1.2. 6. Central Plateau Region.- 1.2. 7. Mountains of Western Arabia.- 1.2. 8. Red Sea Coastal Plain.- 1.2. 9. Mountains of Southern Arabia.- 1.2.10. Oman Mountains.- 1.3. Climate.- 1.3.1. Introduction.- 1.3.2. Temperatures.- 1.3.3. Precipitation.- 1.3.4. Relative Humidities.- 1.3.5. Prevailing Wind Directions.- 1.3.6. Seasons.- 1.3.7. Solar Radiation.- 2. Regions of Investigation.- 2.1. Gulf Coastal Region and Its Hinterland.- 2.1.1. General Geology.- 2.1.1.1. Topography.- 2.1.1.2. Stratigraphy.- 2.1.1.3. Structure.- 2.1.1.4. Economic geology.- 2.1.2. Sea Level Fluctuations During the Quaternary Period.- 2.1.2.1. Prewürmglacial sea level fluctuations.- 2.1.2.2. Sea level fluctuations during the Würm time.- 2.1.2.3. Holocene sea level fluctuations.- 2.1.3. Geologic History of the Al Hasa Area Since the Pliocene.- 2.1.3.1. Terrestrial sedimentation of the Lower Pliocene.- 2.1.3.2. Pliocene-Pleistocene marine transgression and regression..- 2.1.3.3. Breakers terraces and caves of Jabal Al Qarah.- 2.1.3.4. The Pliocene/Pleistocene Delta of Wadi As Sah'ba.- 2.1.3.5. Quaternary erosion and sedimentation.- 2.1.3.6. Climatic and hydrologic conditions.- 2.1.4. Geomorphology of the Eastern Margin of the Shedgum Plateau.- 2.1.4.1. Introduction.- 2.1.4.2. Factors controlling the geomorphogeny.- 2.1.4.3. Landforms.- 2.1.4.4. Calcareous duricrust.- 2.1.5. Sabkhahs of Eastern Saudi Arabia.- 2.1.5.1. Introduction.- 2.1.5.2. Reconnaissance observations.- 2.1.5.3. Observations on Sabkhat Ar Riyas.- 2.1.5.4. Brine studies at Sabkhat Ar Riyas.- 2.1.6. Hydrochemical Investigations in the Areas of Al Qatif and Al Hasa With Some Remarks on Water Samples From Wadi Al Miyah and Wadi As Sah'ba Near Haradh.- 2.1.6.1. Al Qatif oases.- 2.1.6.2. Al Hasa oasis.- 2.1.6.3. Wadi Al Miyah.- 2.1.6.4. Wadi As Sah'ba near Haradh.- 2.1.6.5. Final remarks.- 2.1.7. Cluster Analyses of Water Wells of the Al Qatif and Al Hasa Areas.- 2.1.7.1. Introduction.- 2.1.7.2. Cluster analysis.- 2.1.7.3. Combined Al Hasa and Al Qatif areas.- 2.1.7.4. Al Hasa area.- 2.1.7.5. Al Qatif area.- 2.1.7.6. Discriminant analysis.- 2.1.7.7. Discussion.- 2.1.7.8. Appendix.- 2.1.8. Isotopic Composition of Waters of Al Qatif and Al Hasa Areas.- 2.1.8.1. Introduction.- 2.1.8.2. Deuterium and oxygen-18.- 2.1.8.3. Tritium.- 2.1.8.4. Carbon-14.- 2.1.8.5. Sulfur-34.- 2.2. As Sulb Plateau.- 2.2.1. General Geology.- 2.2.2. Karstification and Geomorphogeny of As Sulb Plateau.- 2.3. Wadi Ar Rimah.- 2.3.1. The Quaternary Development of the Upper Part of Wadi Ar Rimah.- 2.3.1.1. General remarks on wadi investigations.- 2.3.1.2. Geological conditions in the area of Wadi Ar Rimah.- 2.3.1.3. Geomorphological features.- 2.3.1.4. Quaternary sediments.- 2.3.1.5. The cycle of accumulation and erosion.- 2.3.2. Hydrogeological and Hydrochemical Investigations in the Upper Part of Wadi Ar Rimah 182.- 2.3.2.1. Hydrogeological conditions in Wadi Ar Rimah between Aglat As Suqur and 'Unayzah.- 2.3.2.2. Hydrochemical investigations and isotope measurements in the areas of Riyadh AI Khabra, Wadi Ar Rimah and Wadi Maraghan.- 2.4. Cuesta Region of the Tuwayq Mountains.- 2.4.1. General Geology and Stratigraphy.- 2.4.2. Accumulation Terraces of Wadi Hanifah and Wadi Al Luhy.- 2.4.2.1. Morphological and sedimentological features.- 2.4.2.2. Paleontological description of Gastropoda.- 2.4.2.3. Biogeographic and ecological aspects.- 2.4.3. Wadi Birk.- 2.4.3.1. Wadi deposits.- 2.4.3.2. Accumulation terrace in the area of Al Hawtah.- 2.4.3.3. Morphogeny of Wadi Birk.- 2.4.4. Chemistry and Isotope Content of Some Wadi Groundwaters in the Central Parts of the Tuwayq Mountains.- 2.4.4.1. Wadi Hanifah, Wadi Nisah, Wadi Al Luhy.- 2.4.4.2. Wadi Al Hawtah, Wadi Birk.- 2.4.4.3. The ? D-? 18O relation of waters in the central parts of the Tuwayq Mountains.- 2.5. Wadi Ad Dawasir and Its Hinterland.- 2.5.1. General Geology ).- 2.5.2 Quaternary Studies on the Recharge Area Situated in Crystalline Rock Regions.- 2.5.2.1. Wadi Ranyah between the villages of Al Amlah and Rawdhah.- 2.5.2.2. Age determination of basalt rocks and its significance in the reconstruction of climate conditions during the Quaternary.- 2.5.2.3. Ranyah-Bishah accumulation plain.- 2.5.2.4. Wadi Bishah's lower part.- 2.5.3. Studies of the Quaternary Development of the Eastern Part of the Recharge Area of Wadi Ad Dawasir.- 2.5.3.1. The area between the oases of Al Khamasin and Al Lidam.- 2.5.3.2. The break-through in the Tuwayq Mountains.- 2.5.3.3. The wadi's transition into Ar Rub' Al Khali.- 2.5.4. Hydrochemical investigations and Measurements of the Content of Isotopes of Wells in Wadi Ad Dawasir.- 2.6. Ar Rub' Al Khali.- 2.6.1. Introduction.- 2.6.2. Stratigraphy and Sedimentation.- 2.6.2.1. Geomorphic processes.- 2.6.2.2. Late Quaternary history.- 2.6.2.3. Late Pleistocene lakes.- 2.6.2.4. Holocene lakes.- 2.6.3. Paleoclimate.- 3. Summary and General Conclusions.- 3.1. Quaternary Sediments.- 3.1.1. Scope of Investigations.- 3.1.2. Sedimentation in Wadis.- 3.1.2.1. General conditions of accumulation.- 3.1.2.2. Description of sediments.- 3.1.3. Sediments in the Area of Vast Accumulation Plains.- 3.1.3.1. Alluvial fans.- 3.1.3.2. Sand dunes.- 3.1.3.3. Lacustrine deposits.- 3.1.3.4. Duricrust.- 3.1.4. Marine Sediments and Sabkhahs in the Coastal Region of the Arabian Gulf.- 3.1.5. Chronological and Stratigraphic Classification of Processes of Erosion and Sedimentation During the Quaternary.- 3.1.5.1. Development of the drainage system.- 3.1.5.2. Processes of marine transgressions.- 3.1.5.3. Age determination of the sequence of sediments.- 3.2. Climatic Changes During the Quaternary Period.- 3.2.1. Holocene.- 3.2.2. Climatic Fluctuations During the Würm.- 3.2.3. Prewürm Pleistocene.- 3.2.4. Geochronological Delimitation and Division of the Quaternary.- 3.2.5. The Late Pliocene/Early Pleistocene Phase.- References.- Index of Geographical Names.- Transcription of Names Used in Some Figures.