We present a review of archaeological and geological studies on the West Bank as a basis for discussing the geological setting of the tombs and geologically related problems with a view to providing archaeologists with a framework in which to conduct their investigations on the restoration, preservation and management of the antique monuments. Whereas the geology of the Upper Nile Valley appears to be deceptively simple, the lithological succession is vertically variable, and we have recognized and defined several new lithological units within the upper Esna Shale Formation. We have been able to delineate lithological (shale/limestone) contacts in several tombs and observed that the main chambers in some were excavated below the Esna Shale in the Tarawan Chalk Formation. We have been able to document changing dip in the strata (warping) in several tombs, and to delineate two major orientations of fractures in the field. Investigations behind the Temple of Hatshepsut, in the Valley of the Kings and around Deir El Medina have revealed four broad regional structures. We confirm that the hills located near the Nile Valley, such as Sheik Abdel Qurna, do not belong to the tabular structure of the Theban Mountain, but are discrete displaced blocks including the Thebes Limestone, as supported by Google Earth photographs.

32We present a detailed geologic study of the Thebes Formation at Gebel Gurnah in its locus 56Key words: Thebes Limestone, Lower Eocene, Gebel Gurnah, Egypt, sequence stratigraphy. 58 59 I-Introduction 61The Lower Eocene* Thebes Formation is one of the thickest (~340 m) and regionally extensive 62 outcropping lithostratigraphic units of Egypt (Snavely et al., 1979; Fig. 1). Extending from the 63Farafra Oasis in the west to Upper Egypt (mostly between Qena-Esna) and beyond to the Red 64Sea coast and the Sinai in the east (Fig. 2) 67Despite this vast distribution, the geology of the formation remains poorly elucidated, and 68 contradictory interpretations have been given of its age and depositional environment. 69The type section of the Thebes Formation is at Gebel Gurnah, in the prominent limestone cliffs 70 on the west side of the Nile Valley, opposite the town of Luxor, which form the "Thebes 71Mountain" (Fig. 3). Since formal designation by 76(e.g., Rutherford et al., 1977;Curtis, 1979; see Aubry et al., 2008 see Aubry et al., , 2015 see Aubry et al., , 2016 III-a-Location 197On the West Bank of the Nile, opposite Luxor, the Sahara plateau nearly reaches the alluvial 198 plain (Fig. 3). There, prominent cliffs mainly constituted by the subhorizontal outcrops of the 229The section was first measured by C. Dupuis and W. Fathy with a Jacob's staff that corrects for 237The logging of the section is based mainly on macroscopic examination, aided by low-power 238 magnification (hand-lens), where needed. The Thebes Formation is mostly comprised of 239 limestones (Fig. 8 283Small quantities of gypsum, anhydrite and halite were recorded sporadically. Gypsum and 284anhydrite, which are omnipresent in the outcrops as small veins, are interpreted as weathering 285products of pyrite and they are not regarded as primary components of rocks. The presence of 286 halite, which is rather frequent at joints, is due to the current arid climate of Egypt. Neither of 287 these three minerals was considered in the calculation of the composition of the whole rocks. 288The only flint (from Subunit B6) that we have analyzed here contains 12% quartz. This quartz is 294Clay mineralogy 295Classical laboratory techniques, methodologies and procedures were adapted from Holtzappfel (1985). Samples were first decalcified using a 10% HCl solution and then deflocculated. The <2 296

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In order to cope with the rise in human-caused demands, Saudi Arabia is exploring new groundwater sources. The groundwater potential of Wadi Ranyah was studied using a multi-dataset-integrated approach that included time-variable gravity data from the Gravity Recovery and Climate Experiment (GRACE), vertical electrical sounding (VES), and time-domain-electromagnetic (TDEM) data with other related datasets to examine the variations and occurrence of groundwater storage and to define the controlling factors affecting the groundwater potential in Wadi Ranyah in southwestern Saudi Arabia. Between April 2002 and December 2021, the estimated variation in groundwater resources was −3.85 ± 0.15 mm/yr. From 2002 to 2019, the area observed an average yearly precipitation rate of 100 mm. The sedimentary succession and the underlying fractured basement rocks are influenced by the structural patterns that run mainly in three different trends (NW, NE, and NS). The sedimentary cover varies from 0 to 27 m in thickness. The outputs of the electrical sounding revealed four primary geoelectric units in the study area: on top, a highly resistant geoelectrical unit with a resistivity of 235–1020 Ω.m, composed of unsorted, loose, recent sediments; this is followed by a layer of gravel and coarse-grained sands with a resistivity of 225–980 Ω.m; then, a water-bearing unit of saturated sediments and weathered, fractured, basement crystalline rocks with a resistivity of 40–105 Ω.m, its depth varying from 4 to ~9 m; and then the lowest fourth unit composed of massive basement rocks with higher resistivity values varying from 4780 to 7850 Ω.m. The seven built dams store surface-water runoff in the southwestern part of the wadi, close to the upstream section, in addition to the Ranyah dam, as the eighth one is located in the middle of the wadi. The subsurface NW- and NS-trending fault lines impede the groundwater from flowing downstream of the wadi, forming isolated water-bearing grabens. Minimal surface runoff might occur in the northern part of the wadi. The combined findings are beneficial because they provide a complete picture of the groundwater potential of Wadi Ranyah and the controlling structural patterns. Using this integrated technique, the groundwater potential in arid and semiarid regions can now be accurately assessed.

One of the major geoenvironmental problems in the Kharga region arises from the haphazard exploitation of groundwater resources and sewage dumping, which have resulted in wastewater accumulation in the form of ponds. The impact of the spatial expansion of wastewater ponds in Kharga and the surrounding area has been so pervasive that ponds have become a source of environmental degradation. These ponds are distributed throughout the area, but the major lakes are located in the eastern and southeastern provinces. The water levels of these ponds are rising at a remarkable rate, especially in the winter, when there is no evaporation and rainfall can lead to overflows that flow towards cities, villages and farmlands. As a result of untreated sewage inflows, all the low surrounding spaces are at high risk of being influenced by these ponds. The objectives of this study were to evaluate the spatiotemporal threats posed by wastewater ponds and develop a conceptual model to estimate the geoenvironmental impacts on the surrounding areas. GIS and remote sensing were used to process all available geological, topographical, hydrogeological, hydrological, land use and environmental data. The pond expansion trend was estimated from Landsat time series from 1984 to 2018, and the results indicated that the wastewater bodies continuously increased and the land cover percentage decreased. The encroachment of wastewater ponds has resulted in extensive land cover disturbances in recent years, and land use change has affected nearly 2.5% of the region. The complexity of the problems associated with wastewater ponds in the Kharga district requires a comprehensive management plan that is effective in not only maintaining the stability of the ponds but also in improving the sociocultural and economic conditions around the ponds. Specifically, the wastewater drainage and accumulation system should be managed according to the surrounding functional context.