Anatomy of a mountain: The Thebes Limestone Formation (Lower Eocene) at Gebel Gurnah, Luxor, Nile Valley, Upper Egypt

Abstract

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

Inferring Hypogene Karst at Depth from the Patterns of Non-Tectonic Syncline Networks in Eocene Limestones, Western Desert, Egypt

“…For this paper, we will use the same stratigraphic column (Figure 3B) that we presented in Tewksbury et al (2017a), which uses the Thebes Group nomenclature. Figure 3B also shows our best estimate for stratigraphic thicknesses under our study area based on recent work by King et al (2017), combined with data from the Assiut-Kharga well. Detailed rationale for both the stratigraphic (1981).…”

“…Depths to specific formations are based primarily on Assiut-Kharga well (Barakat and Asaad, 1965), located in the middle of our study area. Data from El-Azabi and Farouk (2011), King et al (2017), Said (1960, 1962, 1990), El Hinnawi et al (1978, Issawi (1972), Issawi et al (2009), , Khalil and El-Younsy (2003), El Hinnawi et al (2005). Reprinted from Tewksbury et al (2017a) with permission from Elsevier.…”

“…Much of the research by previous workers on the bedrock in this area of the Western Desert has targeted sedimentology, stratigraphy, paleontology, and geochemistry (e.g., King et al, 2017;El-Azabi and Farouk, 2011;Issawi et al, 2009 and references therein), and the general stratigraphy is well known. Lower Eocene shallow water carbonates cap the entire Limestone Plateau (Figure 1D) and dip beneath Oligocene and Miocene sedimentary cover in northern Egypt.…”

The Study of Application of Nano Fluid Synthases in the Treatment of Structural Disintegration and Architectural facades of Hatshepsut Limestone Temple in Deir El-Bahari

“…Ancient Egyptians constructed houses, palaces, temples and tombs mainly of environmental stones (Falana et al, 2020) and limestone and sandstone was the most commonly used materials in the construction of sacred buildings in Egypt because of its resistant to harsh weather. During the period of Queen Hatshepsut, Hatshepsut temple was built of local materials from Thebes limestone extracted from ancient quarry in Gebel Qurna (Aubry et al, 2009), (Pawlicki, 2017) (King, 2017). The study of Graue et al, (2007) revealed that severe deterioration results into the structural disintegration of rock masses, which is as a result of a clearly pronounced cataclastic overprint and has become a major structural problem since the tomb's origin.…”

Geophysical anomalies detected by electrical resistivity tomography in the area surrounding Tutankhamun's tomb

“…Conversely, the hill above the KV62 tomb is constituted both by limestone of the Thebes formation and by natural aerated debris from the valley sides. Further details on the geology and on the properties of the materials could be found for example in Wust and McLane, 2000;Aubry et al, 2009, Dupuis at al., 2011, King et al, 2017 and other references cited therein. This paper is organized as follows.…”