U-Pb zircon ages and geochemical data for the Monumental Granite and other granitoid rocks from Aswan, Egypt: implications for the geological evolution of the western margin of the Arabian Nubian Shield

Abstract

U-Pb zircon ages and geochemical data are presented for Pan-African granitoid rocks sampled in the area of Aswan, Egypt, close to the inferred boundary between the Saharan Metacraton and the Arabian Nubian Shield. The sample set includes tonalitic gneisses as well as undeformed, post-tectonic tonalites to granites (Aswan Tonalite, Monumental Granite, High-Dam Granite, Saluja-Sehel Granite). A tonalitic gneiss with a volcanic-arc type geochemical signature gave a zircon age of 622 ± 11 Ma, while the Aswan Tonalite and the Monumental Granite intruded at 606 ± 1 and 606 ± 2 Ma, respectively. The age of the High-Dam Granite was constrained at 595 ± 11 Ma. These data imply that the western parts of the Arabian Nubian Shield were accreted to the Saharan Metacraton prior to 606 Ma in the area of Aswan, most probably between 630 and 615 Ma.