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Published in Tesfay Gebretsadkan Gebremicael, Understanding the Impact of Human Interventions on the Hydrology of Nile Basin Headwaters, the Case of Upper Tekeze Catchments, 2019
Tesfay Gebretsadkan Gebremicael
The majority of the geological formations are Enticho Sandstone, Edag Arbai Tillites, Adigrat Sandstone, Antalo Super sequence and Metamorphic (basement) rocks (Gebreyohannes et al., 2013; Virgo & Munro, 1977). The dominant soil types of the catchment are clay loam, sandy clay loam, clay, loam and sandy loam (Abraha, 2014; Zenebe et al., 2013). The occurrence of soil textures across the whole catchment is deeply weathered soil in the uppermost plateaus, rocky and shallow soils in the vertical scarps, coarse and stony soils in the steep slopes, finer textured soils in the undulating pediments and most deep alluvial soils are found in the alluvial terraces and lower parts of the alluvial deposits (Abraha, 2014; Gebreyohannes et al., 2013). Most of the soils in the basin are limited in depth due to contagious hard rocks and cemented layers and hence not suitable for agricultural production despite farmers having cultivated them for a long time because of shortage of arable land in the basin (Virgo & Munro, 1977).
Lexicon of lithostratigraphic units for the Sudan
Published in J.R. Vail, Lexicon of Geological Terms for the Sudan, 2022
Whiteman (1971a) considered the sediments passed laterally into sandstones in the Setit valley and thence into the Adigrat Sandstone, which underlie Upper Jurassic limestones in Ethiopia. He concluded the Gedaref Formation to be Middle or Upper Jurassic, and not Nubian (Cretaceous). This has not been substantiated.
Compositional characteristics and genetic affinity of the ferricrete deposit in Adi Kokeb district, northwestern Tigray, Ethiopia
Published in Applied Earth Science, 2019
Yeman Gebru, Anthony Azubuike Elueze, Kassa Amare, Franck Wilfried Nguimatsia Dongmo
The Tsaliet and Tembien groups underwent several phases of deformation that created a wide variety of texture, geological structures and mineral assemblages (Beyth 1972; Kazmin 1972; Avigad et al. 2007; Miller et al. 2011). The Tsaliet and Tembien groups are overlain by Paleozoic-Mesozoic sedimentary formations (Alene et al. 2006). From oldest to youngest, they are the Enticho Sandstone, Edaga Arbi Tillite, Adigrat Sandstone, Hintalo Limestone, Amba Aradom Sandstone and Agula Shale (Beyth 1971, 1972; Tadesse and Sawada 1999; Alene et al. 2006). This succession is overlain by thick Cenozoic volcanics including basalt, andesite, dacite, rhyolite, dolerite and tuffaceous rocks (Beyth 1971; Kazmin 1972; Tadesse and Sawada 1999). Volcanism continued with the erupted of a thick sequence of acidic lava flows through major fracture systems during the late Cenozoic and culminated in the formation of trachyte and phonolite plugs (Beyth 1971; Kazmin 1972; Tadesse and Sawada 1999). These plugs are a prominent topographic feature of the rugged and elevated surface in the central part of the region. During the Quaternary, thick alluvial deposits accumulated on low-lying areas in the western and southern parts of the region (Tadesse 1997). The Adi Kokeb ferricrete deposit is generally confined to regionally metamorphosed terrain comprising low-grade and altered meta-volcanic and meta-sedimentary basement rocks of northern Ethiopia. In some places, these assemblages (low-grade and altered meta-volcanic and meta-sedimentary basement rocks) are intruded by granitoids and overlain by Mesozoic ferruginous sandstone (Figure 2).
Mineralogical and geochemical characteristics of the iron–duricrust deposit in Adi-Daero area, northwestern Tigray, Ethiopia: implication for the origin and controlling factors
Published in Applied Earth Science, 2020
Yeman Gebru, Teklay Gidey, Bereket Gebresilassie, Tekia Hadgu
In the study area, an iron duricrust is developed on Mesozoic sedimentary rock (Adigrat Sandstone) which overlies basement meta-sandstone, with the Adigrat Sandstone regarded as bedrock for the purposes of this study. The ferricrete, 6 m thick, is uppermost in a profile that includes a clay-rich horizon (3–4 m thick). In the Adi-Daero area, an outcrops of a complete ferricrete profile are rare. However, detailed mapping of the area around the village of Adi-Daero and field observation of quarry sites and excavations, road cuttings, natural sections and marginal outcrops in the area permitted reconstruction of the entire ferricrete profile from the surface iron-rich duricrust to the underlying bedrock (Figure 2).
Characterization of hydro chemistry and groundwater quality evaluation for drinking purpose in Adigrat area, Tigray, northern Ethiopia
Published in Water Science, 2018
The Hydrogeological setup of the area is completely governed by the geomorphology and tectonics effects. Accordingly, the different geological unit exhibits different hydrogeological condition on the basis of topography, lithology and tectonics. The groundwater occurrence is anticipated dominantly in Enticho sandstone. The basalts and Adigrat sandstone underlain by impervious layer of Edaga Arbi glacial and hence the cliffs are completely drained not feed to the Enticho sandstone and they generate surface water. The metamorphic rocks are also groundwater reservoirs to some extent particularly at contact with overburden materials (Ermias et al., 2015).