LOSS OF GEODIVERSITY
Map 1: Location map for Bahariya and Farafra oases in the Western desert- Egypt.
this volcanic activity in northern Egypt was related to renewed tension along African (northwest-trending) subcrustal lineaments, an idea also endorsed by Salem (1976).
III. Bahariya and Farafra Oases
The Western Desert of Egypt contains many unique geologic features consid- ered worthy of protection under the legal framework outlined above. Two such examples being Bahariya and Farafra Oases which are on the protected areas list due their geologic and archaeologi- cal importance, and also form one of the recorded Geoheritage places in Egypt (Map 1 on page 50).
In the Bahariya Oasis, 10 geologi- cal heritage types are established, namely stratigraphical, paleontologi- cal, sedimentary, igneous, mineral- ogical, economical, paleogeographical, geomorphological, hydrological and hydrogeological, and pedological types. In the Farafra Oasis and vicinity, only geomorphological and hydrological and hydrogeological types are found. In the area between these oases, sedimentary, mineralogical, paleogeographical, and geomorphological features occur includ- ing chalk and nummulitic limestones along with invertebrate and dinosaur remains (Plyusnina et al. 2016).
Cultural heritage sites date from pre- historic times to the recent past. In terms of biodiversity the relict oasis habitat represents some of the largest extents of remaining natural vegetation in the Western Desert. The region includes assemblages of fauna and flora charac- teristic of the Saharan biome, including several rare and highly endangered biological components.
The area in and around the Bahariya and Farafra Oases has been pivotal in many geological studies of structural
48 TPG •
Oct.Nov.Dec 2017
geology, stratigraphy, iron ore deposits, sedimentology, paleontology, geoarchae- ology (e.g. El-Akkad and Issawi 1963, Catuneanu et al. 2006, Khalifa and Catuneanu 2008, Tanner and Khalifa 2010, Salama et al., 2012, Afify et al. 2015). The White Desert Protected Area (Map 2) is located in one of the most attractive and astonishing landscapes of Egypt, where limestone erosional fea- tures create a spectacular landscape that has made the region world famous. These karst landforms include fine examples of relict towers that were formed during past wetter climatic conditions, and are now being degraded in the modern desert climate. Plyusnina et al., (2016) stated that the area is listed as being of global geo-heritage importance.
The most important geologic features that we have shown to be subject to loss or degradation are (Map 2):
foraminiferal zones). An open marine, warm Tethyan outer shelf environment of deposition is inferred (Abdel-Kireem & Samir,1995).
3. Crystal Mountain: The Crystal Mountain is situated between the Baharyia Oasis and the Farafra Oasis, in the northern White Desert. Despite its name, the Crystal Mountain is rather a ridge or hill sparkling like a crystal. There are well-exposed caves and paleokarst topography developed within the mas- sive Maastrichtian Khoman chalk. The paleokarst topography comprises huge collapse breccias, composed of meter- sized rounded chalky limestone blocks, and paleocaves with columnar-shaped stalagmites. The outer surfaces of the breccias are surrounded by concentric layers of stratified centimetre-sized tri- gonal clean calcite crystals. Black to dark brown impurities occur between and along the crystal boundaries. The paleocaves are also rimmed with calcite crystals. The caves seem to be devel- oped around brecciated blocks that later on dissolved leaving concentric layers of secondary coarse crystalline calcite around the voids left by the leached blocks. Some of these caves are filled with laminated reddish colored clay, silt and coarse sand of channel origin (cave floor fill). The caves were probably pro- duced by episodes of subaerial exposure during the multiple exposure events known from Maastrichtian through Oligocene time. The paleoclimate dur- ing this period in Egypt was consider- ably wetter, with monsoonal and even tropical rain forest climates during the late Eocene and Oligocene (Bown and Kraus, 1988).
4. Sulfur hot springs: Thermal min- eral springs are present in the oases,and are used for natural therapy.
Map 2: Location map for the selected geosites.
1. The Black Desert: This consists of ferruginous sandstones and shales which outcrop in the bottom of the depression. The siliciclastic beds of the Bahariya Formation are weathered into black conical-like hills, capped with basalt.
2. The White Desert: Limestone erosional features create a spectacular landscape that has made the region world famous, the snow-white nummu- litic chalky limestones of lower Eocene age. The white limestone of the Khoman Formation is dated as middle to lat- est middle Maastrichtian (Gansserina gansseri and Contusotruncana contusa
5. Dinosaur traces: at the bottom of the Bahariya Depression were found the remains of four immense and entirely new dinosaurs, along with dozens of other unique vertebrate specimens. All skeletons were removed from the place for scientific purposes and there remain only some traces.
IV. Geodiversity loss and threats:
In the last 10 years a great loss of geodiversity has been observed in the area: in some places this has resulted from incomplete removal and destruc- tion of geological features. Even though there is some weathering and erosion in
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