Climate WDNP is part of a hyper arid, hot desert area, which rarely receive any rainfall. The climate is extremely harsh. The summer maximum daily temperature can exceed 41.5 C while in winter daily sunshine warm weather and very low at night less than zero. The average monthly evaporation ranges from 7-2 mm/ day during December to 24.1 mm/ day January. The relative humidity generally low, ranging from 5 % in winter and up to 56 % in the summer. The wind direction generally is blowing from the north-west.
Geomorphology and Topography  According to the geomorphologic system of Egypt, the Farafra oasis lies within an oval shaped depression, which is bounded by scarps from the eastern, northern and western sides where, as it is open due to the south the longer axis of the depression is 102 km, where as, its east west axis measured near the middle of the depression is about 90 km. The depression is covers an area about 980 km2. The floor of the depression is covered by the Dakhla Formation in southern part. Northward covered by chalk of Maestrichtian age (Khoman chalk), and sand sheet with some sief dunes on top covers the eastern part of the depression. The WDNP is located in northern part of Farafra Depression the area has been under arid climatic conditions since the very late Pleistocene. Hence, erosional processes are mainly due to wind action temperature variation and occasional low rainfall. The general relief of the area is relatively low. The maximum height is about 353 m above sea level at El Quss Abu said south western part of the park, and the minimum reaches about 32 m above sea level at Wadi Hennis, Ain El Wadi and Wadi El Maqfi areas these areas are coverd by wet sabkha Geology:The beautiful landscapes of white Desert today ( mushrooms, towers, and shapes sometimes resemble mysterious animals, camels and sphinxes ) is a result of a very long depositional history under the various geological sedimentolgical regimes and palaeoenvironmental conditions, followed by the minor tectonic movements and finally by surface processes that etched the present beautiful landscape.
The rocks exposed in the White Desert National Park are of sedimentary nature and range in age from Cretaceous to recent. In general, stratigraphically rock units of White Desert can be easily divided into five sedimentary rock Formations in ascending order are the El Hefhuf, khoman, Abdullah / Tarawan, Esna shale and Farafra limestone Formations. These are brief notes on each of them: El Hefhuf Formation:
Age: (campanian)
Type section: Gebal Hefhuf, Bahariya oasis
Stratigraphic position: Underlie the khoman chalk and overlies the Bahariya formation of cenomanian age.
Lithology: El Hefhuf Formation is the oldest rock formation in White Desert, named by Said (1962). It is made up of white to grayish yellow sandstones shale sandy clay and following by phosphatic band and dolostone on the top.In the Wadi Hennis the El Hefhuf Formation is 35 m thick and made up of varicolored shale, clay, siltstone and sandstone intercalations, capped by a yellowish brown, hard, vuggy, crystalline phosphatic sandy dolostone bed 4 m thick contain badly preserved Ostrea sp and undefined shell fragments.
El Hefhuf Formation contains fossilized woods especially at Wadi Hennis and wadi El –Obeiyid.
The khoman Formation:
Age: early Maastrichtian
Type section: Ain khoman western Bahariya oasis
Stratigraphic position: It is conformably overlies the El Hefhuf Formation and underlies Abdullah limestone
Lithology: this formation made up of white chalk, were deposited here during the Late Cretaceous, about 70 million years ago, when the sea coverd the vast area of western desert and deposited of chalks reflect deep marine conditions, the chalk is characterized by a great number of joint filled with calcite veins, small iron – rich pipes and pyrite concretions. The floor of white desert are partly covered by small fragments of pseudomorphs of iron oxides after pyrite.
Abdullah limestone / Tarawan Formation
Age: (Late Paleocene)
Author: Le Roy 1953
Type section: Ain El Maqfi - White Desert National Park-(Frafra Oasis)
Stratigraphic position: overlies the Khoman Formation and underlies the Esna Formation
Lithology: thin bedded calcareous, chalky shale to argillaceous limestone chalky limestone with marl bands in some parts followed by gravels boulders and cobbles from limestone and chert.
Esna shale: late Paleocene – Early Eocene
Author: Beadnell 1905, Said 1960
Type section: Gebal Aweina ( Esna)
Stratigraphic position: overlies the Tarawan chalk and the Abdullah limestones and underlies the Frafra limestones.
Lithology : laminated green and grey shale and marl with carbonates intercalations, becoming more calcareous near top.
Farafra limestone (lower Eocene) include Nummulites sp
Author: Said 1960
Type section: El Quess Abu Said (south western part) of White Desert National Park
Stratigraphic position: overlies the Esna Shale Formation
Lithology: white to earthy grey, hard limestone
The limestone or chalks were deposited at the end of cretaceous period, when this entire region was under marine water.
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Geology
