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The western foothills of the mountain are where the tourist site of Rosh Hanikra is located. This mountain is part of the Galilee mountain ridge, and is the only ridge in Israel which continues westward to the sea, descending into it in a steep cliff without a flat sand strip.
From a geomorphological point of view, the cliff of Rosh Hanikra consists of three layers:
The bottommost layer is made of hard limestone most of which is under sea level. The underwater grottoes were quarried out of this layer.
The middle layer is a steep cliff which reaches a height of 60 meters. This is a light colored rock made of soft chalk (a soft sea rock sediment) lined with rows of dark flintstone which developed in the era when the sea was warm and shallow. As a result, seaweed and marine life were discharged forming and consolidating into the flintstone.
The chalk is a rock made of calcite low in magnesium which does not dissolve and remains soft. Calcite has tiny pores through which water cannot penetrate and it can withstand erosion and therefore there is a landscape of steep cliffs at the point where the chalk ridges come into contact with the sea.
The chalk supplies building material and land rich in lime good for fertilizing fields. The white chalk once favored by teachers to write on class blackboards is essentially this kind of chalk.
On this part of the cliff a different sort of destruction is going on: The rock surface is covered at many points with thin crust and a white dust which are the result of the ongoing crumbling of the outer rock layer. This disintegration is helped along by salt carried on the sea spray throughout the year.
The outer layer is made of hard dolomite. Dolomite is a kind of sediment or residue rock, much like limestone in its composition and characteristics. However, unlike chalk, dolomite is very porous allowing water to seep in. Dolomite is rather common in Israel, found mostly in the earth's crust.
This material was provided by: Uri Usri – a member of Kibbutz Rosh Hanikra and Mishal Gershon – a tour guide at the "Riders' Experience" farm club.
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