Fossil Mountain area
On the western side of the mountains, there are inliers of Cretaceous to Neogene (Miocene) rocks. These inliers are mainly in the southern half of the area, and although usually within a few kilometers of the mountain front, can be found up to 20 km to the west of the mountains. They occur as isolated rises and hills surrounded by alluvium and sand dunes. The different kinds of bedrock in the mountains influence the composition of alluvial fans on both the east and west sides of the mountain range.
In a few places there are rising dunes where sand is being blown up the sides of hills and mountains. These are common along the Fayah Range near Quarn Nazwa and also along the western side of the Hajar Mountains around Manama.
Fossil Mountain area
On the western side of the mountains, there are inliers of Cretaceous to Neogene (Miocene) rocks. These inliers are mainly in the southern half of the area, and although usually within a few kilometers of the mountain front, can be found up to 20 km to the west of the mountains. They occur as isolated rises and hills surrounded by alluvium and sand dunes. The different kinds of bedrock in the mountains influence the composition of alluvial fans on both the east and west sides of the mountain range.
In a few places there are rising dunes where sand is being blown up the sides of hills and mountains. These are common along the Fayah Range near Quarn Nazwa and also along the western side of the Hajar Mountains around Manama.