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BIF > Geology > Geological Map, Page 2 < Previous page Next > |
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The geological formations are inter-layered with, and separated by, named geosols (fossil soils) which generally represent long periods of vegetation growth when dune building was inactive. Mapping of the geosols was critical to the production of the map, due to the similarity of adjacent limestone formations, such as the Lower Town Hill and Upper Town Hill, which make them almost indistinguishable in the field.
Older topographically more subdued formations form the core of the Bermuda islands. Later, topographically prominent formations are the product of limestone accumulation on the seaward flanks of the older limestones. The reason for this is that the aeolian sand dunes, of which Bermuda is built, are born on the coast of pre-existing land. For their growth, they depend on beaches as a source of sand and upon onshore winds for the landward transportation of that sand. Distinction of geologically "older" and "younger" Bermuda terraines was first proposed by Sayles (*****) < Previous page Next > |
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Young limestones |
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Old limestones |
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Oldest limestones |
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Simplified Geological Map of Bermuda
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The geological formations of Bermuda can grouped on the basis of topography and degree of alteration and cementation into three groups. The oldest group comprises the Walsingham formation. The old, or intermediate, group comprises the Lower and Upper Town Hill formations; and the young group comprises the Belmont, Rocky Bay and Southampton formations. (Vacher ***) |