Bedded chert in Cyprus

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Governor’s Beach in the southern coast of Cyprus exhibits a nice exposure of interbedded chalk and chert. Chalk is soft, porous, and fine-grained marine limestone composed of calcareous tests of various microorganisms.

Chert is dense and hard sedimentary rock, consisting mostly microcrystalline quartz. These rocks may frequently occur together. Chert is either nodular or forms layers (bedded chert).

Siliceous material forming chert layers is thought to represent siliceous material deposited on the seafloor and consisting of siliceous tests of radiolarians and diatoms which upon burial formed chert.

An outcrop of bedded chert and chalk
White chalk and gray chert. Chert layers stand out because they are much harder than soft chalk layers.
Bedded chert boudinage
An example of boudinage — chert layer seems to be stretched, it is not anymore continuous.
Close-up of chert layer
Close-up of chert layer
Flint in Cyprus
Chert between slightly brecciated chalk. Sometimes chert that occurs in chalk is named flint. This term does not have a precise definition but it is often reserved for pure and very hard chert examples. Hence, I would hesitate to name that way the examples shown above (and in the middle of this boudin) but this dark gray chert boudin probably qualifies. So, let’s say it is flint.

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