High School

This common, useful form of limestone consists of microscopic marine plankton shells. Thick Cretaceous-age deposits of this limestone in southeastern England are world-famous.

Which type of limestone is described here?

A. Chalk
B. Flint
C. Travertine
D. Siliceous silt

Answer :

A. The type of limestone described is chalk and Chalk is made up of microscopic marine.

Plankton shells and is prominent in the White Cliffs of Dover in southeastern England. Chalk is composed of microscopic marine plankton shells known as coccolithophores. Famous deposits of this type of limestone from the Cretaceous age are found in southeastern England, including the well-known White Cliffs of Dover.

Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Option a is correct.