Chapter 29, Problem 20TE

To determine

The reason for the wide distribution of Paleozoic marine sedimentary rocks such as limestone and dolomite in the continental interiors.

Answer to Problem 20TE

Due to the presence of shelled organisms in continental interiors marine sedimentary rocks such as limestone and dolomite are widely distributed in those areas.

Explanation of Solution

In the Paleozoic era, there was a rise in sea level. Therefore, shallow seas began to cover the continents leading to the flourishing of more marine life.

Most of the organisms in the shallow seas developed the capacity to secrete calcium carbonate and calcium phosphate, forming outer shells protecting them from harmful radiation. When these shelled organisms died, their shells and skeleton debris were amazed to form sedimentary rocks. In this way, sedimentary rocks like limestone and dolomite were formed in the shallow waters or continental interiors.

Conclusion:

Therefore, due to the presence of shelled organisms in continental interiors marine sedimentary rocks such as limestone and dolomite are widely distributed in those areas.