How might a geologist study the history of earth

Geology is the study of what the earth is made of, its structure, materials, the processes affecting it and the organisms that inhabited the earth. A geologist may study the history of the earth by learning about the organisms and events in the past, how they changed over time, and how they may affect the future.

Geologists are the people who study the Earth's structure and its variations. Since the existence of rocks and their formation inside the earth is an evolutionary process therefore geologists need to study the history of earth. Similarly the formation of volcanoes, weathers, fossil fuels, minerals and related elements also came into being with a long span of time therefore the history of earth is also important for geologists to study.

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the thirteen colonies are:

connecticut, delaware, georgia, maryland, massachusetts, new jersey, new york, new hampshire, north carolina, pennsylvania, rhode island, south carolina, virginia