Grammar Dimensions, Book Three. Return to Top 3. Geology is the study of the earth. Geologists attempt to explain how the earth was formed and how it changes. Geologists also contribute to space exploration by advising scientists about potential lunar landing sites.
Scientists learn the age of rocks by measuring the amount of radioactive isotopes in the rocks.
They can approximate the age of a rock by comparing the amount of uranium and lead in the rock. A glacier is a huge mass of ice that moves slowly over land. Glaciers begin to form when more snow falls during the winter than melts or evaporates during the summer. The ice eventually becomes very thick and starts to move slowly under the pressure of its own weight. Applied English Grammar.