the formation of something is a kind of process & rock formation can be used to study the history of rocks on earth ->  studying rock formations can mean studying the history and processes of earth  studying rock formations can mean studying the history and processes of earth & structural geologists study rock formations ->  structural geologists study the history and processes of earth  fossils can be used to study the history of organisms and environments on earth & how earth 's environment changed is a part of the history of earth 's environment ->  studying fossils in rock formations can mean studying the history and processes of earth  studying fossils in rock formations can mean studying the history and processes of earth & paleontologists study fossils in rock formations ->  paleontologists study the history and processes of earth  structural geologists study the history and processes of earth & paleontologists study the history and processes of earth -> structural geologists and paleontologists both study the history and processes of earth