A geologic time scale is an ordered arrangement of rock layers based on their ages. false a unit of geological time by which a period is divided. false a table that outlines Earth's development. true a unit of geologic time by which an era is divided. false Single A unit of geologic time that includes two or more periods. geologic column false epoch false eon false era true Single A unit of geologic time by which a period is divided. epoch true eon false era false geologic column false Single geologic column is a a table that outlines Earth's development. false an ordered arrangement of rock layers based on their ages. true a unit of geologic time by which a period is divided. false a unit of geologic time by which an era is divided. false Single Scientists created the first geologic column by determining the relative ages of sedimentary rock in one chosen area. false the area where life began. false North America false areas all over the world. true Single If the Cretaceous Period began about 146 Ma, this means it began... 146 billion years ago. false 146 million years ago. true 146,000 years ago false in the year 146. false Single Geologic time is divided into... two eons false three eons false four eons true five eons false Single Precambrian time consists of the first eon of Earth's history. false the last eon of Earth's history. false the first three eons of Earth's history. true 4 billion years between the first eon and the last eon. false Single A geologic period is usually named for a specific type of fossils. false the person who found the first fossils from the period. false the place where its characteristic fossils were first discovered. true the time in which the period occurred. false Single Name the four timeframes in order from oldest to youngest. Precambrian Time, Paleozoic Era, Mesozoic Era, Cenozoic Era true Mesozoic Era, Precambrian time, Cenozoic Era, Paleozoic Era false Paleozoic Era, Mesozoic Era, Precambrian Time, Cenozoic false false Single