Geologic Time Scale

Master the Geologic Time Scale: Eras, periods, and facts vs. opinions for 7th-grade science.

Task 1: Read "Tic-Toc-Time" and answer the review questions. What is geologic time scale? When we use events instead of years to describe the history of Earth the biggest piece of time used to describe Earth's history the smallest piece of time used to describe Earth's history when we use groups of years to describe Earth's history Match the division of time with the correct description. Era The 2nd biggest unit of time used to describe Earth's history Period The 3rd biggest unit of time used to describe Earth's history Eon The biggest unit of time used to describe Earth's history Task 2: Watch the video introduction to "Geologic Time Scale" and answer the review questions below. What is the objective of the video? To learn the different eras and periods on the geologic time scale According to the video, how long ago did Earth form? 4.6 million years ago 4.6 billion years ago The geologic time scale is divided into intervals based on events that have occurred. The geologic time scale is divided intoSelect all that apply!!! columns periods rows eras epochs The time period from 4.6 billion years ago to 570 million years is called the _. Paleozoic Precambrian Cenozoic Mesozoic The Paleozoic era is divided into _ periods. 3 4 5 7 The mesozoic era, also know as "The Age of Reptiles," began 252 million years ago and lasted until 66 million years ago. Which era is is known as "The Age of the Mammals," and the current era? Paleozoic Mesozoic Cenozoic Do all eras last for the same amount of time? yes no Task 3: Scientific Explanations- Scientist have to use facts when they explain the events that occurred in Earth's history. Can you tell a fact from an opinion? Basing ideas on facts is essential to good science. Review the summary image and complete the sorting activity. Look at the following list. Identify if each statement is a fact or not a fact. FACT The average global temperature has risen since 1900. LeBron James has won four NBA championships. Earth is 4.6 billion years old. NOT A FACT Lebron James is the greatest of all time. Climate change is the most serious danger that humans face today. Earth is really old.