Answer Key Geologic Time Scale Worksheet Answers

Toilet Paper Time Name:_____________________________________ Goal: To map out some important geological events in the Earth’s history using toilet paper. Pre-questions: Answer the following questions the best that you can. Use complete sentences! 1. How long ago did the dinosaurs live? 248-65 million years ago. 2. How long before that did Earth form? 4,352,000,000 years. 3. How long ago did humans appear on Earth? 100,000 years ago. 4. How do you think geologists know this? What evidence do they have? Answers will vary, but fossils was a popular answer. What to do with the Toilet Paper: Use the columns below (# of sheets and centimeters) to make marks on the toilet paper Hints:   Toilet paper is fragile! It will break if you are not careful. Use tape sparingly to fix any tears. You will have to write lightly or it will rip. # of Sheets Centimeters Predicted Event in Geological Time Prediction Using Teacher Word Bank Actual Event in Geological Time .000 .0005 .08 .000 .0005 .81 Present Day Present Day Present Day .50 2.0 5.08 20.32 2.50 25.397 3.25 33.02 3.25 11 33.02 111.76 12.25 14 16.25 18.15 124.46 142.24 165.10 184.41 24.5 28.5 248.92 289.56 Modern man Linking of North and South America Opening of the Red Sea Collision of India with Asia Separation of Australia and Antarctica Beginning of the Cenozoic Era Dinosaurs became extinct Opening of the Atlantic Ocean Mesozoic Era begins Final assembly of Pangea First reptiles Early trees, formation of coal deposits Early fish Early shelled organisms Years Ago 0 100,000 1,500,000 10,000,000 40,000,000 50,000,000 65,000,000 65,000,000 200,000,000 245,000,000 280,000,000 318,000,000 340,000,000 400,000,000 544,000,000 28.5 289.56 230 230 2,300 2,300 Beginning of the Paleozoic Era Precambrian Era Origin of Earth Origin of Earth Origin of Earth 544,000,000 4,600,000,000 4,600,000,000 When you finish marking your toilet paper: Now that your toilet paper has marks on it, try to guess what geologic event in Earth’s history happened at each mark. Think about what you know about events on Earth….what has developed, been formed, lived, died, etc. Fill in the column labeled “Predicted Event in Geologic Time” with your guesses. Class discussion: Answer the following and be prepared to share with the class: Choose 3 of the predicted events and justify why you put them where you put them.    Guided Predictions: Using the Teacher’s Word Bank, try to guess what geologic event in Earth’s history happened at each mark. Fill in the column labeled “Prediction Using Teacher Word Bank” Actual Answers: Listen now as your teacher tells you when stuff really happened! We will discuss the events for you to record and talk about how long ago they actually happened. Creation of your toilet paper timeline: Using the “Actual Event in Geologic Time” column, write the event next to the mark that you made earlier. Once again, write carefully as toilet paper rips easily! Post-Questions: 1. Why is a time scale used to represent Earth’s history instead of a calendar? 2. Looking at the 4 eras (Cenezoic, Mesozoic, Paleozoic, Precambrian) which one is the longest? Why would geologists divide the eras unequally? 3. What are 2 reasons we would want to know about Geologic Time? Word Bank Opening of the Atlantic Ocean Final Assembly of Pangaea Linking of North and South America Precambrian Time begins Mesozoic Era begins Dinosaurs become extinct Separation of Australia & Antarctica Collision of India with Asia Early trees, formation of coal deposits Modern Man on Earth Early shelled organisms Early Fish First reptiles Beginning of Paleozoic Era Beginning of Cenozoic Era Opening of the Red Sea Answer Key: sheets .000 sheets .0005 sheets .08 sheets .50 sheets 2.0 sheets 2.50 sheets 3.25 Sheets 3.25 sheets 11 sheets 12.25 sheets 14 sheets 16.25 sheets 18.15 sheets 24.5 sheets 28.5 sheets 28.5 sheets 230 sheets 230 sheets centimeters .00 cm. .0005 cm. .812 cm. 5.08 cm. 20.32 cm. 25.397 cm. 25.397 cm 33.02 cm. 111.76 cm. 124.46 cm. 142.24 cm. 165.10 cm. 184.41 cm. 243 .92 cm. 289.56 cm. 289.56 cm. 2,300 cm. 2,300 cm. Event Present Modern man Linking of North and South America Opening of Red Sea Collision of India with Asia Separation of Australia and Antarctica Beginning of Cenozoic Era Dinosaurs became extinct Opening of Atlantic Ocean Mesozoic Era begins Final assembly of Pangaea First reptiles Early trees, formation of coal deposits Early fish Early shelled organisms Beginning of Paleozoic Era Precambrian time begins Origin of earth yrs before present 0 10,000 1,500,000 10,000,000 40,000,000 50,000,000 65,000,000 65,000,000 200,000,000 245,000,000 280,000,000 318,000,000 340,000,000 400,000,000 544,000,000 544,000,000 4,600,000,000 4,600,000,000