Earth’s Age + Evidence

WARM UP Write your homework – leave it to be stamped! Get your homework out to be checked! Update your Table of Contents for today! Get something to grade your Vocab Quiz with! DateSession # ActivityPage # 11/15 & 11/18 7Earth’s Age & Evidence Note guide 13 The Great Fossil Find Poster Instructions 14

Notes Tips for Today Anything in yellow you MUST write on your note guide Pictures and diagrams are great things to draw to help you remember vocab and ideas! Underlined or bold words that are underlined or bold in PowerPoint BECAUSE THEY ARE IMPORTANT !

How old is the Earth? Earth is around 4.6 BILLION years old.

BIG QUESTION: HOW DO WE KNOW HOW OLD THE EARTH IS?

BIG ANSWER: Everything coming up in the next few lessons provides an answer to the BIG QUESTION!

Law of Superposition Law of Superposition– Under normal conditions, the layers of sediment get older the deeper you go

Examples of Law of Superposition Just like a layered cake…you put the bottom layer down first, so it is the “oldest” and you fill in each layer on top of it! What examples can you come up with? Draw your own picture illustrate the concept!

We Have a Problem… There are several things can mess up the Law of Superposition called unconformities Types of unconformities: 1 – intrusion 2 – overturning 3 - faults

Unconformity Unconformity- A break or an irregularity in the geologic time sequence due to a geologic event. “Missing Information”

1. Intrusion An intrusion is igneous rock that cuts through layers of sedimentary rock. The intrusion is younger than any other rock layer it cuts through. intrusion

2. Overturning Overturning is when rock layers are folded due to gravity, erosion, or shifts in Earth’s crust.

3. Faults Faults are cracks, fractures or shifts in Earth’s crust Fault

Law of Superposition Practice Which type of unconformity do you see in the diagram? Can you put the layers in order from oldest to youngest?

Law of Superposition Practice Which types of unconformity do you see in the diagram? Can you put the layers in order from youngest to oldest?

What is This?

Fossils Fossil – traces or remains of living things from long ago that help sort out the sedimentary rock record Index Fossils – common fossils that are used as a “reference” to date other fossils

Types of Fossils BrainPOP Video

The Great Fossil Find Choose a partner to work with…I will give you 1 minute to move all of your stuff so that you are sitting with your partner and be ready to listen! Work together to determine what type of animal your fossil is! The activity guide must be turned in by the end of class! r.fs.fd.html

Homework 1.Bring a bag of Skittles next class! 2.The Great Fossil Find Poster due in 2 classes!

Warm-Up Write your homework – get it stamped! Update your Table of Contents for today! Make sure you have a cup of Skittles – you may need to arrange for someone to share with you! DateSession # ActivityPage # 11/19 & 11/20 8 Determining Age Note Guide15 Skittles Half-Life Simulation16 “Other Ways of Determining Age” Reading Comprehension & Activity 17

Review What were some things we talked about last class that help us determine how old Earth really is?

The Butler walks to work The Handyman rides a bike The Cook rides a motorcycle The Maid drives a car The Nephew has a seeing-eye dog

R (layer E)

R

Time for more specific evidence…

Relative Age Relative Age - the age of an event or object in relation to other events or objects – Use words like older, younger, around the same time, etc…

Absolute Age Absolute Age - The actual age of an event or object –Use techniques to figure out actual age Radioactive dating, carbon dating Lived: 1 million years ago 2 million years ago 3 million years ago 4 million years ago

Types of Dating Radioactive (Radiometric) Dating – If you know how much radioactive material was initially present in the sample and you know the half-life of the material, you can calculate the age of the sample. Carbon Dating – Using the amount of carbon in fossil remains, and the half life to determine the age - sample must have been alive to use carbon dating!

What’s a “half-life?” Half-life – the length of time it takes for half of the atoms in a sample of a radioactive material to change This break down occurs at a constant rate depending on the substance

Carbon Dating BrainPOP Video – Carbon Dating Half-life Practice

Skittles Half-Life Simulation You will work where you are seated, but you and your table partner can work together. I want to see your work before you leave, and I will be checking it off for a grade…then you can tape it into page 16!

Homework The Great Fossil Find Poster – due next class! Finish the “Other Ways of Determining Age” Reading, Questions & Activity – due in 2 classes!

Warm-Up Write a homework reminder – get it stamped! Update your Table of Contents for today! Put your Great Fossil Find Poster in the basket! Get your Skittles Lab out from last class! DateSession # ActivityPage # 11/21 & 11/22 9 Silent Stations Answer Sheet – FORMAL GRADE 18

Skittles Half-Life Simulation Review #2 on the back What is Iodine-131? # of Half-LivesTime of Half-LifeAmount of Iodine-131 Remaining 0040 mg 18 days20 mg 216 days10 mg 324 days5 mg 432 days2.5 mg

Skittles Half-Life Simulation Review #3 on the back: Does it give the name of the radioactive isotope in the question? What does it mean to be radioactive? What is an isotope? What is a half-life? What is the half-life of this isotope? What is the significance of this half-life – in other words, why should your mom not be worried?

READY TO FIND OUT WHAT THE GREAT FOSSIL FIND WAS? Scaphognathus crassirostris was a pterosaur, similar to a pterodactyl, that lived during the Late Jurassic Period.

Scaphognathus crassirostris What it may have looked like…

“SILENT STATIONS” You will rotate around the room quietly and practice the concepts we have learned at each station. I am the “Answer Key Station,” so once you have completed everything you can come check your answers! Be sure to tape the station guide into your notebook on page 18 once you have checked your answers and been checked off for a grade! Complete the homework for next class, or work on an extra credit opportunity!!

HOMEWORK “Other Ways of Determining Age” – Article, Questions & Map Activity due next class! Extra Credit Opportunity – try to finish it by after Thanksgiving break so you don’t forget about it!

Warm-Up No homework over break! Update your Table of Contents today! Get your “Other Ways of Determining Age” out to be checked! If you haven’t shown me your Silent Stations you need to have those out as well! DateSession # ActivityPage # 11/25 & 11/26 10Ice Cores & Tree Rings – Notes and Lab 19

Just a Few More Pieces of Evidence… We’ve already talked about: Law of Superposition Unconformities (Intrusion, Overturning, Fault) Fossils/Index Fossils Absolute & Relative Age Carbon Dating & Radioactive Dating We are missing: Ice Cores Tree Rings

Remember The Law of Uniformitarianism? The earth is a constantly changing place. Climate change is part of that and the climate can gradually change over hundreds, thousands or millions of years. Ice cores and tree rings are tools to help scientists figure out how the climate has changed in the past.

Ice Cores Ice Core - a tubular sample of ice that shows the layers of snow and ice that have built up over thousands of years literally freezing the events of the past

What types of things do you think get “trapped” in these ice cores?

Ice Cores temperature records atmospheric composition data dust, ash or sediment plant spores bubbles of gas (usually CO 2 ) Pros and Cons?

Ice Cores Extreme Ice National Ice Core Lab ice/videos/national-ice-core-lab t/5

Tree Rings Another tool for studying climate change over the life span of the tree The width of tree rings varies, depending on how much the tree grows in various years Thick ring = good year for growth Thin ring = poor growth, little rainfall Pros and Cons?

Tree Ring Practice B A C D

Lord of the Tree Rings 8E-Gc

Ice Core & Tree Ring Lab Roles Supply Manager – retrieves and returns supplies Reader/Discussion leader – reads the directions and the questions and ensures there is a discussion Scribe – makes sure everyone knows what to write, and is writing Speaker – shares information with the class

Ice Core Lab Send your supply manager to get a piece of paper towel from one of the sinks. Your group will receive 1 ice core sample - peel the paper off and follow the directions! Be sure to answer all of the questions and be ready to share in 5 minutes!

Tree Ring Lab Send your supply manager to your sink and simply set your ice core in the sink to melt – throw away the paper towel! Your group will receive several tree ring samples – read and follow the directions! Be sure to answer all of the questions! After everyone has finished, have your supply manager return ALL tree rings!

Chromebook Login Students Log-In Directions: Username: (first initial of first name + full last name + last 4 of student ID) Password: YYMMDD (birthday) Go To: drive.google.com

Google Doc Directions Once you go to the Google Drive you should already be logged in (your username will be in the upper right corner) On the left – click on “Shared With Me” You should see one document named Ice Cores Vs. Tree Rings (and your block) Click on it to open it

Google Doc Directions Back out of the “Shared Document” On the left hand side, click on “Create” and then choose “Document” Type your response in your own document and then copy and paste it into the class document OR you can share just with me by clicking on “Share” in the upper right and type in my name…SHARE WITH MY CMS.K12.NC.US ADDRESS!

Google Docs Argumentative Writing Prompt Analyze the information you have learned today, and researched about ice cores and tree rings to construct an argumentative paragraph (10 sentences minimum): 1) Opinion/Argument: Which of the two tools is more useful and why – use 3 reasons to support your opinion? 2) Research: Defend your answer using research from 1 cited resource!

Questions??

The Birth of the Earth M8KFIhttp:// M8KFI A great recap as well as a lot we didn’t get a chance to talk about!