M. A. Heinrich 2011
J. L. B. Anderson
Impacts and Extinctions Unit Teacher’s Edition Impacts and Extinctions Frame of Reference This concept is not normally covered in Earth Science material, but would work very well in an integrated Earth Science/ Life Science curriculum. With the separation of Life Science and Earth Science, students have trouble seeing direct connection life has with the history of the Earth. This unit will show how one event has altered the history of life on earth. The unit is designed around the 5e learning cycle. Engage: The students are introduced to a problem with the goal of discovering initial conceptions and generating interest for further study. Explore: The students then collect data using their senses by experimenting and manipulating the variables. Explain: After exploring, the students will then use the data to create usable concepts. They can pool the data into one large data set and then discuss concepts, trends, and explanations in groups. Elaborate: The students then apply their concepts to a new setting. Evaluate: The teacher and students observe and assess the content knowledge and thinking skills that students gained. Learning by inquiry enables students to use critical thinking skills by exploring data and looking for patterns. This method allows the students to better understand the concepts because they evaluate their own initial conceptions and explain patterns they observe. They are allowed to follow the scientific process and make sense of their own data. This learning cycle is discussed further in The BSCS 5E Instructional Model: Origins, Effectiveness, and Applications summary by Rodger W. Bybee et al. Objective Students will improve their understanding of what determines the biologic and geologic effects of an impact, and how to identify the features that are characteristic of impact craters. Skill Level This activity is easily tailored to fit many different student skills. They can look at many different impacts and discuss their results, or take a more in depth approach and research the effects and Page 1 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit conditions of the impact. Impacts affect a variety of topics so students can look into what interests them. Activity Purpose This unit is used to emphasize the information they learned in 7th grade life science in relation to the fragility of life and to expand their limited knowledge on meteorite impacts. They collect data and create conclusions about very important events in the history of the Earth. Prerequisites The students need to have an understanding about what is vital to sustain life on our planet and the varieties of life that currently exist. They should also have a basic understanding of the relationship between drop height and velocity at impact (kinetic energy). Students should have an understanding of how to create their own experiment using one quantitative variable and an ability to graph. Common Misconceptions 
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Meteorites need to be the size of Texas to pose a threat to life forms Meteorite impacts are rare Meteorites remain buried underground at ground zero Everything goes extinct during a mass extinction There has only been one mass extinction Mass extinctions have only one main cause Students Initial Conceptions 
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Students don’t realize the effects that impacts have had on the history of Earth. Students don’t understand the way impacts effect climate and subsequently terrestrial and aquatic species for hundreds of thousands of years. Targeting Students Initial Conceptions To target student’s conceptions about extinctions and impacts, it would be beneficial to first brainstorm as a group what the class already knows and assumes about impact events, extinctions, how often these occur and some of the factors which control them. This list can be referred back to throughout the unit and the students can asses if what they thought at the beginning still holds true. This way the students are convincing themselves that they originally had misconceptions about impacts and extinctions instead of having the teacher tell them they were wrong and providing the correct answer. Sample Schedule Page 2 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Day 1: Teacher demonstration (Engage 1) and preparation for Impact Cratering Lab (Explore 1) Day 2: Impact Cratering lab (Explore 1) data collection Day 3: Data discussion (Explain 1) and comparing to other planets (Elaborate 1) Day 4: Complete any other needed discussion and watch videos frame by frame with guided discussion (Elaborate 1) Day 5: Show students online computer model (Engage 2) then let them follow the worksheet (Explore 2) Day 6: The students reconvene and discuss their findings (Explain 2) and break into groups to discuss the questions (Elaborate 2.) Start discussing extinctions (Engage 3.) Day 7: Using NASA impact info, discuss why we meteorite impacts are not an immediate threat to Earth, how common events are, and further NEO exploration as a class Day 8: Discussion about 5 great extinctions – Possible 6th – what does life need to survive (Explore 3) Day 9: K/T Creature Cards (Explore 3) and Discussion (Explain 3) Day 10: A modern Chicxulub event, Cretaceous Creature Cards (Elaborate 3) Bibliography Alvarez, Walter (1998) T Rex and the Crater of Doom, Vintage Publishers, 208 pgs. Bybee, et al. (2006) The BSCS 5E Instructional Model: Origins, Effectiveness, and Applications. Col, Jeananda. Enchanted Learning. (2010) http://www.enchantedlearning.com/subjects/dinosaurs/plants/Cretaceous.shtml. Retrieved 8 April 2012. Dixon, Dougal. (2007) The World Encyclopedia of Dinosaurs and Prehistoric Creatures, Anness Publishing Ltd, 512 pgs. Guerrero, Angeles Gavira & Frances, Peter. Prehistoric Life (2009) Dorling Kindersley Limited, 512 pgs. Gould, Stephen Jay (2001) The Book of Life, W.W. Norton and Company, 256 pgs. Hallam, Tony (2004) Catastrophes and Lesser Calamities, Oxford Univ. Press, 226 pages. Koeberl, C. & MacLeod, K. (2002) Catastrophic Events and Mass Extinctions: Impacts and Beyond, GSA Special Paper 356, 746 pgs. Mark, Kathleen (1995) Meteorite Craters, Univ. of Arizona Press, 288 pgs. Page 3 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Martin, Anthony J (2001) Introduction to the Study of Dinosaurs, Blackwell Science Inc., 426 pgs. “Mass Extinctions.” Science.NationalGeographic.com. National Geographic, n.d. 14 Aug 2011. Powell, J. L. (1998) Night Comes to the Cretaceous: Dinosaur Extinction and the Transformation of Modern Geology, WH Freeman, 268 pgs Minnesota Academic Science Standards (2009 version) 7.4.3.2.1 – Explain how the fossil record documents the appearance, diversification and extinction of many life forms. Artifact: Foraminifera (i.e.) fossils above and below the KT boundary 7.4.3.2.3‐ Recognize that variation exists in every population and describe how a variation can help or hinder an organism’s ability to survive. Artifact: Different organisms have variations that make them more or less susceptible to survive a meteorite impact, ecology niches 7.4.3.2.4 – Recognize that extinction is a common event and it can occur when the environment changes and a population’s ability to adapt is insufficient to allow its survival. Artifact: Discussion about the 5 mass extinctions and the mechanics of large and small scale extinction 8.1.1.2.1. Use logical reasoning and imagination to develop descriptions, explanations, predictions and models based on evidence. Artifact: Using the creature cards, the students will make a short presentation on what they believe would survive an impact event using the evidences previously presented 8.3.1.2. Landforms are the result of the combination of constructive and destructive processes Artifact: Discussion and lab concerning crater formations Terms and Concepts to be covered: atomic winter, catastrophism, central peak, complex crater, ejecta, ejecta curtain, outer rim, overturned flap, simple crater, tsunami, uniformitarianism, seismic shaking, thermal radiation, airblast, ecological niche Learning Cycle 1: Impact Crater Page 4 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Synopsis (3‐4 50 minute lessons) During this learning cycle, the students explore crater formation and the controls on the final crater dimensions. A video and lab demonstration will be used to make observations and collect data so the students can form connections between projectile variables and crater dimensions. Engage 1: Teacher impact crater demonstration Materials: paint ball gun (magazine fed, not gravity fed), slingshot, projectiles, newspaper, meter sticks, target materials (fine grained sand and coarse grained sand) To engage the students in the lesson the teacher will use a paintball gun (C02 powered paint accelerator) to demonstrate an impact crater to the class. REMINDER: get permission ahead of time from administration to bring a paintball gun to lab. Have a premade target set up prior to class. Fill a shallow container with sand at least 5 cm deep. When the class is ready to begin, without saying anything, use the paintball gun to create an impact in the target material. Questions to pose to the class after the “accelerator impact” (1)
(2)
(3)
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What kind of “event” does this remind you of? What do you notice about the “hole” in the target material? Have they seen anything like this before in pictures or real life? What could you change (variable) to effect how the hole in the ground looks? Explore 1: Impact Crater Lab data collection Adapted from: Impact Cratering: GEOS 105 Activity 7. Anderson, Jennifer L.B.. 2007. Geoscience, Winona State University Materials: Fine grained sand, coarse grained sand, meter sticks, marbles (glass balls), steel balls, wood balls (ball density kit), balls with different diameters but similar mass, clear rulers, Tupperware tubs, newspaper or tarps (cleanup), safety glasses The students will decide what they want to test using a variety of target materials, variations of projectiles, and different conditions of impacts (angle, velocity, etc.). The class will have to decide how they are going to effectively test the variables with the time allotted. It might be important to use a whole class period to introduce the explore phase because if the students do not create a good plan, then they will waste the time in lab getting little accomplished due to poor planning. Together, they need to decide how they are going to measure the diameter of the crater so that their data are Page 5 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit comparable to other lab groups, which group is going to test which variables, and how they are going to reset their target material. Teacher led discussion should involve these points (1) What are we testing? Crater diameter vs velocity? Crater diameter vs mass? Crater diameter vs projectile diameter? (2) How is the diameter of the crater going to be measured? (3) How is the target material going to be reset? (4) How many times will the experiment be repeated? (5) Which groups are going to collect data to answer each question? The students should determine the velocity of the projectile using the energy equations (they can only use this equation to figure out the velocity if they are dropping (releasing) and not throwing the projectile.) Epotential= mgh and Ekinetic= ½ mv2 Epotential= Ekinetic Using algebra they should determine that √(2gh)=v Using g=980 cm/s and h=drop height (cm) they can calculate v During this laboratory, the students should also be keeping careful detailed notes about what they are observing. Instruct them to pay close attention to what the stages are in the crater formation. Wear safety glasses when shooting the paintball gun. Possible lab tests 
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Does the target material effect crater formation? o Flour, fine grained sand, course grained sand, moisture Does the angle of the projectile effect crater formation? o Slingshots Does the speed of the projectile (drop height) effect crater formation? o meter sticks Does the density of the projectile effect crater formation? o Physics ball kit (steel, glass, cork) The data should be recorded in a chart that looks like this Target Material: Coarse Grain Sand Projectile #1: Wooden Ball Crater Height Velocity Diameters (cm) (cm/s) (cm) Average Diameter (cm) Page 6 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit 25 50 75 100 125 150 175 200 221.4 313 383.4 442.7 495 542.2 585.7 626.1 3.75, 3.25, 3.5 4.8, 4.5, 4.3 5.25, 4.5, 4.6 5.25, 5, 5.25 5.5, 5, 5 5.3, 5.25, 5.2 5, 5.5, 5.25 6, 5.5, 5.5 3.5 4.5 4.8 5.2 5.2 5.25 5.25 5.7 Explain 1: Impact Lab Data To explain what they have learned the students should graph their data in their lab notebook to see if there is a correlation with the diameter of the crater and the variable they tested. Example graph of different projectiles in fine grain sand
Average Crater Diameter (cm)
The student’s data should be complied in front of the class as the teacher acts Projectiles in Fine Grain Sand
as a class secretary so the students can 10
discuss in groups which variables effect 8
the crater dimensions. During this 6
discussion the teacher should introduce the vocabulary that is used to define 4
the characteristics of an impact crater. 2
Because they may not see good 0
50
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Drop Height (cm)
development of all the characteristics, the teacher should display real images and detailed drawings of impact craters. The teacher should point out the central peak, ejecta, overturned flap and outer rim. To help illustrate the characteristics, the teacher should use example impact where the students and teacher can point out what they are talking about when naming the features. It may be helpful to use the same target materials the students were using and also using the same set up as was used during the engage section. The students should also discuss how their modifications affected the resulting crater. This would include using a small scale model, the depth of their target materials, impacting at an angle, changing of velocity etc. These are examples of pictures that should be displayed in class: Page 7 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit At this time the students should also discuss the difference between a simple and complex crater and the process of “impact cratering.” Simple: Simple craters are bowl shaped and smaller than complex craters. They to be less than 4km in diameter. tend Complex: Complex craters are over 4km in diameter and have a distinct central The initially steep crater walls have collapsed towards the center. This the crater to be shallower than a simple crater. peak. leads 3 Stages of Crater Formation (1) Compression This is the initial stage during which the projectile (or meteorite) strikes the target surface and transfers its energy and momentum to the target. The meteorite and some of the target are vaporized or melted. A shock wave moves out through the ground surface and backwards through the projectile. (2) Excavation Material is ejected from the growing impact crater and flies through the air as part of the ejecta curtain – the inverted cone of material that marches across the target surface as the crater is forming. The material will be deposited outside of the crater. Page 8 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit (3) Modification This stage ends with the collapse of the newly formed crater. The walls may collapse and the central portion of the crater may rebound upward creating a central peak. Homework: The students will individually create a lab report which includes introduction and results. Elaborate 1: Non‐Vertical Impacts The video series created for this lab is a compilation of three different impact event videos created in a lab setting. Each event is a different impact angle. This shows students the difference in how the impact angle is an important factor in how much target material is disturbed in varying angles. The angles shown in the video series are approximately 90⁰, 45⁰, and 10⁰. The camera zoom is slightly different for each event, but the target material and projectile are the same. The velocities may vary slightly since a sling shot was use as the accelerator, but they are generally comparable. Using the video series, students will be able to predict and observe the differences in projectile angels. Use a video player program where you can use a frame by frame option to slow down and better show the students the angle of the projectile and the subsequent ejecta. Homework: The students will individually be assigned to do 15 minutes of research using the provided websites or their own research from a credible source. They should come prepared to class the next day ready to share something they learned about the Deep Impact mission. 
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http://science.nasa.gov/science‐news/science‐at‐nasa/2010/11jun_missingdebris/ http://www.nasa.gov/mission_pages/deepimpact/main/index.html http://deepimpact.umd.edu/ http://berkeley.edu/news/media/releases/2010/09/10_amateur_astronomers_boli
de.shtml Page 9 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Learning Cycle 2: Local, regional, global effects Synopsis (2‐3 50 minute class periods) Using computer modeling and evidence from other sources, the students will learn about the local, regional, and global effects of an impact event. This will lead into the next cycle pertaining to the effects of life on Earth. Engage 2: Computer Meteorite Impact Model Example Using the(http://impact.ese.ic.ac.uk/ImpactEffectsMap/) website the teacher will map the effects of a meteorite (parameters provided) would hit the classroom. Through this example the students will become initially exposed to the effects of an impact. Use the parameters of the Chicxulub Impact for the engage model: Location of Impact: (Classroom Latitude and Longitude) Projectile Diameter: 17500 m Projectile Density: rock (2700 kg/m3) Impact Velocity: 20 km/s Impact Angle: 45 degrees Target Type: (lithography of school location) Do not show students the other Example crater formed in Winona, MN with effects of the impact that appear http://impact.ese.ic.ac.uk/ImpactEffectsMap/ using the Google Earth image. the same parameters as the Chicxulub event below Page 10 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit This is what appears below the image and will be used in the explore model for data collection: Energy: Energy before atmospheric entry: 1.52 x 1024 Joules = 3.62 x 108 MegaTons TNT 7
The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 2.1 x 10 years Major Global Changes: The Earth is not strongly disturbed by the impact and loses negligible mass. The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis. The impact does not shift the Earth's orbit noticeably. Crater Dimensions: What does this mean? Transient Crater Diameter: 102 km ( = 63.5 miles ) Transient Crater Depth: 36.2 km ( = 22.5 miles ) Final Crater Diameter: 188 km ( = 117 miles ) Final Crater Depth: 1.43 km ( = 0.888 miles ) The crater formed is a complex crater. The volume of the target melted or vaporized is 9530 km3 = 2290 miles3 Roughly half the melt remains in the crater, where its average thickness is 1.16 km ( = 0.72 miles ). Explore 2: Student Model Exploration Start with a discussion and brainstorming activity about what happens to the local region other than just a crater forming. This discussion should include what they learned about ejecta in the previous learning cycle and then expand into what other effects the impact may have. The concepts of airblast, seismic shaking, and thermal radiation should be briefly introduced to and discussed by the students at this time. The vocabulary should not be introduced until they need to give a name to an effect of an impact event. Students will pair up and follow the provided worksheet exploring the effects of an assigned impact with a variety of specifications. (See Student Copy for Worksheet) Each group will use a different historical impact event using their school as ground zero. This will help the students to compare the different size impacts throughout history. The students are also asked to do brief research about their historical impact after completing the worksheet and share this information with the class. Prior to this activity the teacher should identify the latitude and longitude of the school and the area lithography which will be used during the worksheet. Page 11 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit These cards should be distributed to the lab groups. Following the student worksheet they will find facts about their impact using the impact mapping site and other web resources. Meteor Crater (Barringer), USA
Location of Impact: (Classroom Lat & Long) Projectile Diameter: 40m Projectile Density: iron (8000 kg/m3) Impact Velocity: 20 km/s Impact Angle: 45 degrees Target Type: (lithography of school location) Tunguska Fireball, Siberia
Location of Impact: (Classroom Lat & Long) Projectile Diameter: 60 m Projectile Density: rock (2700 kg/m3) Impact Velocity: 20 km/s Impact Angle: 45 degrees Target Type: (lithography of school location) Ries Crater, Germany Location of Impact: (Classroom Lat & Long)Projectile Diameter:1500 m Projectile Density: rock (2700 kg/m3) Impact Velocity: 20 km/s Impact Angle: 30 degrees Target Type: (lithography of school location) Chesapeake Bay, USA
Location of Impact (Classroom Lat & Long) Projectile Diameter: 2300 m Projectile Density: rock (2700 kg/m3) Impact Velocity: 20 km/s Impact Angle: 45 degrees Target Type: (lithography of school location) http://impact.ese.ic.ac.uk/ImpactEffectsMap/ This program maps the effects of an impact crater including airblast, crater, ejecta, seismic shaking and thermal radiation according to the latitude and longitude provided. http://www.purdue.edu/impactearth/ Simulates different impact effects where you can set your own parameters for impact and distance from impact. http://www.unb.ca/fredericton/science/research/passc/ This website has a directory of known impact craters. This information can be used to model impacts on the Purdue website. Explain 2: Post Model Discussion After the students have completed the worksheets in groups, reconvene and discuss the different scenarios the students discovered. Each group should spend some time sharing interesting facts with the class about their historical impact event. Students should further explain the idea of the air blast and the immediate effects of the asteroid. The students should read pgs 9‐11 of T. Rex and the Crater of Doom “The Moment of Impact.” This will serve as a good way to continue discussion about the geologic effects of an impact. This short chapter does a good job breaking down what happens during the beginning of a very large meteorite impact, starting with the compression of the atmosphere. Page 12 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Elaborate 2: Group Questions Present the following questions to the students. They should discuss them in groups and present their thoughts to the class after a short period of time. Q: Why are there more known craters found in some areas of the world than others? (Display the map of all known craters)Where are the most craters found? A: They are found more readily in certain areas because in some countries scientists are hired specifically to look for impact craters. More developed countries are also more likely to have found impact structures on earth because mining the mining research can be used to discover the underground features that define craters. Q: Why doesn’t the Earth’s surface look like the cratered surface of the moon? Page 13 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit A: Earth has active plate tectonics and weathering that destroys and deforms craters. The moon has no atmosphere and no tectonic activity so craters remain until they are filled in by the ejecta of other impacts. Q: On Earth, are older craters found in oceanic or continental crust? A: Continental because ocean crust can only be up to 180 million years old before it is recycled back into the mantle. Continental crust can be billions of years old so it retains craters for a much longer period of time. Page 14 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Learning Cycle 3: Biological Effects and Extinctions Synopsis (2‐3 50 minute class periods) Using the data and concepts they have learned in the previous two learning cycles, the students will come up with the most plausible explanation for why life on Earth suffered during large impact events. They will hypothesize which animals survived the K/T extinction and about who would survive a mass extinction today using creature cards. Engage 3: Extinctions Materials: T. Rex and the Crater of Doom by Walter Alvarez. This is an important resource when teaching about the K/T boundary and is an excellent example of the scientific process. Now that the students have heard about the immediate geologic effects of a meteorite impact, they need to connect that information to long term geologic and biologic effects. Ask the class how much large extinctions have occurred while life has existed on Earth. They may be surprised to hear that there are historically five, and there is evidence to suggest we are in the midst of a sixth extinction. Display this image which depicts extinction rates from the last 600 million years. Since this unit is on impacts and extinctions it is important to address the reason behind all the extinctions but focus on the ONE that has the most evidence for being caused by a meteorite impact. The K/T boundary impact that killed the dinosaurs is the most famous and most likely to capture their attention. Mass Extinction 1: Ordovician The Ordovician-Silurian extinction, about 440 million years ago, involved massive glaciations that locked up much
of the world's water as ice and caused sea levels to drop precipitously. The event took its hardest toll on marine
organisms such as shelled brachiopods, eel-like conodonts, and the trilobites. Mass Extinction 2: Devonian Starting about 360 million years ago, a drawn-out event eliminated about 70 percent of all marine species from Earth
over a span of perhaps 20 million years. Pulses, each lasting 100,000 to 300,000 years, are noted within the larger
late Devonian extinction. Insects, plants, and the first proto-amphibians were on land by then, though the extinctions
dealt landlubbers a severe setback. Mass Extinction 3: Jurassic Page 15 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Massive floods of lava erupting from the central Atlantic magmatic province about 200 million years ago may explain
the Triassic-Jurassic extinction. About 20 percent of all marine families went extinct, as well as most mammal-like
creatures, many large amphibians, and all non-dinosaur archosaurs. An asteroid impact is another possible cause of
the extinction, though a telltale crater has yet to be found. Mass Extinction 4:Permian The Permian-Triassic extinction event about 250 million years ago was the deadliest: More than 90 percent of all
species perished. Many scientists believe an asteroid or comet triggered the massive die-off, but, again, no crater has
been found. Another strong contender is flood volcanism from the Siberian Traps, a large igneous province in Russia.
Impact-triggered volcanism is yet another possibility. Mass Extinction 5:Mesozoic An extraterrestrial impact is most closely linked to the Cretaceous extinction event. A huge crater off Mexico's
Yucatán Peninsula is dated to about 65 million years ago, coinciding with the extinction. Global warming fueled by
volcanic eruptions at the Deccan Flats in India may also have aggravated the event. Whatever the cause, dinosaurs,
as well as about half of all species on the planet, went extinct. Mass Extinction 6?: Cenozoic Today, many scientists think the evidence indicates a sixth mass extinction is under way. The blame for this one,
perhaps the fastest in Earth's history, falls firmly on the shoulders of humans. By the year 2100, human activities such
as pollution, land clearing, and overfishing may have driven more than half of the world's marine and land species to
extinction. Extinction Summaries from: “Mass Extinctions” http://science.nationalgeographic.com/science/prehistoric‐world/mass‐extinction/ Explore 3: Creature Cards Using the information students already know about how life evolves and goes extinct, they will use creature cards to determine what adaptations are best fit for surviving the effects of an impact event. Each creature card describes an animal that was alive prior to the Cretaceous mass extinction. This mass extinction was caused by a variety of factors that scientists still debate today so the students should only be asked to use good evidence to back up why they decide one group of animals survive and another don’t. The goal of this phase is to have the students apply all the concepts they have learned about through the unit as evidence to what survives the K/T extinction. After each group is done they will present to the class what they decided and their reasoning behind it. The teacher should then lead the class in discussion to come up with a class scheme. When Explain 3: Pg 11‐18 of T‐Rex and the Crater of Doom This reading is going to be where it talks about what actually happened to the dinosaurs and the effects it had on them. After the reading the students should discuss what this meant for life at the time. Page 16 of 17 M. A. Heinrich 2011
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Impacts and Extinctions Unit Topics that should be covered: 
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Ejecta Curtain Atomic Winter How mammals survived How marine habitats were effected This should result in discussion about the scientific process that Alvarez went through. Elaborate 3: Creature Cards Now that the students have learned about the effects of the Chixulub impact on life 65 million years ago, it is time for the class to apply what they have learned to what would survive in a modern large scale impact. Using the same process as the Cretaceous Creature Cards, the students will be given Cenozoic Creature Cards. Sample Evaluations (1) Using the teacher demonstration from Engage 1, show the students a premade crater. Have them draw the crater and identify evidence to suggest the angle of impact. (2) If a meteorite 5km in diameter impacted a. New York City what would be the immediate effects on the local GEOLOGY and LIFE? b. The middle of the Pacific Ocean what would be the effects on the local GEOLOGY and LIFE? (3) Describe the parameters of the most destructive type of meteorite impact, discuss the target material, type of meteorite, impact angle, and any other specifications you think are important. (4) Draw the cross section of a complex crater and a simple crater. Label all the features. (5) Given only the angle of impact, have students draw what a cross section of the ejecta plume would look like. Page 17 of 17