Index fossil worksheet answer key

Index fossil worksheet answer key


In addition to this, 24 pages of printable activities and answer keys are included in separate PDF documents. Covers the following skills: Construct a scientific explanation based on evidence from rock strata for how the geologic time scale is used to organize Earth’s 4. There are 13 questions to answer and directions for designing a poster about one of May 22, 2016 · The Fossil Lab Interactive Demo Video: https://goo. This educational module is sponsored by the National Science Foundation. If you don't see any interesting for you, use our search form on bottom ↓ . 7 . Fossils. Answer Key Ch. Answer §. This fossil is. b. Animal dung or scat. Aug 12, 2019 · fossils and relative dating worksheet answer key Relative Time Practical 2. Every fossil tells us something about the age of the rock it's found in, and index fossils are the ones that tell us the most. 3. This impression is a . But for the story to make sense, the clues need to be arranged in order. Jan 22, 2019 · pub cbm index from evolution by natural selection worksheet answer key , source:8bitfiles. 3) Illustrate a Water Cycle Key Station Model MC Answers Station Model Practice 1 Answers Station Model Practice 2 Answers Test Review Answers NY Tornado Answers Dew Point Temp Key RH and DewPoint Key Wind Belts and Clouds M. 2) Explain carrying capacity. (Explore). The first answer I get from the Feb 20, 2015 · A printable fossil word search containing 18 words. 7in Punchline Algebra book A 12. Comparative Anatomy Worksheet Answer Key Pdf. Discuss how the fossil record supports the biblical account of God’s mercy on His creation. Describe how a mold is related to a cast. Includes Preparation, Procedure, Resources Oct 06, 2019 · Some of the worksheets below are Dimensional Analysis Practice Worksheets with Answers, Using the factor label method and train track method to solve several interesting dimensional analysis problems, multiple choice questions with fun word problems. Students answer the question: What is a fossil? By: • Being paleontologists as they gather data observing, drawing, labeling, and describing various fossils as they rotate through fossil stations. Uniformitarianism. . List the two techniques paleontologists use to determine the age of fossils. Evidence Chart Key Evidence What it tells us: Past Lives 1. Most commonly, soft organic parts decompose while hard body parts, such as bones, teeth, shells and exoskeletons, are chemically dissolved and mineralized () into rock. Scientists use the fossils around the new fossil to compare to known fossils. This makes a great homework sheet or in-class review. Blackline Master 6: Layers & Laws Check for Understanding. This worksheet has 13 Earth Science Regents questions about index fossils. Engage: Who Dunit? Purpose: In this lecture, students will learn the origins and applications of each of the three fossil fuels, including coal, crude oil, and natural gas. 1. 1) Define ecosystem. Specific issues covered include surface and subsurface coal mining, oil drilling and spills, and the debate over hydraulic fracturing. Geologists can use fossils and relative dating worksheet answers Quiz & Worksheet - Relative Dating with Worksheet. No other additional credit is available. Radioactivity worksheet answer key, or answers relative dating worksheet key middle school september 8. If this "Fossil Find" scenario is typical of the work of scientists, what features of the nature of science does it demonstrate? ANS. Geologists were able to use the faunal succession of fossil assemblages to correlate distant rock beds to each other. 13. Some pages may require you to click on an image or answer a question before the link appears to guide you to the next page. Geologists have come up with a geological time scale, which divides the history of Earth into eons. 41 - Index Fossil Key in your textbook, identify which Grand Canyon fossils are index fossils Go over answers Now do Bryce Canyon and Zion National Park! Work with a partner and record answers on bottom of WS or on scratch piece of paper [Note: For embedded comments, checks for understanding (CFUs), and key additional information on transitions and key parts of the lesson not necessarily included in the below narrative, please go to the comments in the following document: Index Fossils & Correlation (Whole Lesson w/comments). index fossil: a fossil of a species that was abundant, existed briefly, and was widespread geographically • Organisms that became index fossils lived only during a specific time. When reading Earth history, these layers would be “read” from bottom to top, or oldest to most recent. The ammonite Tropites is an index fossil. The PDF resources below are password protected. Emphasize that they must t This Layers and Laws: The Law of Superposition and Index Fossils Lesson Plan is suitable for 6th - 8th Grade. Our understanding of the answer to help you ever wondered how science relative dating the biologics compliance assistant. fossil and get familiar with each fossil’s characteristics. I often used this as a culminating activity for my Geo. Explain how index fossils may be used to correlate rock strata from . Answer Key. Name: _____ __C__ 7. Learn vocabulary, terms, and more with flashcards, games, and other study tools. What do geologists use the fossil record worksheet answers. The relative age of rocks worksheet answers. 27 Jan 2011 Extensive fossil graveyards and coal deposits are more consistent with a The answer is that in general, the lower layers record the organisms that . pdf FREE PDF DOWNLOAD Fossil Record - The Biology Corner hmxearthscience. Were taken from the same dig site. Answer the following questions on a separate sheet of paper. Add your own words A worksheet is a question sheet that you are given to work out the answers. Index fossils act has MARKERS for the time organisms were alive on Earth. Layers and Laws Student Activity Sheet – Answer Key. • Gather data using a science journal or the attached worksheet. 4) In what kinds of rocks might you find the fossils from this activity? 5) State the Law of Superposition and explain how this activity illustrates this law. Then have the students place the fossils on one student’s labsheets, matching fossils to illustrations on the labsheet/ 4. 6 – Infer the relative age of rocks and fossils from index fossils and the ordering of the rock layers. examples show one way of setting out your answers to geological history. Leaf. Relative and Absolute Ages. Both columns. 87. Tools. Blackline Master 6 – Answer Keys. How Fossils Are Made: This one page handout explains how fossils are made and the kinds of fossils paleontologists study. In other words, processes that we observe today— such as erosion and deposition—remain uniform, or do not Dec 19, 2015 · On this page you can read or download chapter 19 lab using index fossils worksheet in PDF format. And I’m sure middle school students would, too! I’ve seen it all over the Internet and had a copy 20 years ago so I have no idea who the actual image of the bones belongs to. pdf FREE PDF DOWNLOAD NOW!!! Source #2: the fossil record worksheet answers. Most geologists are trained to think that the present is the key to the past  Relative Dating Worksheet . Therefore, rocks that contain Phacops fossils are probably about 400 million years old. Adjust if necessary. Index fossils (also called key fossils or type fossils) are those that are used to define periods of geologic time. Once they have an okay from you, they need to use the Fossil Key to identify each Relative fossil dating worksheet. An editable Word document is included. 5-6. F. Click here to print this answer key! Click here to save or print this answer key as a PDF! Dec 19, 2015 · On this page you can read or download chapter 19 lab using index fossils lab answer key in PDF format. 2 Fossils: Evidence of Past Life Reading Strategy Monitoring Your Understanding Draw and complete a chart like the one below. The processes occurring in fossils. Relative age dating worksheet answer key. In a ddition, Radiometric dating worksheet answer key - Join the leader in online dating services and find a date today. There is no . Right? The Links Are Missing (from Refuting Evolution) The Fossil Record: Becoming More Random All the Time; Where are all the human fossils? Living fossils: a powerful argument for creation Fossil Record Handout. Assist students as needed during game play, pause playlist if you need to address content or questions to entire class. fossils and relative dating worksheet answers Quiz & Worksheet - Relative Dating with Worksheet. Key Relationships Key Air Masses and Fronts Key Air Mass Questions Key Fronts Short Answer KEY-----Sequence of Events - Key Index About This Quiz & Worksheet. Chapter 5 Project Worksheet 2 (p. Students will be able to infer the relative age of rocks and fossils from index fossils and the ordering of the rock layers. Key articles. Biology relative dating worksheet answer key Look check this out some geologic strata on several topics including relative dating, absolute dating, and fossils. Index fossils can also be used to date rocks in separate areas. 4. A fossil is a fossil is a Do fossils give evidence of their quick formation during great catastrophe, such as Noah's Flood? Index fossils— really? Index: Mass extinctions and fossils | The fossilisation process | Blast from the past | Geological time Download all FET Grade 10-12 Worksheets (zip 5. A volcanic  Check out our new Printable Worksheet and Game Generator! This website Print Answer Key (Only the test content will print). Claims million years. A plant. Phacops lived about 400 million years ago. Equences of rock record. Relative age of rocks. Alternative fossil sheet (Pakicetus) for cutting apart. 3 Multiple Choice. . Intended Student Learning. Layers of Rock. Plaatje. Dig Site 1 Rock/Sediment Layer Name of Fossils Found (at least 2 in layers 1 and 3) Below are some reasonable answers to the last few questions on the worksheet: 6. Or enc one letter that indicates a time for which there is no rock record in New York State. doc), PDF File (. Learn. Quizlet provides relative age rocks activity consists age tests are on index fossils. Explain how the principle of uniformitarianism is used to interpret Earth’s past. Natural selection can’t generate brand new genetic details. Students from 9th - 12th loved it. See how well you can answer multiple-choice questions on topics like how the principle of fossil succession applies to dating and  Blackline Master 5: Superposition Answer Guide for Fossil Cards. Geologic time, history, and changing life forms are indicated by fossils and successive sedimentation, folding, faulting . Reference Collection of Fossils (Worksheet 1) . Range °hall of Fossil  Cover the hole with an aluminium sheet (not foil) that has a 1 mm hole in its centre. To be useful as an   6 Apr 2015 Standard 8-2. This concept is termed faunal succession. Which two layers are of approximately the same age? Quiz & Worksheet - Relative Dating with Index Worksheet. Columns I and II contain rock layers A, B, C and D, E, F. com makes it easy to get the grade you want! Finding Clues to Rock Layers Fossil clues give geologists a good idea of what life on Earth was like millions or even billions of years ago. This quiz and worksheet will help you evaluate your knowledge of how radiometric dating and index fossils are used in analyzing types of rocks. A fossil is a fossil is a fossil. Because it lived for such a short time, it is a good index fossil. Topics covered: Geologists can answer a relative age dating. After you read this section, you should be able to answer . (Engage). 6-billion-year-old history. Letter a indicates a specific time during which geologic period? the mountain building event (orogeny) that was occurring in eastern North America at the time represented by letter g. Closure:. Bird. Geologic Dating Answer Key. What is an important characteristic of an index fossil-? What is the answer to page 3. South Carolina Standards. 2. Fossil A is found in a layer of rock above a layer containing Fossil B. Using the diagram below, which of the following . 7. 9. Layers of sedimentary rocks show relative age. 7in BECOMING WHALES INDEX TO PDF TEXT FILES, TIMELINES and TABLES to print out and copy for classroom use [To get the FREE Adobe Acrobat Reader, see insturctions at bottom of this page] BECOMING WHALES: the main body of this lesson (10 pages) as displayed on the website, for easy printout for teacher use. See how well you can answer multiple-choice questions on topics like how the principle of fossil succession applies to dating and how to By correlating fossils from various parts of the world, scientists are able to give relative ages to particular strata. For the questions below, circle the correct answer. What can layers of rock teach us about the climate? Young scientists solve a mystery about who stole a cookie by applying the law of superposition. Widespread = The fossil must show up in each of the different outcrops (columns). Second, cut apart the bones on the fossil sheet. There are both multiple choice and short answer questions. On-line K-12 educational resource. Science Worksheets and Study Guides High School. This relative ages of rocks worksheet is suitable for 7th 12th grade. It is a: a) Trace fossil b) Body fossil. To know: Vital records around the earth science 10 unit. 5. Study Flashcards On Science Chapter 4: A Trip Through Geologic Time Key Terms at Cram. About This Quiz & Worksheet. Tropites lived from between 230 million and 208 million years ago. • How index fossils are used to determine the ages of rock layers • How the absolute ages of rocks are determined KEY CONCEPT Rocks provide a timeline for Earth. Using the information you’ve learned so far and in the “Application” section of this book, plan a trip to a nearby cliff, cut, creek, or quarry to hunt for fossils. In addition to Index fossils and similar rocks types help geologists establish correlations. NGSS MS LS2-1 Ecosystems: Resource Availability Worksheet with Answer KeyWorksheet to check for key understanding of subject matter. Principles of rocks they relative dating. VOCABULARY relative dating isotope radiometric dating half-life MAIN IDEA: Fossils can form in several ways. The fossil might be able to be used as an index fossil. The relative age of rocks  16 Jul 2012 A key bed can be used like an index fossil since a key bed is a distinctive layer of rock that can be recognized across a large area. Fossils are clues in the story of Earth’s past. page 8 – WS – DGE – U1 Book reference: Short Answer. 88. Join and search! Is the number one destination for online dating with more marriages than any other dating or personals site. Start studying Science Fusion, grade 5, Unit 10, Fossils. pdf (Practice worksheet for identifying dependent and independent variables) http://www. Within a fossil. the contents of fossil nests Some dinosaurs cared for their young while Fossil Exercise Answer Sheet Name_ ____ Part A "Getting into the Fossil Record". Topics  2 Nov 2019 Correlating Rock Layers Using Index Fossils Worksheet November 2 - Free download as Word Doc (. Time to find some Index Fossils! Using p. e. Blackline Master 7: Answer Keys. index fossils, relative and absolute dating, the geologic time scale, and major dents to refer to Sections 4 and 5 while answer- fied in the key. its uncertainty, and that teamwork is more efficient. Because of this, scientists can estimate the ages of rock layers based on the index fossils they contain. Yes, if the faults contained fossils, particularly index fossils. the appearance of the same index fossil in rock of different areas sows that the rock layers formed at about the same time. Easily Recognizable is usually not an issue in these problems because the diagram clearly illustrates each fossil. Fossil: The remains of any past life form that has died and been preserved in the rock record. Questions: Why is the layer with index fossil T missing in outcrop 1? What are some of the characteristics of a volcanic ash deposit that makes it an excellent geologic time marker? Correlate the rock layers found below using the index fossils. Procedure Study the rock layers at Sites 1 and 2. This helps us reconstruct how the strata was deposited in the past. This station has VIDEO WORKSHEET – BILL NYE THE SCIENCE GUY (FOSSILS) Question Answer What are fossils? What kinds of materials can preserve fossils and organism remains? “Fossil” comes from the old Latin word that means what? What evidence do we have that the Earth has changed a lot? What percent of once-living organisms are now gone? Where are the La Index fossils are fossils that are preserved in the rock record of the Earth and are specifically found in a particular time period or environment. Key Ideas. Mimicry and explorations red math mates answer sugar mummy dating site in kenya 40 earth or lab groups, the. Activities 1. What does the fossil record reveal about the evolution of life List the index fossils and the ash deposit from oldest to youngest. were taken from the same dig site. that are used as index fossils. Reconstruct the complete sequence of events and draw the layers (with the fossils if The Great Fossil Find - Working as a Paleontologist process to explore how paleontologists solve problems and answer questions about the natural world This worksheet has 13 Earth Science Regents questions about index fossils. Chapter 19: The History of Life Section: 19. 8. Our stratigraphic methods. FOSSIL QUEST A. ntifying%20variables. The same processes that create the rocks today were in operation in the past. THE USE OF FOSSILS - DATING Fossils have been used to date rocks as they are time markers – many species lived at a particular time and later became extinct. Geologic Time Worksheet Go to the following URL: answer the questions on this sheet at the Fossil Name Relative Time Unique Fact . 6Mb)  You can watch the video on index fossils posted under resources to get an idea material at the end of this worksheet) Figure 1: Fossils and the geologic time scale to youngest on a separate sheet of paper before you answer the questions. Types of 3 of science Chapter 12 - Clues to Earth's Past. fossils (A, B or C ) is the oldest? Examine the following diagrams. May 19, 2019 · geologic time scale worksheet answer key scribd the geologic time scale is used as a record of the major events and diversity of life forms present in earth’s history with this information 2 3 scientists first developed the geologic time scale by studying rock layers and index fossils worldwide the geological time scale marden senior college Jane carefully removed the fossil from the rocks and donated them to a museum. Fossils are the remains or evidence of prehistoric plants and animals that have been preserved in rock. using index fossils lab answer key is available in our digital library an online access to it is set as public so you can get it instantly. McKinney VOCABULARY Aboslute age dating Fossil Geologists Half-life Relative age dating HELPFUL TERMS Paleontologists Isotope Radioactive decay Determining the Age of Rocks and Fossils 1 New York State Standards 1 Inside This Packet New York State Standards Middle School Activity Standard 1 New York Science Teacher is your home for science labs, demonstrations, lesson plans, activities, worksheets, notes, regents review material, educational related information & more! Fossils. Quizlet flashcards activities and games help you improve your grades. Key Concepts What are fossils? What determines if an organism will become a fossil? What is the principle of fossil succession? Vocabulary fossil index 2) Which fossil organisms could possibly be used as index fossils? 3) Name three organisms represented that probably could not be used as index fossils and explain why. is the age EDUCATOR’S RESOURCE PACK C West Coast Fossil Park 4. Can be edited for younger or older students. The Mystery Fossil Bones Activity This was one of my favorites. Determining the Age of Rocks and Fossils By: Frank K. Dating the fossil record worksheet Fossils occurred higher stratigraphically this manner. Click the links at the bottom of the page to continue through the site. Most of-ten, the hard, durable body parts such as bones, teeth, or shells are preserved. Circle the correct answers in A and B. Fossils Worksheet – Earth Science. Answers to activity: Part 1: 1. J. Fossil Worksheets For 5th Grade | worksheet example worksheet Index Fossils Worksheet climate test questions index of wp content uploads sites 259 2010 11 . Scientists ask other scientists to date the fossils based on known information. Yes, this . Simpsons Scientific Method-key. These fossils are also called, guide fossils. com Worksheet: What are fossils? The word ‘fossil’ is from the Latin word “fossilis” meaning ‘to dig’. Cram. The preserved fossil remains may later be Xtension of dating. clemson. Answer the questions on your worksheet. An animal bone. These rock layers fossils, called index fossils, help geologists match rock layers. A Trip Through Geologic Time Fossils Understanding Main Ideas Fill in the blanks in the table below. The Present Is the Key to the Past In 1795, two years before he died, James Hutton collected his notes and wrote Theory of the Earth. 10. Science Worksheets and Study Guides Eighth Grade. pdf), Text File (. Science Pictures and a Multiplication Freebie (Ashleigh's gives you fact sheets on some ofthe important animals and plants in the fossil record so that you will be able to talk to your students with confidence about fossils. In the spaces provided, write either the type of fossil being described or a brief description of how the fossil type is formed. 1 The Fossil Record An index fossil is a species that is recognizable to answer that question by simulating What is an index fossil? What do index fossils reveal about other material found with them? 8. There are a lot of means. What can a paleontologist tell from fossil footprints of a dinosaur? 9. Relative age does not tell the exact age of an object. Write down your observations and answer the questions on the following the same age in different areas and is referred to as a guide or index fossil. C. Answer the following questions. The password to access the protected tests and answer keys is: ReadersProtect 7th Grade Science Evolution Unit Information Milestones Domain/Weight: Evolution 15% Purpose/Goal(s): Within the Evolution domain, students are expected to understand how traits change over time, and how this affects adaptation and survival of a species. ? Sheet a (PARTS A . Stable and worksheet key videos an organism lived in geologic time practical. Sw science is the principles to maintain normal activity to date rocks worksheet lab worksheet answer key. Such index fossils must be distinctive, globally distributed, and occupy a short time range to be useful. Fossils of dinosaurs have been found in many places on Earth. Students complete the left side to the worksheet (see resources below), giving their best answers or guesses. Merely said, the using index fossils lab answer key is Fossil Gap Worksheet Answer Key Time Period Years Ago Fossil Rockhillian (youngest) 10,000 Upper Lower Students should draw a fossil here Florencian 1. Activity Relative Age, Rock Layers, and Index Fossils Problem: How do we date Share this sheet with your group of four Fossils Worksheet – Earth Science. What can the index fossils tell you about the organisms in the layers of rock with them, above them, or below them? _____ Three pages of intriguing pictures and reading passages about the natural history of Africa's West Coast Fossil Park make up the bulk of this handout. Geologists are able to reconstruct the sequence of events that has shaped the Earth’s surface from the study of petrology, stratigraphy and palaeontology. • Another way to estimate when rocks formed is done by comparing time spans in which more than one fossil appears. glencoe. com. Clues to Earth’s Past 13 Name Date Class LaboratoryActivity Hands-On Activities 2 Index Fossils Fossils found in the deepest layer of undisturbed rocks in an area represent the oldest forms of life in that particular rock formation. 4 pages. html (Rules for graphing) answer key). Suppose the principles of 3 half-lives of principles of key. These pages incorporate a. Jun 26, 2017 · Ashfall Fossil Beds - Wikipedia The site is now protected as Ashfall Fossil Beds State Historical Park, which includes a visitor center with interpretive displays and working fossil preparation laboratory, Newly uncovered fossils are being left exactly as they are found: THE FOSSIL RECORD Study Guide KEY CONCEPT Fossils are a record of life that existed in the past. Fossils Questions and Answers Key articles. Behavior is early s and artifacts are two basic approaches: What i see often but have never and spoken to know the dating. Scientists compare the new fossil directly to known fossils to find its age. The following website has more information on stratigraphy and the scientists involved in changing how we think: Instructions: Use this answer sheet to identify the objects at each of the stations. For Holt, pages 178-179 of Chapter 8 Evolution and page 202 of Chapter 9 History of Life. Find index fossil lesson plans and teaching resources. Our books collection saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. edu/ces/phoenix/tutorials/graph/index. History Unit. Walk around and check to be sure they are right. This game will help test their knowledge. 8 million Upper Lower Students should draw a fossil here Greenvillian 24 million Upper Lower Please keep in mind that the name and dates of this timeline are fictional for use with this activity. 47'. the entire class to all of the physical properties; refer to the student worksheet to . and B). A biology resource site for teachers and students which includes lesson plans, student handouts, powerpoint presentations and laboratory investigations. txt) or view Explain how you got your answer. Which fossil is probably older? Explain your answer. Write down the similarities and differences between the layers at the two sites. growth rings in fossil trees or shells Growth rings tell us the number of years that individual lived. net. gl/Da8eFr The Fossil Lab is a 119 page hyperlinked PDF document that guides students through the investigation of 33 important index fossils. Define fossils worksheet answer key point: Girls for esl teachers. remains of organisms in the sediment may become fossils. Each question is for the station of the same letter. Eachfact sheet contains a description ofthe organismto aid inidentification, information on when, where Students read textbook sections on fossils. This type Stratigraphy is built on the concept that the present is the key to understanding the past. If students finish the first game and worksheet early they can continue on in the playlist and try the game L ayard History - Through Rocks and Time . For station C, fill in the blanks with the correct answer. later in time) than the abundance of reptile fossils. pdf - NPAScienceDepartment. Comparative Anatomy Worksheet Answer Key Pdf > http://urlin. Not designed as a project to design or construct a model. How would a geologist use the principle of superposition to determine the relative ages of the rocks of the Grand Canyon? Section 21. See how well you can answer multiple-choice questions on topics like how the principle of fossil succession applies to dating and how FOSSIL? When choosing the right index fossil we can reinterpret the characteristics of index fossils to help us: 1. com ample of an index fossil. Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation. 6 (INDEX FOSSILS & CORRELATION [LAB]) • HISTORY OF THE EARTH Regents Earth Science 9TH GRADE 5 Procedure B: The second set of diagrams identifies four types of index fossils and shows two columns of fossil bearing rock strata. The is the age superposition; index fossils; uniformitarianism; unconformities. Circle the correct answer! This fossil is: - a plant - an animal bone - animal dung or scat Oct 15, 2011 · to toggle between the values version and the formulas version of a worksheet hold down the key What is an important characteristic of an index fossil-? What is the answer to page 3. curled up fossil trilobites Trilobites may have curled up to avoid predation just as pill bugs do today. READING CHECK 9. In that series of books, he stated that the key to understanding Earth’s history was all around us. species are index fossils . Index fossils are fossils that are known to only  Key Takeaways Fossils are important evidence for evolution because they show that life on earth was once different from life found on . Quickly memorize the terms, phrases and much more. However, To preview this answer key, click on the File menu and select Print Preview. Name _____ Date _____ Per ____ Virtual Lab: Fossil Data Data Table: You may need to hit the refresh button in Internet Explorer several times to get the other dig sites to work and load properly. Fish. From index fossils geologic time worksheets to index fossils and trilobites videos, quickly find teacher-reviewed educational resources. Fossil Worksheets and Teaching Resources . Relative age means the age of one object compared to the age of another object. At station D, draw a picture of your favorite fossil. After you finish this section, correct or add details as needed. For example, geologists noticed that the abundance of mammal fossils occurred higher stratigraphically (i. us/2fr68 AP®EnvironmentalScience-APCentral The Fossil Book study guide • 27 . Which two layers are of approximately the same age? coral index fossil Lichenaria shown above existed on Earth. most recent on the Report Sheet. principle of superposition and you will see that the only possible answer to this puzzle is that layer A is the Key to Rock Symbols. index fossil worksheet answer key