This is the Earth and Life Science Quarter 1 Module 12 self-learning module, Relative and Absolute Dating, for Senior High School learners. It was produced by DepEd Region 4A CALABARZON under the Alternative Delivery Mode. After working through it, learners should be able to tell relative dating apart from absolute dating and explain how geologists find the age of rock layers.
On this page 6 sections
What learners will learn
The module covers one lesson, Lesson 1: Relative and Absolute Dating. By the end of it, learners are expected to:
- differentiate relative from absolute dating through pictures presented; and
- compare relative and absolute dating using a comparison chart.
Relative dating: putting rocks in order
Geologic time is measured in two ways. Relative age gives only the order in which events happened. Absolute age is age in years. It tells both the order of events and how much time has passed since they happened.
Before absolute age could be measured, geologists worked out relative ages from field observations. They used these principles:
- Original horizontality: sediment usually builds up in horizontal layers. If layers are tilted or folded, tectonic forces moved them after they formed.
- Superposition: sedimentary rocks get younger from bottom to top, because new layers pile up on top. In an undisturbed stack, the bottom layer is the oldest and the top layer is the youngest.
- Crosscutting relationships: rocks must exist before something cuts through them, such as an intrusion or a dike. The layers that are cut are older than the rock that cuts across them.
- Faunal succession: living species followed one another in a definite, recognizable order. Because of this, the fossils in sedimentary rock show its relative age.
- Lateral continuity: layers of sediment are continuous. Matching layers on either side of a valley or eroded area were once one connected layer.
Absolute dating: finding the age in years
To find an exact age, scientists use a natural process that runs at a constant rate: the radioactive decay of elements in rocks. Radioactive elements have unstable isotopes that break down on their own. The original element is the parent isotope, and what it becomes is the daughter isotope. For example, a form of uranium (U) decays into lead (Pb).
The longer a rock exists, the more daughter isotopes build up in it. Measuring the amounts of parent and daughter isotopes to find a rock’s age is called radioactive dating. It works because decay goes on at a constant rate, whatever the temperature, pressure, or chemical surroundings.
The module lists these commonly used isotopes:
| Parent isotope | Daughter isotope | Half-life (years) | Effective dating range (years) | Materials dated |
|---|---|---|---|---|
| Carbon-14 | Nitrogen-14 | 5,730 | 100 to 50,000 | Wood, shells, anything once alive, trapped carbon dioxide |
| Potassium-40 | Argon-40, Calcium-40 | 1.3 billion | 40,000 to 4.6 billion | Muscovite, biotite, volcanic rock |
| Uranium-238 | Lead-206 | 4.5 billion | 10 million to 4.6 billion | Zircon |
| Uranium-235 | Lead-207 | 710 million | 10 million to 4.6 billion | Uraninite |
Half-life
The half-life is the time it takes for half of the original parent atoms to decay. Each decay process has its own half-life. The module gives this example: if an igneous rock held 1,000 atoms of U-235 when it solidified, then after about 713 million years it would hold 500 atoms of U-235 and 500 atoms of the daughter element, Pb-207. The ratio of parent atoms to daughter atoms tells how long ago the rock solidified.
Relative and absolute dating compared
| Relative dating | Absolute dating |
|---|---|
| Arranges geological events, and the rocks they leave behind, in sequence | Gives rocks an actual date or date range, in number of years |
| Qualitative method | Quantitative method (also called numerical dating) |
| Uses the stratigraphy method: oldest at the bottom, youngest at the top | Uses the radiometric method: isotopes and half-life |
How to use this module
The module follows the usual self-learning module parts:
- What I Know: a 15-item multiple-choice pretest that checks what you already know.
- What’s In: Activity 1, a word puzzle (rock, relative, absolute, earth, age). You then define the words, write sentences with them, and explain how absolute age differs from relative age.
- What’s New: Activity 2, guide questions about a diagram of limestone, shale, sandstone, and granite layers.
- What is It: the discussion, plus Activity 3. In Part A you list lettered rock layers from youngest to oldest. In Part B you read ages in millions of years from a diagram of layers with fossils.
- What’s More: Activity 4, a concept map, and Activity 5, a fill-in-the-missing-letters exercise on key terms.
- What I Have Learned: fill-in-the-blank sentences using a word pool.
- What I Can Do: a Venn diagram comparing absolute and relative dating.
- Assessment: a 15-item posttest, followed by an additional activity where you choose a dating method and justify your choice.
For learners: Write all answers on a separate sheet of paper and do not mark the module. Answer keys are at the end; use them honestly, only after you finish each part.
For parents: Help your child follow the parts in order. Contact the teacher if your child has trouble with a task.
For teachers: The Notes to the Teacher ask you to discuss the simple dating principles, in any mode, before learners move on to the next activity.
Frequently asked questions
What grade level is this Earth and Life Science module for?
It is a Senior High School module for the Earth and Life Science subject, Quarter 1, Module 12. The module does not name a specific grade.
What is the difference between relative and absolute dating?
Relative dating puts rocks and geological events in order using principles such as superposition, but it gives no number of years. Absolute dating gives an actual age or age range in years using radioactive decay and half-life.
What are the principles of relative dating in this module?
The module discusses five: original horizontality, superposition, crosscutting relationships, faunal succession, and lateral continuity.
What is half-life?
Half-life is the time it takes for half of the original parent atoms in a radioactive decay process to decay. Each decay process has its own half-life, such as 5,730 years for carbon-14.
Does the module have an answer key?
Yes. The module has answer keys for the pretest, the activities, and the assessment.
Full text of the module
The text below is a transcription of the PDF above, as printed.
Earth and Life Science Quarter 1 – Module 12: Relative and Absolute Dating
Senior High School
[illustration: students reading and studying outdoors and at a desk, with a teacher, a student beside a globe, and a child working by a lamp]
Earth and Life Science Alternative Delivery Mode Quarter 1 – Module 10: Movements of Plates and Formation of Folds and Faults First Edition, 2021
Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties.
Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this module are owned by their respective copyright holders. Every effort has been exerted to locate and seek permission to use these materials from their respective copyright owners. The publisher and authors do not represent nor claim ownership over them.
Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio
Printed in the Philippines by ________________________
Development Team of the Module
Writer: Chris B. De Jesus
Editors: Erwin R. Abrencillo, Jocelyn M. Manset
Reviewers: Dominic P. Almirez, Franz Kevin Manalo, Princess Paolah L. De Guzman, Marissa C. Betchaida, Louie L. Alvarez, Gregorio M. De Chavez, Jr., Jocelyn M. Manset, Mario B. Maramot, Elaine T. Balaogan, Job S. Zape Jr., Avelyn A. Cajayon, Victoria M. Magpantay, Fernando M. Villanueva
Illustrator: Ednelinda Robles, Cherry Amor Laroza, Lovely Joy La Rosa, Charles Erick A. Jusay, Sandro Carlo B. Tablizo
Layout Artist: Elizalde L. Piol, Anselma M. Ebero, Jocelyn M. Manset
Management Team: Wilfredo E. Cabral, Job S. Zape Jr., Eugenio S. Adrao, Elaine T. Balaogan, Merthel M. Evardome, Nadine C. Celindro, Nicolas M. Burgos, Mario B. Maramot, Fe M. Ong-ongowan, Rosalinda A. Mendoza
Department of Education – Region 4A CALABARZON
Office Address: Gate 2 Karangalan Village, Brgy. San Isidro, Cainta, Rizal Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: lrmd.calabarzon@deped.gov.ph
Earth and Life Science
Quarter 1 – Module 12: Relative and Absolute Dating
Senior High School
Introductory Message
This Self-Learning Module (SLM) is prepared so that you, our dear learners, can continue your studies and learn while at home. Activities, questions, directions, exercises, and discussions are carefully stated for you to understand each lesson.
Each SLM is composed of different parts. Each part shall guide you step-by-step as you discover and understand the lesson prepared for you.
Pre-tests are provided to measure your prior knowledge on lessons in each SLM. This will tell you if you need to proceed on completing this module or if you need to ask your facilitator or your teacher’s assistance for better understanding of the lesson. At the end of each module, you need to answer the post-test to self-check you’re learning. Answer keys are provided for each activity and test. We trust that you will be honest in using these.
In addition to the material in the main text, Notes to the Teacher are also provided to our facilitators and parents for strategies and reminders on how they can best help you on your home-based learning.
Please use this module with care. Do not put unnecessary marks on any part of this SLM. Use a separate sheet of paper in answering the exercises and tests. And read the instructions carefully before performing each task.
If you have any questions in using this SLM or any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator.
Thank you.
What I Need to Know
This module was designed and written with you in mind. It is here to help you master the different methods in determining the age of stratified rocks. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.
The module covers:
- Lesson 1 – Relative and Absolute Dating
After going through this module, you are expected to:
- differentiate relative from absolute dating through pictures presented; and
- compare relative and absolute dating using comparison chart.
What I Know
Directions. Read the following questions and choose the letter of the correct answer. Write the chosen letter on a separate sheet of paper.
Which of these is the best indication of the relative age of a rock layer?
A. the thickness of the layer
B. the chemical make-up of the layer
C. the distance of the layer on the surface
D. the position of the layer compared to other layersWhich of the following processes will give the relative age of a rock?
A. examining the environment in which the rock is found
B. examining the rock’s relative position in a rock outcrop
C. comparing the amount of decayed and undecayed radioactive isotopes
D. comparing the size of crystals in the upper and lower parts of the rockWhere can you find the oldest rock in an undisturbed rock file?
A. on the topmost
B. at the bottom
C. upper part
D. lower partThe principle of horizontality is based on the observation that sediment usually accumulates in layers. How will you describe the rock layering based on this principle?
A. Rocks are pile horizontally with the oldest at the bottom and youngest on the topmost.
B. Rocks are pile horizontally with the oldest on the topmost and youngest at the bottom.
C. Rocks are in inclined layers, the steeper the tiltation the older the rock is.
D. Rocks are piled in any form, the darker the rock the older it is.Which of the following makes use of the position of rocks to determine its age?
A. Absolute Dating
B. Radioactive Dating
C. Radiometric Dating
D. Relative DatingWhich type of dating method can be used on rock layers by applying the Law of Superposition?
A. Absolute Dating
B. Radioactive Dating
C. Radiometric Dating
D. Relative DatingWhich was the first method used to determine ages of rock and fossils?
A. Relative Dating
B. Absolute Dating
C. Radioactive Dating
D. Radiometric DatingWhat is the difference between an absolute date and a relative date?
A. An absolute date refers to a year or a range of years while a relative date indicates a chronological order.
B. A relative date is derived from radiometric dating techniques while an absolute date comes from guesswork.
C. A relative date refers to a year or a range of years while an absolute date indicates a chronological order.
D. An absolute date involves testing of sedimentary rocks while relative date involves testing of igneous rocks.
Refer to the diagram below and answer the questions that follow.
[chart: diagram; untitled geological cross-section showing rock layers numbered 1, 3, 4, 5, and 6 (layer 6 appears twice), with a V-shaped valley, an igneous intrusion, and points marked A and B]
Which layer of the rocks follows the principle of superposition?
A. Layer 1
B. Layer 3
C. Layer 4
D. Layer 6Which layer of the rocks shows the cross-cutting relationship?
A. Layer 1
B. Layer 3
C. Layer 4
D. Layer 6What method of Rock Dating is used in giving rocks an actual date?
A. Absolute Dating
B. Geological Dating
C. Historical Dating
D. Relative DatingWhich of the following is NOT true about Relative Dating?
A. quantitative method of dating
B. principles to recognize the relative ages of rocks
C. used stratigraphy method (oldest found at the bottom and youngest a the top)
D. used to arrange geological events and the rocks they leave behind in sequenceWhich of the following is a principle of Relative Dating?
A. Principle of Half-life
B. Principle of Layering
C. Principle of Superposition
D. Principal of Floral SuccessionWhich of the following is NOT true about Absolute Dating?
A. quantitative method of dating
B. principles to recognize the relative ages of rocks
C. used to give rocks an actual date or date range, in number of years
D. use radiometric method by radioactive decay: concept of isotopes and concepts of half- lifeWhat method of Rock Dating is using stratigraphy method?
A. Absolute Dating
B. Geological Dating
C. Historical Dating
D. Relative Dating
Lesson 1 Relative and Absolute Dating
How old is it? This might be the first question that will enter your mind when you see an old rock or artifact. Certainly, that is one of the first thing that a geologist wants to know.
Geologists find ways on how to determine the age and traces of history from the large number of artifacts and monuments bestowed upon us by older civilization.
There are methods and techniques used by geologists to help them determine the age of the materials that evolved in the past. In this lesson, the relative and absolute dating processes will be discussed.
Figure 1. Rock Layers
[illustration: layered rock cross-section with brick-pattern layer at top, dashed layers, dotted sandstone-like layer, and dashed granite-like layer at bottom]
What’s In
Activity 1: Solving the Earth’s Puzzle!
Directions. Find and encircle relevant words from the puzzle. Then, do the given tasks.
List of Words:
- Rock
- Relative
- Absolute
- Earth
- Age
| A | F | F | E | N | D | F | I | N | D | C |
|---|---|---|---|---|---|---|---|---|---|---|
| D | R | O | C | K | S | A | J | H | T | O |
| M | F | S | R | E | L | A | T | I | V | E |
| A | H | S | A | R | A | G | L | S | U | A |
| B | H | I | O | T | I | E | A | T | S | R |
| C | G | L | R | Z | Y | S | Y | O | A | T |
| A | B | S | O | L | U | T | E | R | N | H |
| D | A | B | S | P | I | O | R | Y | O | R |
| E | F | S | U | L | I | T | S | O | C | O |
Tasks:
- Using a dictionary or any reference, find the meaning of identified words.
- Write sentences out of the identified words from the puzzle.
- Differentiate absolute age from relative age.
Notes to the Teacher This module will help you understand the concepts about how to determine age of rocks. All parts are comprised of activities. Be guided with the instructions on how you will answer. Discuss through any mode the simple principles so the students can proceed to the next activity.
What’s New
We have learned that geologic time is measured in two ways: relative and absolute age. Relative date or age measurement refers only to the order in which events occurred. On the other hand, absolute age is age in years. It tells the order in which events occurred and the exact amount of time that has passed since they occurred.
Activity 2: What’s in the Stack of Rock?
Directions. Look at the diagram of a rock layer. Focus on the sediment layer.
[illustration: two side-by-side rock layer diagrams labeled Limestone, Shale, Sandstone, and Granite]
Figure 2. Sedimentation
Guide Questions:
How will you describe the rocks in the illustrations?
What is/are the use/s of this layering to the geologists?
At which pile of rock can you find the oldest? youngest? Justify your answer.
Can you determine the relative age of the rock based on the layering? How about absolute age?
What does the thickness of each layer indicate?
What is It
Relative Age
Prior to absolute age measurements, geologists used field observations to determine the relative ages. They used simple principle in order to get the relative ages. The following are the principles used by the geologists:
The principle of original horizontality is based on the observation that sediment usually accumulates in horizontal layers. Tectonic forces tilted or folded rocks into an angle after it was formed.
The principle of superposition states that sedimentary rocks become younger from bottom to top. This is because younger layers of the sedimentary always accumulates at the top of the layers. In figure 4, rocks number 5 are oldest and rocks in 1 are the youngest.
The principle of crosscutting relationships is based on the fact that rocks must exist before anything else happened like intrusions or dikecutting across rocks. In figure 5, the cut rock layers are older than the rock that cuts across them.
The principle of faunal succession states that species succeeded one another through time in a definite and recognizable order and that the relative ages of sedimentary rocks can be therefore recognized from their fossils. The absence or the presence may be used to give a relative age of the sedimentary where they are found.
The principle of lateral continuity explained that layers of sediment are continuous. Layers with same rocks but separated by a valley or erosion are initially continuous.
[illustration: horizontal rock layers] Figure 3. Horizontal layers
[illustration: rock layers tilted after deposition, with a diagonal fault line] Figure 4. Tiltation after deposition into horizontal layers
[illustration: rock layers numbered 1 to 5 from top to bottom] Figure 5. The principle of superposition
[illustration: horizontal layers with a dark dike cutting across them] Figure 6. Horizontal layers with dikes
Activity 3: A. Who’s the Oldest?
Directions. Use the letters in the diagram below to determine the age of rocks applying the method of relative dating. List the rock layers from youngest to the oldest relative to age.
[illustration: block diagram of rock layers labeled R, M, H, F, B, and I, with a dike labeled H cutting through]
Figure 7. Rocks layers and dikes
Guide Questions:
In the law of superposition, which layer is the oldest?
What is the relative age of igneous rock in layer H? (younger or older)
What is the youngest rock layer?
What law/principle is represented by layer H as it passes through layer M, F, B, and I?
Which rock layer is older, layer B or layer F?
B. How many years?
Directions. Refer and analyze the diagram below to answer the provided questions.
[chart: diagram of rock layers with fossils and labeled age brackets; Figure 8. Rock Layers and Fossils] Labels:
- 495 mya
- 510 mya
- dating of volcanic ash
- 520 mya
- 545 mya
Figure 8. Rock Layers and Fossils
How old was the youngest rock layer?
How about the oldest rock layer?
What method is used in determining the age of rocks and fossils based on the diagram?
Absolute Age
Since change is the only thing that is permanent, the measurement of absolute age or exact date became a challenging task to the scientists. But they found a natural process that occurs at constant rate and accumulates its record of the radioactive decay of elements in rocks.
Radioactive elements decay because they are composed of unstable isotopes that decompose spontaneously. Each atom has a certain probability of decaying at any time. It has half-life or time for it to decompose into half.
Radioactivity is not affected by geologic process and easily measured in the laboratory. Aside from those, daughter isotopes accumulate in rocks. The longer the rock exists, the more daughter isotopes accumulate. The process of determining the absolute ages of rocks and minerals by measuring the relative amounts of parent and daughter isotopes is called radioactive dating.
e.g. a form of uranium changes (decays) to lead
In the above example, the parent element is uranium (U) and the daughter element is lead (Pb).
Again, the process of radioactive decay can be used for dating rocks because: Radioactive decay proceeds at a constant, regardless of changes in conditions such as temperature, pressure, or the chemical environment.
Here are the commonly used radioactive isotopes in radioactive dating.
Table 1.1 Some Used Isotopes for Radiometric Dating
| Parent Isotope | Daughter Isotope | Half-life (Years) | Effective Dating Range (Years) | Materials that Can be Dated Using this Isotope |
|---|---|---|---|---|
| Carbon-14 | Nitrogen-14 | 5730 | 100-50000 | Wood, shells, or anything that was once alive, Trapped Carbon dioxide |
| Potassium-40 | Argon-40 Calcium-40 | 1.3 billion | 40,000-4.6 billion | Muscovite Biotite Volcanic rock |
| Uranium 238 | Lead 206 | 4.5 billion | 10 million-4.6 billion | Zircon |
| Uranium 235 | Lead 207 | 710 million | 10 million-4.6 billion | Uranite |
Half-Life
It is almost impossible to say when the last of the parent atoms will decay, but the time taken for half the atoms to decay is comparatively easy to predict. The half-life of a radioactive decay process is the time taken for half the original parent atoms to decay.
The length of half-life is a unique feature of each decay process. The half-life of the uranium is 713 million years. This means that if an igneous rock contained 1000 atoms of U-235 when it solidified:
After 713 million years, it would contain 500 atoms of U-235 and 500 atoms of the daughter element for the decay process, Pb-207.
The proportion of parent atoms/daughter atoms present in an igneous rock gives the age of the rock — or the number of million years since the rock solidified
What’s More
Activity 4: Relative vs. Absolute
Age of rocks can be determined through using two methods. These methods are absolute and relative dating.
Directions. Complete the concept map to show the differences between the two methods of dating.
[chart: concept map comparing relative and absolute dating; Activity 4: Relative vs. Absolute] Left column:
- Relative Dating
- Used to arrange geological events, and the rocks they leave behind in sequence
- _____ method of dating
- Used _____ method (oldest found at the bottom and youngest at the top)
Right column:
- Absolute Dating
- Used absolute dating methods, sometimes called numerical dating,to give rocks an actual date,or date range, in number of years.
- _____ method of dating
- Use _____ method by radioactive decay: concept of isotopes and concepts of half- life
Activity 5: Read and Fill!
Directions. Place the missing letters that best complete the term being described by each statement.
| __b__ __l u__ e D __ __i__g | 1. It is used to determine the age of a material by using numeric values. |
| C__o__s C__t_i __g | 2. It states that the geologic feature which cuts another is younger of the two features. |
| R__la__ i __ e __a_i__g | 3. It is used to determine the relative age of rock layers. |
| __up__r__o__i__i__n | 4. This law states that the younger layer is at the top and older layer of rocks are at the bottom. |
| Se__im__nt__ry __ o__ks | 5. These are rocks that usually form deposits that files up and hardened. |
What I Have Learned
- In determining the age of rocks in relative dating, it follows the different principles such as: _____, _____, _____, _____ and _____.
- _____ dating is used to arrange geological events, and the rocks they leave behind in sequence.
- _____ dating is used to give rocks an actual date, or date range, in number of years.
- Relative dating uses stratigraphy method while absolute dating uses _____ method by radioactive decay.
- The _____ of a radioactive decay process is the time taken for half the original parent atoms to decay.
WORD POOL
Relative, Absolute, Superposition, Original Horizontality, Radiometric, Crosscutting, Stratigraphy, Lateral Continuity, Doubling, Half-life, Isotopes, Faunal Succession
What I Can Do
Activity 4: Venn Diagram
Directions. Fill in the Venn diagram to show the similarities and differences between absolute dating and relative dating. Use the words inside the word pool to complete the diagram.
[illustration: blank two-circle Venn diagram with no labels, for completion]
Word Pool
use of numeric value, qualitative method, quantitative method, use the position of rocks, radiometric method, stratigraphic method, used to tell the age of rocks, use sedimentary rocks, give an idea of the order of geologic events, does not give the true age of rocks
Assessment
Directions. Read the following questions and choose the letter of the correct answer. Write the chosen letter on a separate sheet of paper.
Which type of dating method can be used on rock layers by applying the Law of Superposition?
A. Absolute Dating
B. Relative Dating
C. Radioactive Dating
D. Radiometric DatingWhich was the first method used to determine ages of rock and fossils?
A. Absolute Dating
B. Relative Dating
C. Radioactive Dating
D. Radiometric DatingWhat is the difference between an absolute date and a relative date?
A. An absolute date refers to a year or a range of years while a relative date indicates a chronological order.
B. A relative date is derived from radiometric dating techniques while an absolute date comes from guesswork.
C. A relative date refers to a year or a range of years while an absolute date indicates a chronological order.
D. An absolute date involves testing of sedimentary rocks while relative date involves testing of igneous rocks.What method of rock dating is used in giving rocks an actual date?
A. Absolute Dating
B. Geological Dating
C. Historical Dating
D. Relative DatingWhich of the following is NOT true about Relative Dating?
A. quantitative method of dating
B. principles to recognize the relative ages of rocks
C. used to arrange geological events and the rocks they leave behind in sequence
D. used stratigraphy method (oldest found at the bottom and youngest at the top)
Refer to the diagram below and answer the questions that follow.
[illustration: geologic cross-section of layered rock with a V-shaped valley, igneous intrusions, and fault lines; numbered layers and labels printed on it: 1, 3, 6, 4, 5, 6, A, B]
Which layer of the rocks follows the principle of superposition?
A. Layer 1
B. Layer 3
C. Layer 4
D. Layer 6Which layer of the rocks shows the cross-cutting relationship?
A. Layer 1
B. Layer 3
C. Layer 4
D. Layer 6Which of the following is NOT principle of Relative Dating?
A. Superposition
B. Floral Succession
C. Original Horizontality
D. Cross-cutting RelationshipWhich of the following is NOT true about Absolute Dating?
A. It is a quantitative method of dating.
B. It uses simple principles to recognize the relative ages of rocks.
C. It is used to give rocks an actual date, or date range, in number of years.
D. It uses radiometric method by radioactive decay: concept of Isotopes and concepts of half- life.What method of rock dating is using stratigraphy method?
A. Absolute Dating
B. Geological Dating
C. Historical Dating
D. Relative DatingWhich of these is the best indication of the relative age of a rock layer?
A. the thickness of the layer
B. the chemical make-up of the layer
C. the distance of the layer on the surface
D. the position of the layer compared to other layersWhich of the following processes will give an absolute age of a rock?
A. examining the rock’s relative position in a rock outcrop
B. examining the environment in which the rock is found.
C. comparing the size of crystals in the upper and lower parts of the rock
D. comparing the amount of decayed and undecayed radioactive isotopesWhere can you find the youngest fossil in an undisturbed file?
A. on the topmost
B. at the bottom
C. upper part
D. lower partWhich of the following statements best describe principle of horizontality?
A. sediment usually accumulates in horizontal layers.
B. sediment usually accumulates in tilted layers.
C. sediment usually accumulates in alternating rocks.
D. sediment usually accumulates in rounded pile.Which of the following makes use of the position of rocks to determine its age?
A. Relative Dating
B. Absolute Dating
C. Historical Dating
D. Geological Dating
Additional Activities
If you will be asked to determine the age of a rock, which method will you use? Justify you answer.
Answer Key
[transcriber’s note: this page is printed rotated; the boxes below are transcribed in their upright reading order]
What’s More
Activity 4
- Qualitative / Quantitative
- Stratigraphy / Radiometric dating
Activity 5
- Absolute dating
- Cross-cutting
- Relative dating
- Superposition
- Sedimentary rocks
What is It
Activity 3.a
- Layer I
- Younger
- Layer R
- Cross cutting relationship
- Layer B
Activity 3.b A. 495 mya B. 545mya C. Absolute dating
What’s New
Activity 2
- Horizontal layers
- Give relative age of rock/fossils
- Bottom/Topmost
Reason: Original Horizontality - Yes, No
- Thick, large deposition happened
Thin, erosional activity worn the sediments
What I Know
- D
- B
- B
- A
- D
- D
- D
- A
- D
- B
- B
- A
- C
- B
- D
What’s In
Activity 1 Rocks, Relative, Absolute Fossils, History, Earth, Ages Sentences may vary.
Assessment
- B
- B
- A
- A
- A
- D
- B
- B
- B
- D
- D
- D
- B
- A
- D
References
Centricity, accessed February 24, 2019, https://www.lcps.org/cms/lib4/VA01000195/centricity
Companion Websites, accessed February 25, 2019, http://global.oup.com/us/companion.websites/9780195391350/student/c hapt2/Quiz/
Geological Dating, Propofs, accessed February 25,2019, http://www.proprofs.com/quiz-school/story.php?title=geological-dating
Kean, accessed February 25, 2019, http://www.kean.edu/~csmart/Observing/Lectures/Homework08s.doc
Layers of Rock, accessed February 24,2019, https://halletcove.weebly.com/layers-of-rock.html
Quizziz, accessed February 25,2019, https://quizizz.com/admin/quiz/570bb06788512b8d10163a2e
Relative Dating, All About Creation, accessed February 24,2019, https://www.allaboutcreation.org/relative-dating-faq.html
Relative vs. Absolute Dating, accessed February 24,2019, https://science.truck.com/relative-vs-absolute-dating
Thompson, G.R. and Turk, J. 2012. Introduction to Earth Science. Cengage Learning Asia PTE Ltd. (Philippine Branch)
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