Earthquakes and Seismotectonics Chapter 5

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Earthquakes and Seismotectonics Chapter 5"

Transcription

1 Earthquakes and Seismotectonics Chapter 5

2 What Creates Earthquakes? The term Earthquake is ambiguous: Applies to general shaking of the ground and to the source of the shaking We will talk about both, but are mainly concerned with the latter Earthquakes occur due to Sudden motion on a fault Formation of a new fault Slip on an existing fault Movement of magma / explosion of a volcano Landslides Meteorite impacts Underground nuclear bomb tests / mine collapses Offset

3 Earthquake Terminology Hypocenter (Focus): actual location of the earthquake at depth Epicenter: location on the surface of the Earth above the hypocenter Hanging Wall: top block of a fault (where a light would hang from) Footwall: bottom block of a fault (where you would stand)

4 Types of Faults In general, faults come in three different types: Normal, Reverse, and Strike-Slip Shallow angle (< 30 ) reverse faults are called thrust faults Faults that have a mix of slip styles are called oblique slip faults See: Fault animations online

5 Why are there different types of faults? Normal Faults: from stretching of or extending rock; points on opposite sides of a fault are father apart after an earthquake Reverse Faults: from contracting or squishing rock; points on opposite sides of the fault are closer together after an earthquake Strike-Slip: can form in either areas of stretching or squishing, material slides laterally past each side of the fault. Described by sense of motion: Right-lateral (Dextral) Left-lateral (Sinistral)

6 Formation of Faults Faults and thus earthquakes form because of stress & strain Plate motion causes rocks to deform or bend Stress and strain become localized Eventually the strength of the rock is overcome BAM!! The rock ruptures and snaps forward releasing the accumulated stress/strain. The process is known as elastic rebound theory Elastic strain: strain that is recoverable New cracks form and link together A through-going fault forms and sliding occurs causing a stress drop

7 Faults & Friction Like a brick sliding across a table, faults, too, are subject to friction Friction, on the micro-scale, is caused by asperities, bumps and irregularities along a surface that resist sliding All other factors equal, faults with more cumulative slip may be smoother and therefore have lower friction (e.g. the San Andreas Fault has very low friction) Once a fault is formed it is a permanent scar that is weaker than the surrounding rock

8 Stick Slip Behavior - Without stick slip behavior, large earthquakes would not happen! - Faults would constantly move (i.e. creep) and not build up significant stress

9 The Earthquake Cycle: A Simple View [ Step 1 ] - Plate motion continues [ Initial Conditions ] - Stress/strain is localized on fault - Plate motion begins - Fence is strained/deformed - Fence is straight - Deformation is recoverable (elastic) [ Step 2 ] - Plate motion continues - Stress/strain exceeds rock strength - The fault slips (ruptures) - Fence is broken into two undeformed pieces

10 Measuring Motion Across a Fault M Great San Francisco Earthquake

11 Locating Earthquakes Often we don t see surface rupture after an EQ Earthquakes occur deep in the Earth. To locate EQ s we can t just look at first arrivals of P-waves Time = 0 is unknown Seismic velocity is non-uniform Can only get a potential epicentral area Instead we rely on the difference in arrival times v s 0.55 v p

12 Locating Earthquakes Because P-waves travel fastest, they will always be recorded first The farther from the source, the more S-wave lag. If we calculate the difference in arrival times of S- and P-waves, we can then calculate the distance to epicenter Called the S-P interval

13 The S-P time only tells distance, not direction A minimum of three stations are needed to calculate epicenter location Called triangulation S-P Intervals

14 One station gives infinite possible epicentral locations Two stations give two possible locations Three stations give one location In practice there is some error The epicenter is located where these circles from multiple stations all intersect Triangulation Station #2 Station #3 Station #1

15 One station gives infinite possible epicentral locations Two stations give two possible locations Three stations give one location In practice there is some error The epicenter is located where these circles from multiple stations all intersect Triangulation

16 How is Earthquake Depth Determined? Seismologists determine hypocenter depth by: Determining the arrival of the pp ray Calculating the p-pp lag time and plugging it into an equation Hypocenter depth also effects S-P intervals, but this is usually accounted for Most regions have earthquakes at a limited range of depth

17 Fault Plane Solutions Along with hypocenter location, seismograms can be used to determine the type of fault that caused the EQ But first we need to review how to quantify the orientation of a plane!

18 Measuring Orientation: Strike and Dip In order to characterize geologic structures, one must be able to quantify the orientation of structures. For Planar features we use: Strike: The orientation of the intersection line between a horizontal surface and the feature of interest. Measured with a compass. E.g. north, N45W, 285, etc Dip: The acute angle between the feature of interest and a horizontal plane. E.g. 0 = horizontal 90 = vertical For linear features we use: Trend: the trend of the line if you were looking down on the feature from above E.g. north, NW, 320, 090, etc Plunge: Acute angle between the line and a horizontal E.g. 46, 75, etc

19 Fault Plane Solutions Consider a peg struck by a hammer Only P-waves to the N-S Greatest amplitude directly ahead and behind i.e. N-S Amplitude decreases away from N-S direction Dilatational first arrival to the S Contractional first arrival to the N Only S-waves to E-W same is true for S-waves almost all first arrivals have the same sense of motion S-waves are of little to no help in determining the fault orientation How do we know if the first arrival is dilatational or contractional?

20 Faults Generate Contraction and Extension The hammer and peg example is too simple Both sides of a fault move Contraction and extension are both generated during slip Geologists call this σ 1 maximum compressive stress direction Seismologists call this P-axis (sometimes C-axis) Pressure axis (compression axis) Extension Contraction Geologists call this σ 3 minimum compressive stress direction Seismologists call this T-axis Tension axis Contraction Extension Fault in a Box

21 Focal Mechanisms Both sides of a fault move, so the radiation pattern is more complex. Seismologists use the pattern of first arrivals to determine several properties of the causative fault strike, dip, and slip vector rake. we call these focal mechanisms, moment tensors, or beach balls Contraction Extension Extension Contraction

22 The Double Couple Mechanism Before an earthquake, rock is sheared The rock cannot rotate, so there must be other stresses involved.

23 The Double Couple Mechanism If two shear stresses are involved the rock can undergo shear strain without rotating called the double couple but this causes ambiguity in the focal mechanism solution

24 The Auxiliary Plane Because of the double couple no rotation is allowed Focal mechanisms predict two potential fault planes collectively called: nodal planes the fault plane the auxillary plane

25 What are the two potential fault orientations? How do we know which is the real fault? Sometimes logic combined with a little Occam s Razor Aftershocks & Historical seismicity How else could we determine the fault plane? Which Plane is the Fault?

26 Geology!!!

27 The Focal Sphere The process just outlined is fine for strike-slip events, but we need a general method for any type of fault. To do this we use the focal sphere just like your favorite part of structural geology Stereonets!!!

28 Strike & Dip: The Stereonet Way Strike = 090 Dip = 90 ⁰ Dip Direction = N/A

29 Strike & Dip: The Stereonet Way Strike = 000 Dip = 90 ⁰ Dip Direction = N/A

30 Strike & Dip: The Stereonet Way Strike = 000 Dip = 80 ⁰ Dip Direction = East +

31 Strike & Dip: The Stereonet Way Strike = 000 Dip = 60 ⁰ Dip Direction = East +

32 Strike & Dip: The Stereonet Way Strike = 000 Dip = 45 ⁰ Dip Direction = East +

33 Strike & Dip: The Stereonet Way Strike = 000 Dip = 30 ⁰ Dip Direction = East +

34 Strike & Dip: The Stereonet Way Strike = 000 Dip = 10 ⁰ Dip Direction = East +

35 Strike & Dip: The Stereonet Way Strike = 045 Dip = 45 ⁰ Dip Direction = SE +

36 Strike & Dip: The Stereonet Way Strike = 135 Dip = 80 ⁰ Dip Direction = SW +

37 Strike & Dip: The Stereonet Way Strike = 280 Dip = 60 ⁰ Dip Direction = NE +

38 Beach Balls For Standard Fault Types For faults with pure dip-slip or pure strike-slip motion the focal mechanisms are relatively straightforward

39 Focal Mechanisms For Oblique Slip Focal mechanisms can also determine the direction of slip Called the slip vector rake, or just rake 180 rake = left-lateral, 180/-180 right-lateral 90 = reverse slip -90 = normal slip 45 =? 120 =?

40 Calculating Focal Mechanisms Although it is impractical to put seismometers deep in the ground, we can still detect waves that are radiated in all directions from a hypocenter We can trace P-waves back to their source using: inverse methods the ray parameter, p We can then calculate the take-off angle relative to vertical this tells seismologists where to plot each station on the focal sphere (stereonet) can get azimuth to source from triangulation

41 Calculating Focal Mechanisms

42 Odd Focal Mechanism? Really think about what the focal sphere represents Why are certain parts are black and others white? This is all black? What could cause this?

Elastic rebound theory

Elastic rebound theory Elastic rebound theory Focus epicenter - wave propagation Dip-Slip Fault - Normal Normal Fault vertical motion due to tensional stress Hanging wall moves down, relative to the footwall Opal Mountain, Mojave

More information

Section 19.1: Forces Within Earth Section 19.2: Seismic Waves and Earth s Interior Section 19.3: Measuring and Locating.

Section 19.1: Forces Within Earth Section 19.2: Seismic Waves and Earth s Interior Section 19.3: Measuring and Locating. CH Earthquakes Section 19.1: Forces Within Earth Section 19.2: Seismic Waves and Earth s Interior Section 19.3: Measuring and Locating Earthquakes Section 19.4: Earthquakes and Society Section 19.1 Forces

More information

San Andreas Movie Can It Happen?

San Andreas Movie Can It Happen? San Andreas Movie Can It Happen? Learning Objectives (LO) Lecture 14: Faults and Quakes Read: Chapter 10 and 11 Homework #12 due Thursday 12pm What we ll learn today:! 1. Compare strike-slip to dip-slip

More information

Learning goals - January 16, Describe the geometry of a fault (1) orientation of the plane (strike and dip) (2) slip vector

Learning goals - January 16, Describe the geometry of a fault (1) orientation of the plane (strike and dip) (2) slip vector Learning goals - January 16, 2012 You will understand how to: Describe the geometry of a fault (1) orientation of the plane (strike and dip) (2) slip vector Understand concept of slip rate and how it is

More information

Apparent and True Dip

Apparent and True Dip Apparent and True Dip Cross-bedded building stone. The contact immediately below A appears to dip gently to the right, but at B, the contact appears to dip to the left. But it's not a syncline! Both of

More information

Read & Learn Earthquakes & Faults

Read & Learn Earthquakes & Faults Read Earthquakes & Faults Read the provided article. Use the information in the reading to answer the questions on the task cards on your answer sheet. Make sure your answers are in the correct spot on

More information

Figure Diagram of earth movements produced by (a) P-waves and (b) S-waves.

Figure Diagram of earth movements produced by (a) P-waves and (b) S-waves. Geology 101 Name(s): Lab 10: Earthquakes When the stresses in a rock (which may or may not already be faulted) exceed the tensile strength of the rock, the rock ruptures at a point called the focus or

More information

Forces in Earth s Crust

Forces in Earth s Crust Forces in Earth s Crust This section explains how stresses in Earth s crust cause breaks, or faults, in the crust. The section also explains how faults and folds in Earth s crust form mountains. Use Target

More information

1 How and Where Earthquakes Happen

1 How and Where Earthquakes Happen CHAPTER 12 1 How and Where Earthquakes Happen SECTION Earthquakes KEY IDEAS As you read this section, keep these questions in mind: What is elastic rebound? What are the similarities and differences between

More information

4 Deforming the Earth s Crust

4 Deforming the Earth s Crust CHAPTER 7 4 Deforming the Earth s Crust SECTION Plate Tectonics BEFORE YOU READ After you read this section, you should be able to answer these questions: What happens when rock is placed under stress?

More information

Brittle Deformation. Earth Structure (2 nd Edition), 2004 W.W. Norton & Co, New York Slide show by Ben van der Pluijm

Brittle Deformation. Earth Structure (2 nd Edition), 2004 W.W. Norton & Co, New York Slide show by Ben van der Pluijm Lecture 6 Brittle Deformation Earth Structure (2 nd Edition), 2004 W.W. Norton & Co, New York Slide show by Ben van der Pluijm WW Norton, unless noted otherwise Brittle deformation EarthStructure (2 nd

More information

Sumatra December 26,

Sumatra December 26, Earthquakes Sumatra December 26, 2004 9.1 Before After Haiti January 12, 2010 7.0 230,000 dead 300,000 injured 1,000,000 homeless Chile February 27, 2010 8.8 China April 14, 2010 7.1 Japan March 11,

More information

Dangerous tsunami threat off U.S. West Coast

Dangerous tsunami threat off U.S. West Coast Earthquakes Ch. 12 Dangerous tsunami threat off U.S. West Coast Earthquakes What is an Earthquake? It s the shaking and trembling of the Earth s crust due to plate movement. The plates move, rocks along

More information

Earthquakes Chapter 19

Earthquakes Chapter 19 Earthquakes Chapter 19 Does not contain complete lecture notes. What is an earthquake An earthquake is the vibration of Earth produced by the rapid release of energy Energy released radiates in all directions

More information

11/30/16 EARTHQUAKES ELASTIC LIMIT FAULT FORCE AND PLATES WHAT DO YOU NOTICE?

11/30/16 EARTHQUAKES ELASTIC LIMIT FAULT FORCE AND PLATES WHAT DO YOU NOTICE? ELASTIC LIMIT EARTHQUAKES Bend sitck but do not break it. What do you notice? No bend until it breaks. Describe the energy and forces at work. (Kinetic, potential etc) 8 TH GRADE FAULT FORCE AND PLATES

More information

Determining the Earthquake Epicenter: Japan

Determining the Earthquake Epicenter: Japan Practice Name: Hour: Determining the Earthquake Epicenter: Japan Measuring the S-P interval There are hundreds of seismic data recording stations throughout the United States and the rest of the world.

More information

Forces in Earth s Crust

Forces in Earth s Crust Name Date Class Earthquakes Section Summary Forces in Earth s Crust Guide for Reading How does stress in the crust change Earth s surface? Where are faults usually found, and why do they form? What land

More information

The Earthquake Cycle Chapter :: n/a

The Earthquake Cycle Chapter :: n/a The Earthquake Cycle Chapter :: n/a A German seismogram of the 1906 SF EQ Image courtesy of San Francisco Public Library Stages of the Earthquake Cycle The Earthquake cycle is split into several distinct

More information

LAB 6: Earthquakes & Faults

LAB 6: Earthquakes & Faults Name School LAB 6: Earthquakes & Faults An earthquake is what happens when two blocks of the earth suddenly slip past one another. The surface where they slip is called the fault or fault plane. The location

More information

ESSENTIAL QUESTION. How can I describe earthquakes?

ESSENTIAL QUESTION. How can I describe earthquakes? Standard S6E5: Students will understand how the distribution of land and oceans affects climate and weather. d: describe the processes that change rocks and the surface of Earth e: Recognize that lithospheric

More information

PEAT SEISMOLOGY Lecture 12: Earthquake source mechanisms and radiation patterns II

PEAT SEISMOLOGY Lecture 12: Earthquake source mechanisms and radiation patterns II PEAT8002 - SEISMOLOGY Lecture 12: Earthquake source mechanisms and radiation patterns II Nick Rawlinson Research School of Earth Sciences Australian National University Waveform modelling P-wave first-motions

More information

Earthquakes = shaking of Earth because of a rapid release of energy

Earthquakes = shaking of Earth because of a rapid release of energy There are more than 30,000 earthquakes worldwide each year! Earthquakes = shaking of Earth because of a rapid release of energy usually because of movement of tectonic plates Most earthquakes last for

More information

ES Ch 19 Earthquakes 1

ES Ch 19 Earthquakes 1 Chapter 19 - Earthquakes Objectives 1. Define stress vs. strain as they apply to rocks. 2. Define faults. 3. Contrast types of seismic waves-3 types according to their type of movement, speed, location

More information

Chapter 4 Earthquakes and Tsunamis

Chapter 4 Earthquakes and Tsunamis Geology of the Hawaiian Islands Class 21 30 March 2004 100 100 100 96 A B C D F Exam Scores 95 94 94 90 85 83 83 83 Mean 72 67 61 59 59 55 54 41 Mean = 78.5 Median = 83 Any Questions? Chapter 4 Earthquakes

More information

Magnitude 7.6 & 7.4 SOLOMON ISLANDS

Magnitude 7.6 & 7.4 SOLOMON ISLANDS A magnitude 7.6 earthquake struck near the Solomon Islands on Sunday morning local time; there were no immediate reports of damage. The earthquake was centered 100 km (60 miles) south of Kira Kira, a town

More information

Once you have opened the website with the link provided choose a force: Earthquakes

Once you have opened the website with the link provided choose a force: Earthquakes Name: Once you have opened the website with the link provided choose a force: Earthquakes When do earthquakes happen? On the upper left menu, choose number 1. Read What is an Earthquake? Earthquakes happen

More information

Earthquakes Earth, 9th edition, Chapter 11 Key Concepts What is an earthquake? Earthquake focus and epicenter What is an earthquake?

Earthquakes Earth, 9th edition, Chapter 11 Key Concepts What is an earthquake? Earthquake focus and epicenter What is an earthquake? 1 2 3 4 5 6 7 8 9 10 Earthquakes Earth, 9 th edition, Chapter 11 Key Concepts Earthquake basics. "" and locating earthquakes.. Destruction resulting from earthquakes. Predicting earthquakes. Earthquakes

More information

Plate Tectonics and Earth s Structure

Plate Tectonics and Earth s Structure Plate Tectonics and Earth s Structure Chapter Eight: Plate Tectonics Chapter Nine: Earthquakes Chapter Ten: Volcanoes Chapter Nine: Earthquakes 9.1 What is an Earthquake? 9.2 Seismic Waves 9.3 Measuring

More information

Forces in Earth s Crust

Forces in Earth s Crust Forces in Earth s Crust (pages 180 186) Types of Stress (page 181) Key Concept: Tension, compression, and shearing work over millions of years to change the shape and volume of rock. When Earth s plates

More information

I. What are Earthquakes?

I. What are Earthquakes? I. What are Earthquakes? A. There is more to earthquakes than just the shaking of the ground. An entire branch of Earth science, called seismology, is devoted to the study of earthquakes. B. Earthquakes

More information

A Closer Look At Body Wave Magnitude & Introduction To Moment Magnitude

A Closer Look At Body Wave Magnitude & Introduction To Moment Magnitude A Closer Look At Body Wave Magnitude & Introduction To Moment Magnitude Previously we have learned the mechanics of calculating earthquake magnitudes with several magnitude scales: Duration Magnitude,

More information

Lab 6: Earthquake Focal Mechanisms (35 points)

Lab 6: Earthquake Focal Mechanisms (35 points) Lab 6: Earthquake Focal Mechanisms (35 points) Group Exercise 1. Drawing Nodal Planes (8 pts) The outline map below labeled Figure 4.60a shows the positions of two earthquakes recorded on the Mid-Atlantic

More information

Earthquakes.

Earthquakes. Earthquakes http://thismodernworld.com/comic-archive Elastic rebound http://projects.crustal.ucsb.edu/understanding/elastic/rebound.html Elastic rebound Rocks store energy elastically When stored stress

More information

Figure Diagram of earth movements produced by (a) P-waves and (b) S-waves.

Figure Diagram of earth movements produced by (a) P-waves and (b) S-waves. Geology 101 Name(s): Lab 11: Earthquakes When the stresses in a rock (which may or may not already be faulted) exceed the tensile strength of the rock, the rock ruptures at a point called the focus or

More information

INTRODUCTION TO EARTHQUAKES

INTRODUCTION TO EARTHQUAKES INTRODUCTION TO EARTHQUAKES Seismology = Study of earthquakes Seismologists = Scientists who study earthquakes Earthquake = Trembling or shaking of the earth s surface, usually as a result of the movement

More information

How Do Scientists Find the Epicenter of an Earthquake?

How Do Scientists Find the Epicenter of an Earthquake? 3.4 Explore How Do Scientists Find the Epicenter of an Earthquake? Seismograph data says that the earthquake is 100 km (62 mi) away, but at which point on the circle is the earthquake located? EE 116 3.4

More information

Moho (Mohorovicic discontinuity) - boundary between crust and mantle

Moho (Mohorovicic discontinuity) - boundary between crust and mantle Earth Layers Dynamic Crust Unit Notes Continental crust is thicker than oceanic crust Continental Crust Thicker Less Dense Made of Granite Oceanic Crust Thinner More Dense Made of Basalt Moho (Mohorovicic

More information

Lab 7: Earthquakes. Figure 7-1. Diagram of earth movements produced by (a) P-waves and (b) S-waves.

Lab 7: Earthquakes. Figure 7-1. Diagram of earth movements produced by (a) P-waves and (b) S-waves. Geology 101 Name(s): Lab 7: Earthquakes When the stresses in a rock (which may or may not already be faulted) exceed the tensile strength of the rock, the rock ruptures at a point called the focus or hypocenter.

More information

Magnitude 7.6 & 7.6 PERU

Magnitude 7.6 & 7.6 PERU Two deep 7.6 magnitude earthquakes have shaken a sparsely populated jungle region near the Peru-Brazil border in southeast Peru. There were no immediate reports of injuries or damage. The second M 7.6

More information

Earthquakes. Earthquakes and Plate Tectonics. Earthquakes and Plate Tectonics. Chapter 6 Modern Earth Science. Modern Earth Science. Section 6.

Earthquakes. Earthquakes and Plate Tectonics. Earthquakes and Plate Tectonics. Chapter 6 Modern Earth Science. Modern Earth Science. Section 6. Earthquakes Chapter 6 Modern Earth Science Earthquakes and Plate Tectonics Section 6.1 Modern Earth Science Earthquakes and Plate Tectonics Earthquakes are the result of stresses in Earth s s lithosphere.

More information

Name Class Date. 1. What is the outermost layer of the Earth called?. a. core b. lithosphere c. asthenosphere d. mesosphere

Name Class Date. 1. What is the outermost layer of the Earth called?. a. core b. lithosphere c. asthenosphere d. mesosphere Name Class Date Assessment Geology Plate Tectonics MULTIPLE CHOICE Write the letter of the correct answer in the space provided. 1. What is the outermost layer of the Earth called?. a. core b. lithosphere

More information

Use a highlighter to mark the most important parts, or the parts. you want to remember in the background information.

Use a highlighter to mark the most important parts, or the parts. you want to remember in the background information. P a g e 1 Name A Fault Model Purpose: To explore the types of faults and how they affect the geosphere Background Information: A fault is an area of stress in the earth where broken rocks slide past each

More information

5. What is an earthquake 6. Indicate the approximate radius of the earth, inner core, and outer core.

5. What is an earthquake 6. Indicate the approximate radius of the earth, inner core, and outer core. Tutorial Problems 1. Where Do Earthquakes Happen? 2. Where do over 90% of earthquakes occur? 3. Why Do Earthquakes Happen? 4. What are the formulae for P and S velocity 5. What is an earthquake 6. Indicate

More information

Earthquake Notes. Earthquakes occur all the time all over the world, both along plate edges and along faults.

Earthquake Notes. Earthquakes occur all the time all over the world, both along plate edges and along faults. Earthquake Notes Name: Date: Where Do Earthquakes Happen? Earthquakes occur all the time all over the world, both along plate edges and along faults. Most earthquakes occur along the edge of the oceanic

More information

Learning Objectives (LO) What we ll learn today:!

Learning Objectives (LO) What we ll learn today:! Learning Objectives (LO) Lecture 13: Mountain Building Read: Chapter 10 Homework #11 due Tuesday 12pm What we ll learn today:! 1. Define the types of stress that are present in the crust! 2. Define the

More information

The Frictional Regime

The Frictional Regime The Frictional Regime Processes in Structural Geology & Tectonics Ben van der Pluijm WW Norton+Authors, unless noted otherwise 1/25/2016 10:08 AM We Discuss The Frictional Regime Processes of Brittle Deformation

More information

Internal Layers of the Earth

Internal Layers of the Earth Lecture #4 notes Geology 3950, Spring 2006; CR Stern Seismic waves, earthquake magnitudes and location, and internal earth structure (pages 28-95 in the 4 th edition and 28-32 and 50-106 in the 5 th edition)

More information

Answer sheet for question 1 Answer question 1 as soon as the sample arrives at your desk.

Answer sheet for question 1 Answer question 1 as soon as the sample arrives at your desk. EAS 233 Geologic structures. Final test. April 2012. 3 hours. Answer question 1 and 2 and three other questions. If you start more than the required number of questions, clearly delete the answers you

More information

Section 3 Deforming Earth s Crust

Section 3 Deforming Earth s Crust Section 3 Deforming Earth s Crust Key Concept Tectonic plate motions deform Earth s crust. Deformation causes rock layers to bend and break and causes mountains to form. What You Will Learn Stress is placed

More information

2.3 Notes: Earthquake Damage Can Be Reduced

2.3 Notes: Earthquake Damage Can Be Reduced 2.3 Notes: Earthquake Damage Can Be Reduced Earthquakes can cause severe damage and loss of life Each year, there is about one earthquake with a magnitude of or higher-this is an extremely earthquake.

More information

Magnitude 7.7 QUEEN CHARLOTTE ISLANDS REGION

Magnitude 7.7 QUEEN CHARLOTTE ISLANDS REGION A major 7.7 magnitude earthquake struck at 8:04 PM local time in western British Columbia, Canada. The epicenter is located on Moresby Island, the southern large island in the Queen Charlotte Islands region.

More information

The Earthquake Machine: What 1906 taught us about how earthquakes work

The Earthquake Machine: What 1906 taught us about how earthquakes work A Series of Ten Short Articles for Students, Teachers, and Families 1 Earthquake Science Feature 1 of 10 The Earthquake Machine: What 1906 taught us about how earthquakes work On April 18, 1906, the earth

More information

Earthquakes 11/14/2014. Earthquakes Occur at All Boundaries. Earthquakes. Key Aspects of an Earthquake. Epicenter. Focus

Earthquakes 11/14/2014. Earthquakes Occur at All Boundaries. Earthquakes. Key Aspects of an Earthquake. Epicenter. Focus Earthquakes Earthquakes Caused by friction and movement between Earth s tectonic plates A release of force Often caused by a catch between two plates As plates slide by, they stick to each other When the

More information

Magnitude 7.1 PERU. There are early reports of homes and roads collapsed leaving one dead and several dozen injured.

Magnitude 7.1 PERU. There are early reports of homes and roads collapsed leaving one dead and several dozen injured. A magnitude 7.1 earthquake has occurred offshore Peru. The earthquake struck just after 4 a.m. local time and was centered near the coast of Peru, 40 km (25 miles) south-southwest of Acari, Peru at a depth

More information

Chapter 19 Earthquakes. Shake, Rattle & Roll

Chapter 19 Earthquakes. Shake, Rattle & Roll Chapter 19 Earthquakes Shake, Rattle & Roll 19.1 Forces within OBJECTIVES Define stress and strain as they apply to rocks. Distinguish among the three different fault types. Contrast three types of seismic

More information

RELOCATION OF THE MACHAZE AND LACERDA EARTHQUAKES IN MOZAMBIQUE AND THE RUPTURE PROCESS OF THE 2006 Mw7.0 MACHAZE EARTHQUAKE

RELOCATION OF THE MACHAZE AND LACERDA EARTHQUAKES IN MOZAMBIQUE AND THE RUPTURE PROCESS OF THE 2006 Mw7.0 MACHAZE EARTHQUAKE RELOCATION OF THE MACHAZE AND LACERDA EARTHQUAKES IN MOZAMBIQUE AND THE RUPTURE PROCESS OF THE 2006 Mw7.0 MACHAZE EARTHQUAKE Paulino C. FEITIO* Supervisors: Nobuo HURUKAWA** MEE07165 Toshiaki YOKOI** ABSTRACT

More information

Deformation of the Crust

Deformation of the Crust Deformation of the Crust Review Choose the best response. Write the letter of that choice in the space provided. 1. The state of balance between the thickness of the crust and the depth at which it rides

More information

Topic 5: The Dynamic Crust (workbook p ) Evidence that Earth s crust has shifted and changed in both the past and the present is shown by:

Topic 5: The Dynamic Crust (workbook p ) Evidence that Earth s crust has shifted and changed in both the past and the present is shown by: Topic 5: The Dynamic Crust (workbook p. 65-85) Evidence that Earth s crust has shifted and changed in both the past and the present is shown by: --sedimentary horizontal rock layers (strata) are found

More information

Earthquake Hazards in the San Francisco Bay Region:

Earthquake Hazards in the San Francisco Bay Region: Earthquake Hazards in the San Francisco Bay Region: Kent A Fogleman National Strong-Motion Project Earthquake Science Center U. S. Geological Survey Menlo Park, CA 10.5 THE DAY THE EARTH WOULD NOT STAND

More information

Chapter Review USING KEY TERMS. asthenosphere uplift continental drift. known as. tectonic plates move. object. UNDERSTANDING KEY IDEAS

Chapter Review USING KEY TERMS. asthenosphere uplift continental drift. known as. tectonic plates move. object. UNDERSTANDING KEY IDEAS Skills Worksheet Chapter Review USING KEY TERMS 1. Use the following terms in the same sentence: crust, mantle, and core. Complete each of the following sentences by choosing the correct term from the

More information

Description of faults

Description of faults GLG310 Structural Geology Description of faults Horizontal stretch Crustal thickness Regional elevation Regional character Issues Normal Thrust/reverse Strike-slip >1 1 in one direction and < 1 in

More information

Lecture Outlines PowerPoint. Chapter 7 Earth Science 11e Tarbuck/Lutgens

Lecture Outlines PowerPoint. Chapter 7 Earth Science 11e Tarbuck/Lutgens Lecture Outlines PowerPoint Chapter 7 Earth Science 11e Tarbuck/Lutgens 2006 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the use of instructors

More information

EARTHQUAKES AND EARTH S INTERIOR. Objectives. Megathrust earthquakes

EARTHQUAKES AND EARTH S INTERIOR. Objectives. Megathrust earthquakes EARTHQUAKES AND EARTH S INTERIOR Objectives Explain the connection between earthquakes and plate tectonics. Identify several earthquake-related hazards. Define body waves and surface waves. Explain how

More information

Tectonic Plates Test Study Guide Answers

Tectonic Plates Test Study Guide Answers Tectonic Plates Test Study Guide Answers Weathering and Erosion 1. What is the difference between weathering and erosion? Weathering is the breakdown of earth materials and erosion is the movement of earth

More information

Science of Natural Disasters: Earthquakes! 6 April Rebecca Clotts Department of Geology, University of St Thomas

Science of Natural Disasters: Earthquakes! 6 April Rebecca Clotts Department of Geology, University of St Thomas Science of Natural Disasters: Earthquakes! 6 April 2016 Rebecca Clotts Department of Geology, University of St Thomas 1 What is an earthquake? An episode of ground shaking Any earthquakes today? http://earthquake.usgs.gov/

More information

PART 7: PLATE TECTONICS, EARTHQUAKES & VOLCANOES

PART 7: PLATE TECTONICS, EARTHQUAKES & VOLCANOES PART 7: PLATE TECTONICS, EARTHQUAKES & VOLCANOES 1. Theory of Plate Tectonics: a theory born in 1968 that there are massive rock plates under the surface of the Earth called tectonic plates that are in

More information

Chapter Introduction Lesson 1 Earthquakes Lesson 2 Volcanoes Chapter Wrap-Up

Chapter Introduction Lesson 1 Earthquakes Lesson 2 Volcanoes Chapter Wrap-Up Chapter Introduction Lesson 1 Earthquakes Lesson 2 Volcanoes Chapter Wrap-Up What causes earthquakes and volcanic eruptions? What do you think? Before you begin, decide if you agree or disagree with each

More information

MAR110 Lecture #5 Plate Tectonics-Earthquakes

MAR110 Lecture #5 Plate Tectonics-Earthquakes 1 MAR110 Lecture #5 Plate Tectonics-Earthquakes Figure 5.0 Plate Formation & Subduction Destruction The formation of the ocean crust from magma that is upwelled into a pair of spreading centers. Pairs

More information

Magnitude 7.3 OFFSHORE EL SALVADOR

Magnitude 7.3 OFFSHORE EL SALVADOR A magnitude 7.3 earthquake struck off the Pacific coast of Central America late Monday night, early reports indicate one death. The earthquake occurred at a depth of 40 km (24.9 miles). Its epicenter was

More information

Lab 11: Earthquakes. Figure 7-1. Diagram of earth movements produced by (a) P-waves and (b) S-waves.

Lab 11: Earthquakes. Figure 7-1. Diagram of earth movements produced by (a) P-waves and (b) S-waves. Geology 101 Name(s): Lab 11: Earthquakes When the stresses in a rock (which may or may not already be faulted) exceed the tensile strength of the rock, the rock ruptures at a point called the focus or

More information

Anatomy of an Earthquake Focus (or hypocentre): the center of energy release.

Anatomy of an Earthquake Focus (or hypocentre): the center of energy release. Anatomy of an Earthquake Focus (or hypocentre): the center of energy release. Epicentre: the point on the ground surface immediately above the focus (closest point on the surface to the focus). Types of

More information

Boundaries, Stresses, and Faults OH MY! How do geologic events change and shape Earth s surface?

Boundaries, Stresses, and Faults OH MY! How do geologic events change and shape Earth s surface? Boundaries, Stresses, and Faults OH MY! How do geologic events change and shape Earth s surface? Remember The Lithosphere is made of The CRUST + The Upper Rigid Mantle Plates may be called by different

More information

Multi-station Seismograph Network

Multi-station Seismograph Network Multi-station Seismograph Network Background page to accompany the animations on the website: IRIS Animations Introduction One seismic station can give information about how far away the earthquake occurred,

More information

How Do We Know Where an Earthquake Originated? Teacher's Guide

How Do We Know Where an Earthquake Originated? Teacher's Guide How Do We Know Where an Earthquake Originated? Teacher's Guide Standard Addressed: Grades 6-8: Scientific Inquiry 1 B/1, 2 Mathematical Inquiry 2 C/2 Technology and Science 3 A/2 Processes that shape the

More information

Rock Slope Analysis Small and Large Scale Failures Mode of Failure Marklands Test To establish the possibility of wedge failure. Plane failure is a special case of wedge failure. Sliding along

More information

Slinky Lab- Simulating the Motion of Earthquake Waves.

Slinky Lab- Simulating the Motion of Earthquake Waves. Name Date Period Slinky Lab- Simulating the Motion of Earthquake Waves. Background: You will utilize a slinky to model earthquake waves, learn the speed, direction and behavior of different waves which

More information

Identifying the causes and effects of earthquakes

Identifying the causes and effects of earthquakes Science 3 Physical Earth and Space Life LESSON 57 Identifying the causes and effects of earthquakes Lesson Preparation Program Materials Child s Booklet E Exploring the Earth s Structure (pp. 12 13) Optional:

More information

friction friction a-b slow fast increases during sliding

friction friction a-b slow fast increases during sliding µ increases during sliding faster sliding --> stronger fault --> slows sliding leads to stable slip: no earthquakes can start velocity-strengthening friction slow fast µ velocity-strengthening friction

More information

The Earthquake of Padang, Sumatra of 30 September 2009 scientific information and update

The Earthquake of Padang, Sumatra of 30 September 2009 scientific information and update The Earthquake of Padang, Sumatra of 30 September 2009 scientific information and update 01-October-2009 Christophe Vigny Directeur de recherches at CNRS Laboratoire de Géologie Geoscience Dept. Of ENS,

More information

Earthquake information

Earthquake information Name: Date: Block Earthquake information The graph below shows travel time in minutes and distance traveled for primary and secondary waves. Primary and secondary waves start at the same time but do not

More information

Mountains, like those shown in Figure 1, provide some of the most

Mountains, like those shown in Figure 1, provide some of the most Section 11.1 11.1 Rock Deformation 1 FOCUS Section Objectives 11.1 Identify the factors that determine the strength of a rock and how it will deform. 11.2 Explain how rocks permanently deform. 11.3 Distinguish

More information

ES 104 # 5 EARTHQUAKES:

ES 104 # 5 EARTHQUAKES: ES 104 Laboratory # 5 EARTHQUAKES: Epicenter Determination, Seismic Waves, and Hazards Introduction Earthquakes are vibrations of Earth caused by large releases of energy that accompany volcanic eruptions,

More information

Layers of the Earth Date: SWABT: Identify and describe the layers of the Earth and their characteristics

Layers of the Earth Date: SWABT: Identify and describe the layers of the Earth and their characteristics Layers of the Earth SWABT: Identify and describe the layers of the Earth and their characteristics CRUST Composition: Thickness: State of Matter: : Mostly Basalt : Mostly Granite : Crust and Upper Mantle

More information

The Solid Earth Chapter 4 Answers to selected questions. (1) Love waves involve transverse motion, generally arrive before Rayleigh waves.

The Solid Earth Chapter 4 Answers to selected questions. (1) Love waves involve transverse motion, generally arrive before Rayleigh waves. The Solid Earth Chapter 4 Answers to selected questions (1) Love waves involve transverse motion, generally arrive before Rayleigh waves. () (a) T = 10 s, v ~4 kms -1, so wavelength is ~40 km. (b) T =

More information

In this lab, we will study and analyze geologic maps from a few regions, including the Grand Canyon, western Wyoming, and coastal California.

In this lab, we will study and analyze geologic maps from a few regions, including the Grand Canyon, western Wyoming, and coastal California. Name: Lab Section: work in groups, but each person turns in his/her own GEOSCIENCE 001 LAB UNDERSTANDING GEOLOGIC MAPS Geologic maps are colorful and even beautiful, but they also contain an amazing amount

More information

Earth Science Ch. 5.1 Ch. 5 Vocabulary List Lesson 1: Earth s Moving Plates

Earth Science Ch. 5.1 Ch. 5 Vocabulary List Lesson 1: Earth s Moving Plates Earth Science Ch. 5.1 Ch. 5 Vocabulary List Lesson 1: Earth s Moving Plates Name # Teacher + 22 Use your textbook s glossary & index to help you define the following words. (2 points each) & Sketch (optional)

More information

Magnitude 8.2 NORTHWEST OF IQUIQUE, CHILE

Magnitude 8.2 NORTHWEST OF IQUIQUE, CHILE An 8.2-magnitude earthquake struck off the coast of northern Chile, generating a local tsunami. The USGS reported the earthquake was centered 95 km (59 miles) northwest of Iquique at a depth of 20.1km

More information

Plate Tectonics Unit II: Plate Boundaries (3.5 pts)

Plate Tectonics Unit II: Plate Boundaries (3.5 pts) T. James Noyes, El Camino College Plate Tectonics Unit II: The Plate Boundaries (Topic 11A-2) page 1 Name: Section: Plate Tectonics Unit II: Plate Boundaries (3.5 pts) Plate Boundaries We will now discuss

More information

Magnitude 7.0 NEW CALEDONIA

Magnitude 7.0 NEW CALEDONIA A magnitude 7.0 earthquake has occurred 82km ENE of Maré Island, the secondlargest of the Loyalty Islands in the archipelago of New Caledonia. The initial report of the magnitude and shallow 10km depth

More information

The seismotectonic significance of the seismic swarm in the Brabant Massif (Belgium)

The seismotectonic significance of the seismic swarm in the Brabant Massif (Belgium) The seismotectonic significance of the 2008-2010 seismic swarm in the Brabant Massif (Belgium) Koen VAN NOTEN, Thomas LECOCQ, Thierry CAMELBEECK Seismology-Gravimetry, Royal Observatory of Belgium, Brussels,

More information

Magnitude 7.3 NEPAL. Tuesday, May 12, 2015 at 07:05:19 UTC

Magnitude 7.3 NEPAL. Tuesday, May 12, 2015 at 07:05:19 UTC A magnitude 7.3 earthquake has occurred near Mount Everest. Early reports suggest 32 people have been killed and at least 1,000 were injured in the earthquake. The region is still in recovery from a 7.8

More information

A Model of Three Faults

A Model of Three Faults A Model of Three Faults Grades 7-12 Adapted from the USGS Learning Web Lesson Plans Background One of the most frightening and destructive phenomena of nature is a severe earthquake and its terrible aftereffects.

More information

Crustal deformation in Taiwan: Results from finite source inversions of six M w > 5.8 Chi-Chi aftershocks

Crustal deformation in Taiwan: Results from finite source inversions of six M w > 5.8 Chi-Chi aftershocks JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109,, doi:10.1029/2003jb002606, 2004 Crustal deformation in Taiwan: Results from finite source inversions of six M w > 5.8 Chi-Chi aftershocks Wu-Cheng Chi 1 and Doug

More information

The Theory of Plate Tectonics - Boundaries, Stresses, and Faults

The Theory of Plate Tectonics - Boundaries, Stresses, and Faults The Theory of Plate Tectonics - Boundaries, Stresses, and Faults 1. What is the theory of plate tectonics? 2. What are the three types of plate boundaries? What are Plates? The Earth s crust and upper

More information

ANALYSIS OF A SLOPE FAILURE IN AN OPEN PIT MINE USING TSLOPE

ANALYSIS OF A SLOPE FAILURE IN AN OPEN PIT MINE USING TSLOPE ANALYSIS OF A SLOPE FAILURE IN AN OPEN PIT MINE USING TSLOPE 1. Background In 1996 a slope failure occurred at the Round Hill open pit mine, operated by Macraes Mining Company Ltd. The failure as shown

More information

Faults, Fossils, Rocks and Minerals Review:

Faults, Fossils, Rocks and Minerals Review: Faults, Fossils, Rocks and Minerals Review: 1. The preserved remains or traces of organisms that lived in the past are. - Fossils 2. How do Fossils form? - A dead organism becomes buried in sediment 3.

More information

5. EARTHQUAKES AND EARTH S INTERIOR

5. EARTHQUAKES AND EARTH S INTERIOR LAST NAME (ALL IN CAPS): FIRST NAME: 5. EARTHQUAKES AND EARTH S INTERIOR EARTHQUAKE An earthquake is ground shaking caused by sudden and rapid movement of one block of rock slipping past another along

More information

Geologic Structures and Processes/Orogenesis

Geologic Structures and Processes/Orogenesis Geologic Structures and Processes/Orogenesis Plate Boundaries Parks and Plates 2005 Robert J. Lillie Earthquake Epicenters Volcanic Activity Faults Faults Types of dip-slip faults Normal fault» Hanging

More information

LAB 9: Earthquakes & Seismic Activity

LAB 9: Earthquakes & Seismic Activity LAB 9: Earthquakes & Seismic Activity Objectives Identify P, S, and surface waves on a simple seismogram Locate the epicenter of an earthquake using seismograms and travel times curves Describe how the

More information

Earthquakes in Barcelonnette!

Earthquakes in Barcelonnette! Barcelonnette in the Ubaye valley : the landscape results of large deformations during the alpine orogene (40 5 Myr in this area) and the succession of Quaternary glaciations. The sedimentary rocks are

More information