Podcast
Questions and Answers
Which earthquake scale is most appropriate for comparing the energy released by a large earthquake in Chile to a smaller earthquake in California?
Which earthquake scale is most appropriate for comparing the energy released by a large earthquake in Chile to a smaller earthquake in California?
- Modified Mercalli scale, because it directly assesses the localized damage caused.
- Volcanic Explosivity Index (VEI), because it integrates multiple data sources for comprehensive assessment.
- Richter scale, because it provides a quick estimate of magnitude from seismograph readings.
- Moment magnitude scale, because it accurately measures total energy released. (correct)
A seismologist is assessing the earthquake risk for a coastal city. Which combination of factors would suggest the highest risk?
A seismologist is assessing the earthquake risk for a coastal city. Which combination of factors would suggest the highest risk?
- High population density, frequent past earthquakes, location near a fault line, and buildings not designed to withstand seismic activity. (correct)
- Low population density, infrequent past earthquakes, and location on a stable, old rock formation.
- Moderate population density, infrequent past earthquakes, geology around a fault line with soft soil, and modern building designs.
- Low population density, proximity to a transform fault, construction adhering to strict seismic codes, and infrequent historical seismic events.
At which type of plate boundary are you most likely to find composite volcanoes?
At which type of plate boundary are you most likely to find composite volcanoes?
- Divergent boundaries, where seafloor spreading allows for decompression melting and basaltic volcanism.
- Hot spots, as mantle plumes rise through the crust and create isolated volcanic activity.
- Transform boundaries, due to the lateral sliding motion of the plates creating pathways for magma.
- Convergent boundaries, where subduction leads to magma generation from the mantle wedge. (correct)
Which of the following characteristics is most indicative of a shield volcano?
Which of the following characteristics is most indicative of a shield volcano?
Why do cinder cone volcanoes typically have moderately explosive eruptions?
Why do cinder cone volcanoes typically have moderately explosive eruptions?
Which type of fault is most commonly found at transform plate boundaries?
Which type of fault is most commonly found at transform plate boundaries?
Which statement accurately describes the relationship between the focus and epicenter of an earthquake?
Which statement accurately describes the relationship between the focus and epicenter of an earthquake?
Why are S-waves crucial in determining that Earth's outer core is liquid?
Why are S-waves crucial in determining that Earth's outer core is liquid?
What is the primary purpose of using the triangulation method with seismic data from multiple stations?
What is the primary purpose of using the triangulation method with seismic data from multiple stations?
Which of the following best describes the motion of particles as a Surface wave passes through the Earth?
Which of the following best describes the motion of particles as a Surface wave passes through the Earth?
If a seismograph station records a significant time lag between the arrival of P-waves and S-waves from an earthquake, what can be inferred about the earthquake's epicenter?
If a seismograph station records a significant time lag between the arrival of P-waves and S-waves from an earthquake, what can be inferred about the earthquake's epicenter?
Consider two seismograph stations, A and B, which are situated at different distances from an earthquake epicenter. Station A is closer to the epicenter than Station B. Which of the following statements accurately compares the arrival times of P-waves and S-waves at the two stations?
Consider two seismograph stations, A and B, which are situated at different distances from an earthquake epicenter. Station A is closer to the epicenter than Station B. Which of the following statements accurately compares the arrival times of P-waves and S-waves at the two stations?
Which seismic wave causes the most significant damage to the Earth's surface during an earthquake?
Which seismic wave causes the most significant damage to the Earth's surface during an earthquake?
Flashcards
Earthquake
Earthquake
Vibrations in the Earth's ground caused by movement of plates along fault lines.
Fault
Fault
A break in Earth's lithosphere where rock masses move relative to each other.
Strike-Slip Fault
Strike-Slip Fault
A fault where rocks slide past each other horizontally.
Normal Fault
Normal Fault
Signup and view all the flashcards
Reverse Fault
Reverse Fault
Signup and view all the flashcards
Seismic Waves
Seismic Waves
Signup and view all the flashcards
Focus
Focus
Signup and view all the flashcards
Epicenter
Epicenter
Signup and view all the flashcards
Richter Scale
Richter Scale
Signup and view all the flashcards
Moment Magnitude Scale
Moment Magnitude Scale
Signup and view all the flashcards
Modified Mercalli Scale
Modified Mercalli Scale
Signup and view all the flashcards
Volcano
Volcano
Signup and view all the flashcards
Shield Volcano
Shield Volcano
Signup and view all the flashcards
Study Notes
- Earthquakes and volcanoes are caused by geological activity
Earthquakes
- Earthquakes are vibrations in the Earth's ground due to the movement of plates at fault lines
- Most occur along plate boundaries
- A fault is a break in Earth's lithosphere where a block of rock moves toward, away from, or past another
Types of Faults
- Strike-slip faults occur at transform plate boundaries
- Normal faults occur at divergent plate boundaries
- Reverse faults occur at convergent plate boundaries
Seismic Waves
- Seismic waves transfer energy through vibration in the earth
- The focus is the point inside the Earth where an earthquake begins
- The epicenter is the location on Earth's surface directly above the focus
Types of Seismic Waves
- Primary waves(P-waves) are the fastest-moving seismic waves and can travel through solids and liquids
- Secondary waves(S-waves) are slower than P-waves and can only travel through solids
- Surface waves move in a rolling motion and cause the most damage to Earth's surface
Earth's Interior
- Scientists discovered that Earth's outer core is liquid because S-waves cannot travel through liquids, while P-waves can travel through both solids and liquids
Finding an Epicenter (Triangulation)
- Determine the difference between the arrival times of P-waves and S-waves (lag time)
- Use an earthquake distance graph to determine the distance from the epicenter
- Draw a circle with the correct distance around the monitoring station and repeat for two more stations
- The intersection of the circles indicates the epicenter
Measuring Earthquakes
- Richter scale measures the amount of ground motion at a given distance
- Moment magnitude scale measures the amount of energy released by an earthquake
- Modified Mercalli scale measures the intensity of an earthquake based on the amount of damage
Earthquake Risks
- Seismologists use five indicators to assess earthquake risk: past earthquakes, probability, population density, geology around a fault, and building designs
Volcanoes
- A volcano is a vent in Earth's crust through which molten rock forms
Where Volcanoes Form
- At convergent boundaries, where one plate subducts under another
- At divergent boundaries, where plates separate and magma rises
- At hot spots, often forming chains of islands
Types of Volcanoes
- Shield volcanoes: large, shield-shaped volcanoes with gentle slopes and gentle eruptions
- Composite volcanoes: large, steep-sided volcanoes resulting from explosive eruptions
- Cinder cone volcanoes: small, steep-sided volcanoes that erupt gas-rich, basaltic lavas with moderately explosive eruptions
- Caldera: large volcanic depression created when the summit collapses during a violent eruption
Types of Eruptions
- Violent eruptions occur when lava has a high viscosity (thick lava) and high gas content
- Quiet eruptions occur when lava has a low viscosity (thin lava) and low gas content
Effects of Volcanic Eruptions
- Lava flows can slowly destroy towns
- Ash fall can cause breathing problems and disrupt air traffic, and cool the climate
- Mudflows can be caused by snow and ice melt mixed with mud and ash
- Pyroclastic flows can be deadly, produced from violent eruptions that eject gas and rock into the air
Predicting Volcanoes
- Prediction methods include observing ground deformation, increases in earthquakes and volcanic gas, and changes in the acidity of nearby water
Climate's Affect
- Volcanic eruptions affect climate through the ash blocking the sun and causing a decrease in global temperatures, and also volcanic rain
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge of earthquakes, seismic waves, volcanoes, and plate tectonics. Explore different earthquake scales, volcanic formations, and fault types. Understand the science behind geological phenomena.
