levo

Hazardous Earth

Earthquake-triggered landslides, avalanches and flooding

  • 2 things to know
  • Component 03

Overview

Recall questions on why shaking triggers landslides and which slopes fail, landslides in the 2008 Sichuan earthquake, landslide dams and how they are made safe, avalanches at Yungay in 1970 and after the 2015 Nepal earthquake, flooding from failed dams, levees and subsidence, and what makes a landslide a disaster.

What you need to know

Answer each one before you reveal it.

Your recallNot started
Key term

Why does shaking trigger landslides?

Key term

Which slope conditions make earthquake landslides most likely?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    Why does shaking trigger landslides?

    Model answer

    The ground acceleration adds a horizontal force to the slope and momentarily reduces the friction holding the material in place, so the shear stress exceeds the shear strength and the slope fails.

  2. 2

    Which slope conditions make earthquake landslides most likely?

    Model answer

    Steep slopes of weathered rock or loose regolith, especially where they are already saturated by heavy rain.

  3. 3

    Why can landslides kill more people than the shaking itself in mountainous regions?

    Model answer

    Settlements are confined to valley floors beneath unstable slopes, so a landslide can bury a whole village in seconds and cut the roads needed to reach it.

  4. 4

    What happened in Sichuan, China, in 2008 that illustrates the landslide hazard?

    Model answer

    A magnitude 7.9 earthquake set off tens of thousands of landslides across the mountains, burying settlements, blocking roads and damming rivers.

  5. 5

    What is a landslide dam, and why is it dangerous?

    Model answer

    A barrier of debris that blocks a river and impounds a lake behind it; the loose dam can fail suddenly and release a destructive flood downstream.

  6. 6

    How are landslide dams usually made safe?

    Model answer

    Engineers cut a controlled spillway across the debris so that the lake drains steadily instead of bursting through.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.

1Closed book
2Open book
3Closed book

The 3-step method, run for you

Answer cold, learn it, then prove it stuck. Levo tracks the jump between your first attempt and your last.

Coastal Landscapes
Glaciated Landscapes
Dryland Landscapes
Earth’s Life Support Systems

Cram a whole paper in one sitting

Sort every topic into what you know and what you do not, then drill only the weak ones.

Hotter magma is .
runnierthickerslower

Blank Blitz makes facts automatic

Rapid timed gap-fills on the terms and numbers you need to recall without thinking.

AThe lower quartile is the 2nd value, 11 cm.
BThe upper quartile is the 6th value, 16 cm.
CThe interquartile range is 16 − 11 = 5 cm.

Build It gets the exam shape right

Assemble a full-mark answer from its marking points, in the order an examiner wants them.

The sunspot cycle lasts about 11 years.
TrueFalse

Test It catches misconceptions

Spot the fault in a statement. The traps are the mistakes students actually make.

721941163128510

Brain Breaks between sessions

Short focus games to reset attention, so the next set lands better than the last.

Every question in Hazardous Earth, on a schedule.

Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.

Or £46 a year, about £3.83 a month. Cancel anytime.