1. Enquiry Q1: What are tectonic hazards and what causes them?
Sunday, 24 February 2019
Enquiry Q1: What are tectonic hazards and what causes them?
Learning Objectives:
To understand what makes tectonic activity hazardous.
To know the range of hazards associated with a range of tectonic activity.
To be able to create an event profile for hazards.
Key terms:
Lava
Lahar
Richter Scale
Pyroclastic flow
Liquefaction
Seismologist

2. Homework 9/09/2014 due 16/09/2014 Enquiry question 1:
What are tectonic hazards and what causes them?
Find the difference between a tectonic event, a hazard and a disaster.
Why are some tectonic activities more hazardous than others?
Find 2 case studies of recent ish (10 years) hazards, one very hazardous, one not very hazardous. Explore the reasons why. Use as many specific examples as possible within the case studies for example, number of deaths, economic losses etc.
Organise your notes so that you have areas for Unit 4 and the 4 enquiry questions within it – look at the specification for the Qs.
Make a sheet where you will keep small notes about your case studies and which enquiry question they relate to, then a section with longer notes about the specific case study.

4. HAZARDS vs DISASTERS? What is the difference?
TECTONIC HAZARD = potential to cause harm
NATURAL DISASTER = ONLY occur when the hazard results in a significant impact on people/infrastructure

5. Non-lethal Hazards Earth-building process (Constructive/Collision)
CONSTRUCTIVE = “new” land (ICELAND etc.)
THINK: how do hazards become disaster?

6. Associated Hazards...
We are going to make mind maps of potential hazards associated with these events.
EARTHQUAKES
VOLCANOES
You have been given a piece of A3 paper for each hazard and pictures of each hazard. Work together to put them in the correct places. Make notes next to each picture.

7. Impact of Earthquakes... PAGE 243 PA Ground shaking Tsunamis
Displacement
Landslides
liquefaction
PAGE 243 PA

8. Ground Displacement

9. Landslides

10. Liquefaction

11. Tsunamis

12. Impact of Volcanoes... PAGE 243 PA Lava Pyroclasts Lahars
Pyroclastic Flows
Lahars
Volcanic Gases
PAGE 243 PA

13. Primary Volcanic Hazards
Lava flow

14. Pyroclastc Flow

15. Ash and Tephra

16. Volcanic Gases
Lake Nyos, Cameroon dead

17. Secondary Hazards
Volcanic Landslide

18. Lahar

19. Tsunami

21. When is a hazard a disaster?

22. Event Profiles

23. Homework feedback
Sharing of case studies will be really useful for this unit. Each of you will discuss your homework for us all to learn.

25. How do we use this to determine how disastrous a hazard is?
Physical Exposure to hazard (RISK)
Human vulnerability to disaster (insecurity)

26. Must contain info about...
FREQUENCY – how often
MAGNITUDE – how strong
DURATION – how long
AERIAL EXTENT – how far

27. Event profiles Not all tectonic hazards are the same
Event profiles are a common way of comparing different hazards
In this example the 2004 Asian Tsunami and ongoing eruption of Kilauea on Hawaii are compared
Hazard profiles can be drawn for any event.

28. Earthquakes as hazards!
We use the Richter scale to report the magnitude of earthquakes. It is calculated from the amplitude (not the strength) of the largest seismic wave recorded.
The other option – Mercalli scale.
This measures the intensity of the earthquake.
It quantifies the effects on the Earth’s surface, humans, natural and manmade structures on a scale from I (weak) to XII (complete destruction)
Remember – Richter Scale is LOGARITHMIC
(magnitude increases ten fold!)

29. Volcanoes as Hazards

30. Volcano Explosivity Index (VEI)
Every year about 60 volcanoes erupt, but most of the activity is pretty weak. How do volcanologists measure how big an eruption is? There is not any single feature that determines the "bigness", but the following eruption magnitude scale - called the Volcanic Explosivity Index or VEI - is based on a number of things that can be observed during an eruption. According to this scale, really huge eruptions don't happen very often, luckily!

31. VEI Description Volume m/Km3 How Often Example non-explosive 1000’s m
non-explosive
1000’s m
Daily
Kilauea 1
gentle
10,000s
Stromboli 2
explosive
1,000,000s
Weekly
Etna 3
severe
10,000,000s
Yearly
Unzen Japan 4
cataclysmic
100,000,000
10’s of years
Tual P/pines 5
paroxysmal
1km3
100’s
St Helens 6
colossal
10s km3
Krakatau 7
super-colossal
100s km3
1000’s
Tambora 8
mega-colossal
1,000km3
10,000
Toba
Print for students

33. Homework 16/09/14 DUE 23/09/14
Choose two APPROPRIATE case studies for your chosen Tectonic Hazard.
Complete the sheet given (and on website) for each.
Make an event profile for your two hazards.
Find out what EM-DAT is and how it works.
Complete your mind-maps for the hazards of earthquakes and volcanoes.