Where do earthquakes occur?

1
Where do earthquakes occur?
2
Plate Tectonics
3
The Ring of Fire
4
Earthquakes
What instrument do we use to measure earthquakes?
What do the values mean?
What scale do we use to report the magnitude of
an earthquake?
5
Earthquakes
Magnitude Average Annually
8 and higher 1 ¹
7 - 7.9 17 ²
6 - 6.9 134 ²
5 - 5.9 1319 ²
4 - 4.9 13,000(estimated)
3 - 3.9 130,000(estimated)
2 - 2.9 1,300,000(estimated)
¹ Based on observations since 1900. ² Based on observations since 1990. ¹ Based on observations since 1900. ² Based on observations since 1990.
How many Earthquakes (on average) occur on the
Earth each year?
6
Recent Earthquake in Haiti

• January 12th 2010, Magnitude 7.0 on the Richter
  Scale!!
• Lots of BIG (lt6.0) aftershocks
• Occurred 15 km below the surface of the Earth
  (why there?)

7
Recent Earthquake in Haiti
What type of fault?
8
Recent Earthquake in Haiti
230,000 Confirmed Deaths (6th deadliest
earthquake)
9

Recent Earthquakes in Chile

• February 27th 2010, Magnitude 8.8 on the Richter
  Scale!!
• Lots of BIG (lt6.5) aftershocks
• Occurred 35 km below the surface of the Earth
  (why so deep?)
• 500 people died

10
Subduction
Where do we get earthquakes? Where do we get
volcanoes?
Where do we get earthquakes? Where do we get
volcanoes?
volcanoes
CHILE
Epicenter
Focus
11
Hait vs. Chile Discussion
What are the main differences between the Haiti
and Chile Earthquakes?
Haiti
Chile
12

Earthquakes
Where was the LARGEST recorded Earthquake in the
WORLD?

13

Earthquakes
The Earthquake in 1960 in CHILE was SO BIG that
it is thought to have caused a volcano to erupt!!

Cordon Calle volcano with an eruption cloud. The
volcano, which was within 200 km (124 miles) of
the earthquake epicenter, began to erupt two days
after the earthquake.