Activity: Plotting earthquake epicentres K 14-16

Subject: Seismology, Plate Tectonics

Objectives: In this activity students will plot worldwide earthquake epicenters to reveal the narrow zones of seismic activity on the Earth and aid in the understanding of plate tectinics

Key words:

Epicentre, focus, magnitude, latitude, longitude and Plate Tectonics

Disciplinary field: Earth Science

Procedure:

The students will plot the earthquake epicenters on a world map. This activity is designed for students to discover the patterns of earthquakes around the world and to identify locations of large earthquakes and associated geologic features.

Phase 1:

The students receive the figure 1 that represents the world map, and the list of significant earthquakes of the world in 2004 (table 1). Students plot the earthquake epicenters on the world map using latitude and longitude coordinates.

Figure 1: A world map

The table 1 reports the gather of significant earthquakes of the world in 2004, latitude and longitude coordinates to locate the epicenters on the map and the magnitude associated. The students will use 4 color pencils to plot the events by magnitude. Students must to determine the appropriate colored symbol representing the magnitude and identify the latitude and longitude points on the map. For to plot the data by magnitude, the ratios of size should be evident, as well as relationship between tectonic processes and event size. As soon the students plot the data, they observe the patterns of earthquakes, and often begin to ask a questions about interpreting the patterns.

Table 1: List of significant earthquakes of the World in 2004

This is an extract of table 1

Earthquakes of the World in 2004
DATE	UTC-TIME	COORDINATE	REGION	MAGNITUDE
GENNAIO 01	23:31:54.3	17.8N 1001.2W	MEXICO	6.0
GENNAIO 01	21:08:16.0	24.2N 78.1E	NORTHERN INDIA	5.3
GENNAIO 01	21:00:15.1	6.9S 115.9E	BALI SEA	5.8
GENNAIO 03	16:23:21.0	22.253S 169.683E	LOYALTY ISLANDS	7.1
GENNAIO 10	18:38:14.8	36.852N 3.418E	NORTHERN ALGERIA	4.5
GENNAIO 25	11:43:11.8	16.830S 174.196W	TONGA	6.7
GENNAIO 28	22:15:30.7	3.120S 127.400E	SERAM-INDONESIA	6.7

Phase 2:

The students will develop a map that can be used to introduce the concept of plate tectonics, magnitude scale and frequency of events.

Epicenter placement can be compared with geographical lacation listed on the seismic activity report. Students can use current reports of seismic events available on internet to know global seismicity. For exemple the National Earthquake Information Center’s website provides a current list of earthquakes, a maps of world seismicity and includes all the information that the students need to complete the activity.