Study Fig. 3, which shows the depth of focus and magnitude of major earthquakes in Indonesia during a month in 2009. [Figure 3]

1. (a)(i)What was the depth of focus of the deepest earthquake during this period? ........................................................... kilometres[1]
2. (a)(ii)What was the magnitude of the most severe earthquake during this period?[1]
3. (a)(iii)Complete the following sentence. Most of the earthquakes were at a depth of between ................................... and ................................... kilometres and were between ................................... and ................................... in magnitude.[2]
4. (a)(iv)Tick the correct statement about the earthquakes in the table below. There is a strong positive relationship between magnitude and depth There is a strong negative relationship between magnitude and depth There is no relationship between magnitude and depth[1]
5. (b)Explain why earthquakes occur at subduction zones, such as in Indonesia. You may draw a labelled diagram as part of your answer.[3]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.