Question 1 Report
The table below shows observations from a visitor centre on the flank of Mount Etna, Italy. Fig. 1 shows a cross-section through the volcano, including a lava flow channel and a road used by nearby villages. Rangers closed the road after changes were seen at the crater. The study figure helps visitors understand that volcanic hazards can differ greatly in speed and danger.
| Observation day | Number of volcanic earthquakes | Sulfur dioxide output (tonnes per day) | Lava-flow speed (m per hour) |
|---|---|---|---|
| Monday | 26 | 840 | 0 |
| Wednesday | 79 | 1460 | 12 |
| Friday | 134 | 2210 | 37 |
(a) Which observation gives evidence that the eruption was intensifying between Monday and Friday? [2]
(b) Draw an annotated sketch showing how lava flows could threaten the road and settlement in Fig. 1. [4]
(a) Any valid comparison: volcanic earthquakes rose from 26 to 134 [1]; sulfur dioxide output rose from 840 to 2210 tonnes per day / lava speed rose from 0 to 37 m per hour [1]. [2] (b) Four annotations, one mark each: lava emerges from crater / vent [1]; gravity carries lava downslope [1]; lava follows the valley / flow channel [1]; road can be cut off [1]; homes or farmland may burn / be buried [1]; evacuation route may be blocked [1]. [4]
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