Question

What are the four changes in a volcanic area that are monitored in order to detect the movement of magma?

a) Temperature, humidity, wind speed, and cloud cover.
b) Ground deformation, gas emissions, seismic activity, and changes in water chemistry.
c) Vegetation growth, river erosion, wildlife population, and soil composition.
d) Volcanic rock type, crater size, lava flow speed, and magma color.

Answer 1

Ground deformation, gas emissions, seismic activity, and changes in water chemistry are the four changes in a volcanic area that are monitored to detect the movement of magma.

Step-by-step explanation:

The four changes in a volcanic area that are monitored in order to detect the movement of magma are:

1. Ground deformation: This refers to the changes in the shape of the ground caused by the movement of magma beneath the surface. Instruments like GPS and tiltmeters are used to monitor these changes.
2. Gas emissions: Volcanoes release various gases, such as sulfur dioxide, carbon dioxide, and steam, during eruptions. Monitoring the types and amounts of gases being emitted can provide clues about the movement of magma.
3. Seismic activity: Volcanic activity is often accompanied by earthquakes. Seismometers are used to monitor the frequency, intensity, and location of these earthquakes, which can indicate the movement of magma.
4. Changes in water chemistry: Magma can interact with groundwater, causing changes in the chemical composition of water sources near volcanoes. Monitoring the levels of certain elements and compounds in the water can help detect the presence and movement of magma.