Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

Which type of volcano is currently erupting or building up to an eruption?

1. Extinct

2. Dormant

3. Active

4. Composite

The correct answer is: Active

The correct choice is the type of volcano that is currently erupting or building up to an eruption, which is identified as active. Active volcanoes are characterized by ongoing eruptive activity or those that show signs of potential eruption in the near future. These volcanoes are part of the dynamic processes within the Earth's crust, where magma is present and can push its way to the surface, resulting in eruptions. Active volcanoes are monitored closely by scientists looking for signs such as increased seismic activity, gas emissions, and changes in landforms, which can indicate that an eruption might happen soon. This monitoring is crucial for public safety in areas surrounding these volcanoes. In contrast, extinct volcanoes are those that have not erupted in a substantial amount of time and are not expected to erupt again. Dormant volcanoes, while currently not erupting, are still considered potentially active because they could erupt again at some point in the future. Composite volcanoes, on the other hand, refer to a specific type of volcano built from multiple layers of lava and ash, but whether they are active or not depends on their current activity status. Thus, the definition of an active volcano clearly identifies it as the type that is either erupting or showing signs of potential eruption.