Question

1. what happens when lava meets the ocean?

a. it creates earthquakes
b. nothing happens
c. it turns the ocean into steam and makes new land
d. it causes tsunamis

1. what type of volcano is mount st. helens?

a. shield volcano
b. extinct volcano
c. composite cone
d. cinder cone

1. how do plants begin growing on new volcanic landscapes?

a. they are planted by humans
b. seeds are carried by wind to cracks where water collects
c. they grow only in volcanic ash
d. through underwater roots

1. what is a strata cone volcano?

a. a volcano that only produces ash
b. a combination of shield and cinder cone characteristics
c. an underwater volcano
d. a dormant volcano

1. what happens to the bottom of a caldera when the magma chamber empties immediately?

a. it explodes
b. it sinks deeper
c. it rises slightly
d. nothing changes

1. what makes some volcanoes explode while others ooze?

a. their location only
b. the presence of water and gas content
c. the time of year
d. the surrounding air temperature

Explanation:

1. When lava meets the ocean, the extreme heat causes the water to turn into steam in a process called steam - blast erosion, and over time, new land can form as the cooled lava accumulates.
2. Mount St. Helens is a composite cone (stratovolcano) which is built up by many layers of hardened lava, tephra, pumice and volcanic ash.
3. Seeds are often carried by wind to cracks in new volcanic landscapes where water can collect, allowing plants to start growing.
4. A strata cone volcano (stratovolcano) has a combination of characteristics from different types of volcanoes like shield and cinder cones, built up from alternating layers of lava flows, volcanic ash, and other volcanic debris.
5. When the magma chamber beneath a caldera empties, the bottom of the caldera sinks deeper due to the lack of support from the magma.
6. The presence of water and gas content in the magma determines whether a volcano will explode (high gas content leads to explosive eruptions) or ooze (low gas content leads to effusive eruptions).

Answer:

1. c. It turns the ocean into steam and makes new land
2. c. Composite cone
3. b. Seeds are carried by wind to cracks where water collects
4. b. A combination of shield and cinder cone characteristics
5. b. It sinks deeper
6. b. The presence of water and gas content