26. Uulu ybu expect to see a shield volcano? a. Hot spot in the ocean b. Ocean-C

Question

26.

Uulu ybu expect to see a shield volcano? a. Hot spot in the ocean b. Ocean-Continent convergent plate boundary c. Continent-Continent convergent plate boundary d. Transform plate boundary e. Any of these t St Helens is on a convergent boundary. What can we determine about its eruptions? a. they occur once every 2,000 years b. they occur predictably c. they are explosive d. they are peaceful e. a and c 28. At an ocean-continent convergent boundary, there are volcanoes because a. the magma fills in the big crack between the plates b. the subducting ocean plate melts c. as the plates move side-by-side, the magma wells up through the faults d. A and B e. B and C 29. At a hot spot, there are volcanoes because a. the magma fills in the big crack between the plates b. the subducting ocean plate melts c. as the plates move side-by-side, the magma wells up through the faults d. an area of higher temperature allows melting to occur

Explanation / Answer

26.a) Hot spot in ocean.

Explanation: Shield volcanoes volcanoes which have very gentle slopes. Such volcanoes can be formed only when the lava is less viscous .i.e the lava should be basaltic in composition. Out of the above options hot spot in ocean is the only option where basaltic magmas are generated in huge volumes. In ocean-continent mostly andestic magmas are generated while in continent-continent silicic magmas are generated.

27. c)Eruptions at Mt.St Helens are explosive.

Explanation: Mt. St Helens is a ocean continent convergent boundry. Magmas generated due to the partial melting of the crust are andesitic to silicic in nature. They are more viscous. Viscous magma eruptions are explosive.

28. b) the subducting ocean plate melts

Explanation: Partial melting of the oceanic crust generates melts.

29) d) and area of higher temperature allows melting to occur.

Explanation: Hot spots are locations where the temperature in the mantle and the area above it is higher this increase in temperature results in higher amount of partial melting. generating hot spot magmatism.

IF YOU FOUND THE ANSWER HELPFUL, A THUMBS UP WOULD BE APPRECIATED!!!

Related Questions

Navigate

• Browse (All)
• Browse 2
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.