Science 10: Lesson 3 Volcanic Hot Spots (Part 3)

Summary

In this science lesson, Marian Soriano introduces students to the concept of volcanic hot spots, explaining that not all volcanoes are near plate boundaries. Hot spots, like those in Hawaii, form due to intraplate activity and mantle plumes. The Hawaiian Islands serve as a prime example, showing how volcanic island chains are created and how plate movement affects their activity. Students are engaged in an activity to identify the oldest and youngest islands and the direction of plate movement, concluding with the understanding that hot spot volcanoes are distinct from those at plate boundaries.

Takeaways

• 🌋 Active volcanoes are not only found near plate boundaries but can also exist in the middle of a plate, like the Hawaiian Islands.
• 🔥 Volcanic hot spots are areas of geologic activity that occur within a plate, caused by a mantle plume which brings magma up to the surface.
• 🌍 The movement of tectonic plates carries islands away from a hot spot, creating a chain of volcanic islands and seamounts, as seen in the Pacific Ocean.
• 🏝️ The Hawaiian Islands are a prime example of a hotspot volcanic chain, with the direction of plate movement indicated by the progression of the islands.
• 📉 Older islands in a hotspot chain are farther from the hot spot and tend to be less active, while younger islands are more active and closer to the hot spot.
• 🚫 Hot spots are more common beneath oceanic crust because it is thinner than continental crust, allowing for easier penetration by magma plumes.
• 🌆 Yellowstone is an example of a volcanic hot spot within continental crust, responsible for significant volcanic activity in North America.
• 📝 Students are encouraged to engage with the material by studying the Hawaiian Islands and answering activity questions about the islands' age, activity, and plate movement.
• 📉 Kauai is identified as the oldest island in the Hawaiian chain, while Hawaii is the youngest and most active.
• ➡️ The direction of plate movement can be deduced from the arrangement of the Hawaiian Islands, moving from Hawaii to Kauai.
• 🔥 The molten material in a hot spot is called magma, which is responsible for the formation of volcanic islands.

Q & A

What is the main focus of the science lesson presented by Marian Soriano?

The main focus of the lesson is to explain the concept of volcanic hot spots and how they are responsible for the formation of certain volcanic islands, particularly the Hawaiian Islands.

Why are most active volcanoes found near plate boundaries?

Most active volcanoes are found near plate boundaries because of the tectonic activity that occurs there, which allows magma to rise to the surface and form volcanoes.

What is a volcanic hot spot and how does it differ from a typical volcano found at plate boundaries?

A volcanic hot spot is an area within a tectonic plate where there is a source of molten material from the mantle, called a mantle plume, that forms volcanoes. Unlike typical volcanoes at plate boundaries, hot spots are not directly related to the movement of tectonic plates.

What is the term used to describe the geological activity that occurs within a plate rather than at its boundaries?

The term used to describe this type of geological activity is 'intraplate activity'.

How do volcanic hot spots contribute to the formation of volcanic island chains?

Volcanic hot spots contribute to the formation of volcanic island chains by remaining stationary while the tectonic plate moves over them, creating a line of volcanic islands as new islands form over the hot spot and older ones move away and become extinct.

Which island in the Hawaiian chain is considered the oldest based on the script?

Kauai is considered the oldest island in the Hawaiian chain because it is the farthest from the hot spot.

Which island in the Hawaiian chain is the youngest and why?

The youngest island is Hawaii because it is located directly above the hot spot, where the most recent volcanic activity is occurring.

What is the least active volcano among the Hawaiian islands according to the script?

The least active volcano is on the island of Kauai, as it is the oldest and furthest from the hot spot.

What is the most active volcano among the Hawaiian islands?

The most active volcano is on the island of Hawaii, as it is situated above the hot spot where magma is readily available.

How can the direction of plate movement be determined from the Hawaiian Islands?

The direction of plate movement can be determined by observing the chain of islands, with the oldest at one end and the youngest at the other, indicating the direction from where the plate has moved over the hot spot.

What is the molten material found in a hot spot called?

The molten material found in a hot spot is called magma.

Why are hot spots more common beneath oceanic crust than continental crust?

Hot spots are more common beneath oceanic crust because it is thinner than continental crust, allowing the magma plume to more easily penetrate and create a hot spot.

What is a notable example of a volcanic hot spot found in continental crust?

Yellowstone is a notable example of a volcanic hot spot found in the continental crust of the North American plate.