HOT SPOTS

Based on material from Volcano World.

Coincidence??? A geologist in the

1960's noticed that there were chains of volcanic islands in the Pacific Ocean that ran in lines parallel to each other.

The active (youngest) volcanoes in these chains are all located in the southeast corner and are the last island in that group.

The oldest islands were the most northwestern islands in the group.

Based on material from Volcano World.

Three Hot SpotsTuzo Wilson decided that the Pacific plate was moving over three hot spots. Each groups of islands had formed over a different hot spot.

About 43 million years ago the Pacific plate shifted to a more northwesterly direction and all the island groups changed course at the same time!!

Based on material from Volcano World.

Mantle PlumesA hot spot occurs because of the intense heat the outer core radiates through the mantle bringing hot solid rock upward.

These areas of rising solid rock are called mantle plumes.

Most hot spots are located at mid-ocean ridges, but there are a few located in the middle of plates, like Hawaii and Yellowstone.

Based on material from Volcano World.

Hawaii4.6 million years ago there was only one island in this group. As the Pacific plate moved slowly toward the northwest, it produced the Hawaiian Islands, one at a time. Today the big island of Hawaii sits over the same hot spot that produced the other islands.

Based on material from Volcano World.

KauaiThe first Hawaiian Island to form over the hot spot was Kauai. It began to break the surface of the Pacific Ocean about 4.6 million years ago.

Based on material from Volcano World.

OahuAs the Pacific plate moved westward, the island of Oahu formed.

The capital and largest city of Hawaii, Honolulu, is located on this extinct volcanic island.

Based on material from Volcano World.

Oahu, Molokai, Lanai, and Maui

The islands of Oahu, Molokai, Lanai, and Maui all share the same volcanic base.

They all formed from separate volcanoes that were connected by huge lava flows.

These volcanic islands formed from the same hot spot.

Based on material from Volcano World.

Hawaii & the Mauna Loa Volcano

Today the Big Island of

Hawaii sits over the hot spot. Konala, Hualaiai, Mauna Kea, Mauna Loa and Kilauea volcanoes have built the island over the last 500,000 years.

Mauna Loa Volcano is the largest volcano on Earth. It is over 30,000 feet tall from the seafloor where it was born to the summit, which is 13,684 feet above sea level.

Based on material from Volcano World.

Hot Spots Animation

The EndAnswer these questions on the back of your handout.

(1) What moves? The Pacific Plate or the Mantle Plume?

(2) What doesn’t move? The Pacific Plate or the Mantle Plume?

(3) What direction is the movement?(4) What causes Hot Spots?