The Ancient Island That Transformed Washington: A SciShow Field Trip #2

The video explores the geology of Olympic National Park, focusing on the presence of basalt despite the absence of volcanoes. It explains the story of Seletzia, a volcanic island that collided with North America 50 million years ago, leading to the basalt found in the region. The video discusses geological evidence and hypotheses about Seletzia's origin, including the role of the Yellowstone hotspot. The narrative highlights the importance of understanding geological history to appreciate the landscape.

What is the primary reason for the presence of basalt on the Olympic Peninsula?

• Erosion of nearby mountains

• A volcanic island called Seletzia collided with North America

• Volcanic eruptions from the Cascades

• Basalt was transported by glaciers

Why did Seletzia not subduct under the North American plate?

• It was too hot and buoyant

• It was too cold and dense

• It was moving too fast

• It was protected by a tectonic shield

What evidence supports the theory of Seletzia's accretion onto North America?

• Presence of granite in the region

• Discovery of ancient fossils

• Seletzia basalt stretches from Oregon to British Columbia

• Frequent volcanic eruptions in the area

What is the hypothesized origin of the volcanic island Seletzia?

• Formed by the Yellowstone hotspot

• Emerged from the ocean floor spontaneously

• Created by a meteor impact

• Result of a massive earthquake

What is a debated hypothesis about the formation of Seletzia?

• It was a result of a volcanic eruption in the Cascades

• It was formed by the collision of two tectonic plates

• It was created by the Yellowstone hotspot

• It was formed by the movement of glaciers