Science Olympiad Dynamic Planet Practice Test

What is an example of an above sea-level mid-oceanic ridge?

1. Iceland

2. The Mariana Trench

3. The Pacific Ring of Fire

4. The Himalayan Range

The correct answer is: Iceland

Iceland is a prime example of an above sea-level mid-oceanic ridge due to its unique geological features that arise from its location on the Mid-Atlantic Ridge. The Mid-Atlantic Ridge is a divergent tectonic plate boundary where the Eurasian Plate and the North American Plate are moving apart. As the plates separate, magma from the Earth's mantle rises to fill the gap, creating new oceanic crust. In the case of Iceland, this process has pushed up land above sea level, resulting in an island that features the ridge's characteristics, including volcanic activity and geological formations typical of rift zones. The volcanic activity on Iceland is due to the melting of the mantle as the plates are pulled apart, which allows for the formation of new land and geothermal features. In contrast, areas like the Mariana Trench are underwater and represent the deepest parts of the ocean, not ridges. The Pacific Ring of Fire is a region characterized by frequent earthquakes and volcanic activity due to plate tectonics, but it is not a specific mid-oceanic ridge that is above sea level. Lastly, while the Himalayan Range is a significant mountain range, it is created by the collision of tectonic plates, rather than the rifting and upwelling associated