How did Devils Tower form from a liquid?

Question

Select observations that would convince someone your claim is correct.

Answer 1

Devils Tower, located in Wyoming, is an iconic geological formation that is believed to have formed from the solidification of magma beneath the Earth's surface. Here are some observations and evidence that support the claim of its formation from liquid magma:

1. Geological Structure: Devils Tower is a monolith, composed of columns of igneous rock. The distinctive vertical columns are formed as the magma cools and contracts, creating hexagonal or polygonal shapes typical of columnar jointing.

2. Igneous Rock Composition: The tower is primarily composed of phonolite porphyry, a type of igneous rock. This composition indicates that it originated from molten rock (magma) that cooled and solidified.

3. Surrounding Erosion: The surrounding area is characterized by sedimentary rock layers that have eroded away over millions of years, exposing the harder, more resistant igneous rock of Devils Tower. This suggests that the tower was once buried under many layers of sediment before being revealed through erosion.

4. Lack of Volcanic Features: Unlike a typical volcanic structure with cones and craters, Devils Tower lacks those features, indicating that it is not a volcano but rather a remnant of magma that cooled underground.

5. Field Studies and Core Samples: Geologists have conducted field studies and collected core samples that confirm the presence of igneous rock and the columnar jointing formed by the cooling process. Analysis of these samples supports the history of the area as a site of significant volcanic activity.

6. Radiometric Dating: Scientific dating methods suggest that the age of Devils Tower dates back approximately 50 million years, correlating with the period of magma intrusion during tectonic activity. This further supports the theory that the tower formed from liquid magma.

7. Comparison with Similar Formations: Other similar geological formations worldwide, such as Giant’s Causeway in Ireland and Fingal's Cave in Scotland, exhibit comparable columnar jointing, reinforcing the understanding of how such structures can form from solidified magma.

8. Visitor Interpretations and Educational Resources: The National Park Service provides educational materials that explain the geological formation of Devils Tower, which are based on rigorous scientific research.

These observations provide compelling evidence that Devils Tower formed from liquid magma that cooled and solidified underground, eventually being exposed through the processes of erosion.