Question

At which type of plate boundary do tectonic plates slide past each other? Why were the fossil remains of Mesosaurus important to Alfred Wegener? Which best describes paleomagnetism? Geologists discovered that the largest coal deposits were formed around 300 million years ago. How did this observation support the theory of plate tectonics? Where would you be most likely to find the oldest rocks on Earth? Which of the following provides evidence that South America, Africa, Antarctica, and Australia were once together as one supercontinent? Select the three correct answers. Geologists discovered fossils of identical spider mites from the same period but on opposite sides of the ocean from each other. What conclusion is supported by the discovery of these fossils?

Answer 1

1. At which type of plate boundary do tectonic plates slide past each other?

   • Tectonic plates slide past each other at transform boundaries.

2. Why were the fossil remains of Mesosaurus important to Alfred Wegener?

   • The fossil remains of Mesosaurus were important to Alfred Wegener because they provided evidence for his theory of continental drift. Since Mesosaurus was a freshwater reptile whose fossils were found in both South America and Africa, this suggested that these continents were once joined together, allowing the species to inhabit both regions.

3. Which best describes paleomagnetism?

   • Paleomagnetism is the study of the record of Earth's magnetic field in rocks, sediment, or archeological materials. It involves examining the orientation of magnetic minerals in rocks, which can indicate the historical positions of tectonic plates.

4. Geologists discovered that the largest coal deposits were formed around 300 million years ago. How did this observation support the theory of plate tectonics?

   • The observation supports the theory of plate tectonics because coal deposits are typically formed in warm, swampy environments found near the equator. The presence of such deposits in areas that are now far from the equator indicates that these landmasses, which are now in different climatic zones, were once located near the equator when the coal was formed, demonstrating the movement of continents over geological time.

5. Where would you be most likely to find the oldest rocks on Earth?

   • You would be most likely to find the oldest rocks on Earth in continental shields or cratons, specifically in regions such as the Canadian Shield, where Precambrian rocks, some over 4 billion years old, are exposed.

6. Which of the following provides evidence that South America, Africa, Antarctica, and Australia were once together as one supercontinent? Select the three correct answers.

   • The three pieces of evidence often cited include:
     • Similar geological formations and mountain ranges on these continents (e.g., the Appalachian Mountains in North America and the Caledonian Mountains in Scotland).
     • The distribution of identical fossil species across these continents (e.g., Mesosaurus and Glossopteris).
     • Similarities in the shapes of the continents that suggest they fit together like pieces of a jigsaw puzzle.

7. Geologists discovered fossils of identical spider mites from the same period but on opposite sides of the ocean from each other. What conclusion is supported by the discovery of these fossils?

   • The discovery of identical spider mites from the same period on opposite sides of the ocean supports the conclusion that these continents were once connected, allowing for the migration of species before the continents drifted apart. This finding provides additional evidence for the theory of continental drift and plate tectonics.