1) How old is the oldest oceanic crust (Atlantic, Pacific, and Indian)? Atlantic Ocean: The oldest part of the Atlantic Ocean is near the North American and African Coasts. They are approx 180 million years old. Pacific Ocean: The oldest oceanic crust in the Pacific Ocean is closest to Japan. It is approx 155-180 million years old. Indian Ocean: The oldest oceanic crust in the Indian Ocean is to the west of Australia. It is approx 140-160 years old. 2) Approximately how old is the oceanic crust along the San Francisco coastline (continental margin)?
The crust along the San Francisco coastline is fairly new compared to other oceans. It is less than 5 million years old. 3) Where is the oldest oceanic crust located in the Pacific Ocean (generally)? Near Japan and South East Asia. 4) Where is the youngest oceanic crust located in the Pacific Ocean (generally)? Near the California coastline. 5) Describe, in general terms, the distribution pattern of youngest and oldest oceanic crust in the Pacific Ocean Basin.
The youngest crust occurs near the west coastline of North America near the North American and Juan de Fuca Plates. The oldest crust is along the Japan Trench and Marianas Trench. This is the outermost layer of the Earth. 6) Now look the Atlantic Ocean Basin, and compare the pattern of older/ youngest oceanic crust to what you say in the Pacific Ocean Basin. Are these ocean basins alike or different; could they be both? The Atlantic Ocean Basin is quite different from the Pacific. The Atlantic Basin has more activity vs the Pacific by way of plate tectonics.
There are more plate boundaries in the Atlantic, separated in the middle by the Mid Atlantic Ridge. Whereas the Pacific Basin is comprised mainly of the Pacific Plate. The Mid Atlantic Ridge is an example of a divergent plate boundary. 7) Does the spatial pattern of crustal age, as shown in this map (these maps), support the Plate Tectonics Theory? Yes it does. I can see that the oldest parts of the ocean’s crust occur along continents that would have been pieced together to make Pangaea.
Specifically, the crust is similar in age along the South America Plate and the African Plate. This supports that they were once connected. 8-9) From your reading in the textbook and the Instructor’s Notes and by looking at his map can you draw a correlation between the different topographic features you would expect to find on the ocean floor, and the age of crustal material (rock)? The ocean crust is made up mostly of basalt. Near the ocean trenches is where the oldest rock is found (McMahon, Chapter 2 Notes: Ocean’s Basins, 2013).
Closer to the coastlines and the continental shelf, one would find rock similar to what on the Earth’s continents. Further out is the ocean trenches and basins. There are series of underwater volcanoes which create “seamounts”. A seamount is an underwater eruption which resulted in an above ground island, such as Hawaii. 10) Why is there not data from the Arctic and Southern Oceans? I could not find the answer to this question, but I believe it is because of the great amount of ice around the Arctic and Antarctic regions.