After reading this chapter, you should:
- know the names and locations of the major oceans
- know the average depth of the ocean
- be able to identify the deepest region of the world ocean
- know the differences between passive and active continental margins
- know the geological features of a continental margin, and what is responsible for them
- know the various ocean provinces
- understand how oceanographers can map the seafloor
There are many reasons why people study oceanography. An understanding of ocean processes is obviously vital to oceanographers, marine biologists, or environmental scientists. However, there are numerous other scientific fields where the oceans play an important role. The oceans are a major contributor to global climate patterns, and can give us clues to past climate conditions. Knowledge of oceanography is important for resource or energy extraction, such as commercial fishing or aquaculture, oil and gas exploration, and clean energy resources such as wind, wave, or tidal energy. The oceans are the major route for international trade through commercial shipping, and are still a significant factor in the transportation of people across the seas. But even the recreational user benefits from an understanding of the ocean, from winds and currents for the casual sailor, tides and habitat conditions for a fisherman, to wave patterns for surfers. And finally, for anyone who has ever stood on the shore and gazed out at the ocean with a sense of wonder at what lies beneath the surface, the study of oceanography can begin to reveal some of the ocean’s mysteries.
This chapter begins with a basic overview of the world oceans, before discussing some of the ways that the features of the ocean can be classified. Finally, we will examine the techniques that are used, and have been used, to map the ocean floor.