How do we know what the seafloor looks like? Remotely operated submersible vehicles are often employed to map and explore the seafloor, especially in places divers could not get to for safety and/or logistical reasons. The following video explains how SCINI, a robotic explorer, allows scientists to study the seafloor in deeper waters near Antarctica.


Another technology used to explore the seafloor is sonar. Sonar, which stands for sound navigation and ranging, works by emitting pulses of sound waves from a ship, which bounce off any objects they hit and return to their source. On the boat, a receiver picks up the return signals and measures the amount of time it takes for the sound waves to return. Computers analyze this information to create images of what the objects look like, its size, shape, and density. This essentially allows scientists to "see" the seafloor and map mountains, canyons, and plains on the ocean floor. The interactive lesson on the next page describes and shows how different types of sonar work.

Then, on the following page, explore the technology scientists have used to map the Arctic seafloor, including sonar and autonomous underwater vehicles (AUVs) equipped with special probes and sensors to measure chemical and physical properties of the seafloor and ocean water. Also, learn about the unique challenges of mapping and studying the oceans near the Arctic mid-ocean ridge.

Source: Teachers' Domain, Studying the Antarctic Sea Floor, published April 1, 2009, retrieved on June 19, 2010,
http://www.teachersdomain.org/resource/ipy09.sci.life.eco.scini/