Following are images taken by the ROV Argus during the Secrets of the Gulf Expedition. These images show a couple of different mud volcanos that were visited during the course of the expedition. Instead of magma, methane gas is bubbling up through the sea floor. The resulting cone of sediment resembles a volcano, hence the term "mud volcano".
Additional expedition images can be viewed at the following links:
Click on a picture below to see a larger, hi-resolution image. Credit for all of these photos goes to the Institute for Exploration and University of Rhode Island Institute for Archeological Oceanography (IFE/URIIAO).