Exploring mud volcanoes
We've finally left West Flower Garden Bank and cruised east toward a flat muddy plain. In the center of the plain are some curious structures called mud volcanoes. Now, I'll let the scientists tell you all about how mud volcanoes form and why they are there. However I will tell you a couple of things I do know. They aren't hot. That's because they aren't receiving heat energy from deep in the earth like normal volcanoes. But they do look and act a lot like normal volcanoes otherwise.
While Carolyn and Argus investigated a volcano to the north, NR-1 descended on top of what we thought were extinct mud volcanoes. We imaged it first with our side scanning sonar and found a large crater about 50 yards across on the summit. The summit was about 160 feet up from the surrounding plane. On the sonar images we could see a wisp of something trailing off the top of the mound.
We thrusted the submarine down on top of the hill and crept toward the center and, "Eureka!" we found that the dormant volcano was highly active, with a constant jet of gas, brine and silt being ejected from a briny mud pool inside the crater. The rocky structure inside the crater was jagged and run through with small canyons where dense brine seeped out. Our science riders, Mark and Doug, were completely beside themselves. Mark asked me if we could get a mud sample from the pool, but I unhesitatingly said, "NO!" because the ground was too unstable.
We filmed the gas jet with all our forward cameras and made some more passes over the volcano to obtain some more sonar images. Then we called Carolyn and Argus over to share in the fun. Hopefully you got to see the volcano live on the internet!
Next we explored one of the really extinct volcanoes. It had a big flat top and a fringe of reef rocks around the edges, lots more fish and more devoloped coral. Tomorrow we surface again to bring on some more riders.