HOW CAN A VOLCANO ERUPT COLD?
By Homer Montgomery
1228 Zulu (GMT) - R/V Melville East of Guam

I am presently on watch.On the screen in front of me is a sonar image of the Mariana Trench.We are now sailing above the deepest trench on the face of the earth.I am looking at this greatest slash in detail and in real time.Perhaps this does not strike you as all that interesting, but it sure does me.This trench is a different sort of animal than others on this planet.Other than being the deepest, it also has precious little sediment obscuring its features.I was told that if you dropped a glass bottle over the side of the ship it would take ninety minutes to hit the bottom.I believe it. Earlier today on our way into the trench we passed over a fascinating feature on the ocean floor.That is a serpentine volcano.These odd volcanoes erupt essentially cold. They are a conduit for water from the subducting slab.The erupting water contains the recipe for blueschist minerals.Blueschist minerals are characteristic of high pressure, low temperature conditions (i.e. down a subduction zone).The water is also less salty than sea water. Serpentine volcanoes have an odd range of life living on them, sort of like the black smoker communities without the black smokers.Dr. Patty Fryer is studying these things.She is not far from our position aboard the drill ship Resolution which is presently trying to drill a hole into one of these things.They hope to install a device that will allow them to repeatedly come back with the Alvin and sample the fluids, fluids that undoubtedly hold a wealth of secrets.This impresses me.This is really good science begin carried out under extreme circumstances.