Points of Light
Findings Log: 7/17/11
The area we are looking at over the past few days is a small site along the globe-encircling chain of volcanoes called the Mid-Ocean Ridge. We know there are frequent eruptions along the Mid-Ocean Ridge but we can only put a time and date on the few that we’ve serendipitously come across or monitored with fixed hydrophones (underwater microphones) in a few small areas. Sometimes we see indication of seafloor spreading events (or their immediate aftermath) by detecting the warm and turbid plumes rising up into the water column. This is what attracted us to the sites we are now exploring on the seafloor. This “seam” is where new ocean crust is “born” as molten rock intrudes in long thin dikes, spreading apart the ocean crust and often erupting onto the seafloor. The birth is accompanied by venting of nutrient rich fluids that feed a rapid growth of microbial communities followed by colonization of higher level chemosynthetic organisms such as the giant tubeworms and clams found on the Galapagos Ridge.