Woods Hole Oceanographic Institution

Author Archive for Kristen Fauria

Student art visits the seafloor

Before the cruise, several science team members visited K-12 classrooms to talk about ocean science and what our jobs are like as scientists. We brought styrofoam cups to the classrooms and the students inscribed and bedecked cups with art and messages. Their cups are here with us on the MESH cruise and we used Jason and the elevator to send each cup to the seafloor.

Over 125 K-12 students decorated cups. We’ve been impressed with the creativity and diversity of student art. Some of our favorite styrofoam cup quotes are: 

Windows is better than mac

Dear volcano, please don’t blow my cup to pieces, it would make me very sad

I am going to the bottom of the ocean

You never know what’s out there until you go 

Decorating styrofoam cups is also a very popular activity with the science team during break time. Tables full of research papers, maps, delicate deep-water hardware, and coffee brewing equipment have to share space with Sharpie markers and styrofoam.

Why do we decorate? Because sending colored cups to the bottom of the ocean with Jason is incredibly fun! Styrofoam has a lot of void space, gaps that make it very light relative to its size. When you subject the cups to the high pressures in the ocean, those little pockets of air are squeezed by pressure and shrink like popped balloons. The cups don’t bounce back – they deform irreversibly. So when they come back up, you’ve got a tiny cup.

After the trip, the miniature cups will be returned to their student creators. It’s fun to let students create their own artwork and shrink it to learn about how pressure changes with depth. The cups also serve as a reminder that in a couple years, the students can be with us here too, investigating the unknown places and processes on Earth.

By Warren McKenzie and Kristen Fauria

Hydrothermal vents

Hydrothermal vents are places where hot water or steam comes out at the Earth’s surface. On land, hydrothermal vents are important for recreation and for power generation. They also tell us about what is happening beneath Earth’s surface and indicate the presence of excess heat.

If you could take an elevator ride into the Earth, you would find that temperature increases about 25 degrees Celsius per kilometer (100 degrees Fahrenheit per mile). This change in temperature, or geothermal gradient, is normal and is primarily a result of the Earth’s continuous generation of heat from radioactive decay and the way heat diffuses slowly through the Earth’s brittle crust.

A hydrothermal vent, whether on land or under the ocean, means that something out of the ordinary is bringing heat close to the Earth’s surface. Often the cause is a cooling magma that has been injected into the Earth’s crust. While the magma may stay and solidify underground, heat from the magma can reach the Earth’s surface. Hot rock or magma warms nearby ground water, making the groundwater buoyant so that it flows up through cracks and little spaces within the rocks. When the hot water or steam reaches the surface, boom – a hydrothermal vent forms.

At Havre we’ve found several hydrothermal vents. We identify them by measuring temperature with a heat probe and observing temperature gradients that exceed the geothermal gradient. The presence of vents shows that there is still excess heat underground – possibly from cooling magma that was not erupted in 2012.

The seafloor here is not lifeless. Bacterial mats flourish around the vents we see at Havre. It might be surprising that life thrives in such deep, dark places, but hydrothermal vents bring dissolved minerals to the ocean bottom – the minerals are food for these deep water ecosystems! Life may have begun at the bottom of the ocean near a hydrothermal vent – a place where the interior and exterior of our planet are directly linked.

Chimlets2

Vent2

Launching Jason

This evening, at about 4:30 p.m. local time, the Jason Team launched Jason for the first time on this cruise. This remotely operated underwater vehicle will allow us to explore the seafloor and collect samples while we watch from the surface. More than a dozen scientists, engineers, technicians, and support staff make up the Jason Team and specialize in maintenance and operation of the vehicle. The team is based at the WHOI, but travels with Jason on expeditions around the world. Read more about the vehicle here and watch the vehicle being launched below.

 

The science team is extremely excited to see what Jason discovers and as it explores Havre’s caldera. Will it find obsidian, pumice, coherent lava bodies, hydrothermal vents, pyroclastic flow deposits, all of the above, or something entirely unexpected? We don’t know.

We do know that the types of rocks and deposits we find will not only tell us about the eruption that occurred here at Havre in 2012, but will also teach us about how volcanoes erupt underwater and why they sometimes erupt explosively. Until three years ago no one had seen an eruption like Havre 2012. Until now, no one has observed or made quantitative measurements of recent deposits from a deep, explosive submarine eruption. As a result, some very basic science questions have yet to be answered, despite the fact that the vast majority of volcanic activity on Earth occurring underwater

As I type Jason is descending descends to Havre’s caldera 1600 meters (1 mile) beneath the surface on the seafloor. In a few hours we may start making our first discoveries. A lot of effort and expertise from dozens of people and institutions has made this expedition possible, and to make the most of our resources, the science and Jason teams will be operating the vehicle around-the-clock.

The rock samples and observations from the Jason dives will be the first of their kind, and the data we collect may very well spawn new models for submarine volcanism and (at least this blogger believes) stand as lasting and substantial contributions to planetary volcanology.

We are nearing the bottom now and I can’t wait to get started.