By Virginia Edgcomb Ph.D., microbiologist and Associate Scientist, Woods Hole Oceanographic Institution, Life Science teacher, Falmouth Academy
(All photos by William Crawford)
Hello from the JOIDES Resolution, the U.S. drill ship! The name stands for Joint Oceanographic Institutions for Deep Earth Sampling, but is commonly known as the ‘JR.’
This ship has traveled the world’s oceans in support of the International Ocean Discovery Program’s objectives of exploring the seafloor to learn about Earth’s geological history, sub-seafloor resources, the deep biosphere, and processes such as plate tectonics.
We are out here for two months in the Indian Ocean at a remote location called Atlantis Bank, a slow-spreading ocean ridge system where the ocean crust (as opposed to continental crust that we live on) has lifted along a fault and is exposed, and is not covered with sediments. It sort of bulges, placing it closer to the ocean surface (approximately 700 meter water depth). This makes drilling the deep ocean crust easier because it is a shorter distance to the seafloor.
The overall aim of this Expedition 360 is to drill as deep as we can toward the Earth’s crust/mantle boundary. Very little is known about the deep ocean crust or about the nature of the crust/mantle boundary. There are 122 people on board, 26 of whom are scientists, mostly geologists. I’m learning a lot about geology of the ocean crust!
This expedition includes as one of its primary objectives, to determine the microbiology of the lower crust, addressing the question: What are the limits of life in the sub seafloor?
This is where I come in.
Dr. Edgcomb selects a sample for microbiology analysis from one of the core sections with Chris Macleod, one of the chief scientists on this cruise.
I am one of two microbiologists on this ship. When sections of core come up on deck every four hours or so, I process a sample of that rock each time for analyses of DNA, RNA, lipids, carbon isotopes, exoenzymes, ATP, cell counts, and microscopy, and I take some of the crushed rock material and start enrichment cultures for Bacteria, Archaea, and Fungi.
This work is really exciting because we are hoping to find evidence in this type of crustal rocks for microorganisms that can obtain their carbon and energy from molecules that can be produced entirely from the rocks themselves, when certain minerals interact under the right conditions with warm water!
There is an energetic education and outreach team on board with us, and they’ve been meeting via live video Zoom meetings with school groups, university groups, and museums throughout the cruise to show students around the ship and to let them meet some of the scientists involved, see them working, and ask questions.
I’m very excited because Ms. Liz Klein’s Earth Science class at Falmouth Academy joined us live, and I got to see some of my old students! Connecting students with my own research, particularly during fieldwork like this, is one of the most rewarding parts of being a teacher at Falmouth Academy.
Science is not just a bunch of facts we already know, it’s a field of exploration that allows us to learn more about the world we live in and how it works. Much to my own enjoyment, many of my Falmouth Academy students end up conducting Science Fair projects in my laboratory or someone else’s at the Woods Hole Oceanographic Institution, expressing interest in one of the science internship opportunities that we offer, and in some cases, they end up working in my laboratory at WHOI during summers. Quite a few former students have gone on to pursue undergraduate and graduate studies in science.
Virginia Edgcomb, Ph.D., is an Associate Scientist in the Department of Geology and Geophysics at the Woods Hole Oceanographic Institution. She studies the diversity and adaptations of protists and other members of microbial communities in oxygen-depleted and extreme marine environments and has received The International Society of Protistologists’ Seymour Hutner Award and is currently President of that society. She also helped design a robotic instrument that collects, incubates, and preserves microbes in the deep ocean. Dr. Edgcomb is currently a member of a two-month expedition to delve deeply into the earth’s ocean crust in the Indian Ocean.