From Adam to Earth Scientists in Training II
Dear Earth Scientists in Training,
Before I tell you a little more about the ship, I thought I’d show you a few things about what the IODP (Integrated Ocean Drilling Program) is all about. I think you learned a lot about this on your IODP field trip, but I’ve got a few cool pictures to show you.
WHAT IS THE INTEGRATED OCEAN DRILLING PROGRAM (IODP)? We study the past history of the Earth. We do this by taking samples (cores) of sediments from below the seafloor. The sediment that settles to the seafloor comes from a lot of different places.
Rivers carry sediment like sand and clay and pour them into the ocean. I think this is somewhat like the demonstration you gave at enrichment night- water washes sediment and chemicals into streams and lakes.
Plankton are plants and animals that live in the surface of the ocean – when they die, their bodies sink to the seafloor. Their skeletons or shells are sometimes preserved in the sediment. If there are a lot of them, then the sediment is made up of mostly plankton remains (like the samples you saw through the microscope on your IODP field trip). I’ll
show you some cool microscope pictures of the plankton later- as well as some shark and fish teeth we have found in the cores.
Sediment can be poured into the ocean by volcanic eruptions (volcanic ash) and even clay is carried by winds off of China and Russian and dropped into the Pacific (and off the Saraha Desert in North Africa into the Atlantic Ocean).
These sediments are deposited in the seafloor one layer at a time, just like a cake. The older layers are on the bottom and the younger laters are on the top. By taking cores, we
can tell what the Earth’s temperature was at that time as well as all sorts of other interesting things about the ocean currents and weather.
The oceans seafloor sediments are as old as about ~140 million years old, so we can study that much history of the Earth using the core samples we get.
HOW DOES IODP GET THE CORES OF THE SEAFLOOR? We use three ships to take cores of the seafloor.
THIS IS THE JOIDES RESOLUTION. This is the ship I’m on right now. The United States of America pays for using this ship. It has been working for us since 1985 and can
drill in almost any ocean (except for where there is ice) and at almost any water depth from 75 m to 6000 m. On this expedition, we’ve drilled one site where the seafloor
was more than 5000 m deep – that’s more than 3 miles.
This is my 13th expedition on this ship. Each one is two months long, so I’ve spent 2 years and 2 months on this ship. There are some people who work for us who have spent almost 12 years out of the last 23 years on the ship! I really love going to sea, but I couldn’t spend that much time away from my family.
THIS IS THE DRILL SHIP, CHIKYU. Chikyu is a Japanese word meaning “Earth”. Japan pays for using this ship. It is much bigger than the JOIDES Resolution – it is more like the ships and platforms that drill for oil and gas. Right now it is drilling to learn about large earthquakes where two plates collide off Japan. A lot of my friends from when I worked in Japan are running that ship. I really want to sail on it sometime!
THIS IS A PICTURE OF THE R/V ODEN AND TWO ICE BREAKING SHIPS. A group of European countries pay to run this ship and to rent other types to work in really shallow water. This picture shows the first time anyone has taken deep sea cores in the frozen Arctic Ocean. Since there is ice there almost all the time, they had to take two ice breaking ships with them to make sure they could drill and they didn’t get stuck or crushed by ice.
This was a very amazing expedition – they found times in the past when the Arctic Ocean was very warm- almost like the temperature in Texas in the summer! From the picture you can see it’s not like that now. The same European group also has taken cores off the reefs in Tahiti to look at changes in the level of the ocean. This summer, they will also drill off New Jersey as well as off the Great Barrier Reef of eastern Australia (I want to go there again! )
In my next letters, I’ll wrtie to you about who sails on The JR and the countries they’re from, and all the places across the globe where we’ve drilled.
I’m having fun, but I really miss you!
Adam