Howdy! I’m Justin Estep and am just starting as a PhD student at Texas A&M. I’ll be working under Dr. Bobby Reece, our chief scientist for this project. As we transit across the ocean, I want to take the time to explain the scientific questions that act as the motivation behind this expedition.
Our objective is to collect information on how oceanic crust changes with age using seismic reflection and refraction data. Seismic waves (essentially sound waves) travel through the subsurface bouncing and bending before returning to our instruments. We can use these waves to image the structure of Earth’s rocky outer layer that we call home, known as the crust. There are two types of crust: continental crust makes up the planet’s continents and oceanic crust lies under the oceans. Beneath the surface of the ocean there is a large network of volcanic mountains where magma is welling up from deep in the earth to produce new crust; in the Atlantic Ocean we call the mountain chain the Mid-Atlantic Ridge (MAR). From the MAR, the crust spreads away from ridge and gets older in each direction. For our expedition, we will begin collecting data at the Mid-Atlantic Ridge where we will be looking at brand new crust. From the ridge, we will travel west 1500 kilometers collecting data from crust that gets progressively older. After we have finished we will have a continuous dataset from ocean crust that ranges from brand new all the way to ocean crust that formed when the dinosaurs walked the earth, about 70 million years ago. This will be the longest continuous transect of seismic data from oceanic crust ever collected! With the data we are going to collect, we hope to learn more about the structure and processes taking place deep inside the planet.
I hope this has helped clarify why we are out here a little. Stay tuned because in the near future we will be going into more detail on those crustal changes we expect to see and the methods we are using to collect seismic data. We are only a couple days away from beginning equipment deployment and data collection!