Paleoclimatologists can’t see

Without a little geophysics that is. The ocean is a big place. How do you know where to core? Here are three sites we imaged, one of them yielded our longest core yet. Which one do you think it was? Why?


Riley posted a note about describing our faithful gravity coring rig and how it works. ┬áTo image the ocean bottom and decide were to send her down we use a sub-bottom profiler also known as chirp. It’s a nifty piece of equipment mounted on the bottom of the ship that sends an acoustic pulse (that sounds like a bird chirping) to the bottom and records the echos. With some numerical trickery (a Hilbert transform) these echos are then converted into the images you see above. These images show the very shallow structure (top 10-20m) of the ocean floor, we look at the contrast and geometry of the reflections to make inferences about what the devil is down there. Here’s another picture of the coring rig, remember it is jsut a weighted (600lbs) pipe. So, which site would you have picked?

Core rig deployed from the A-frame

Core rig deployed from the A-frame

~ Diego










Answer: Site 3