Hello all. We have one remaining type of data for which to show you some sample results: seismic reflection. Seismic reflection is the method that Justin described in an earlier post, where we use the 12 km-long streamer and sound source to image the Earth beneath the seafloor. The processing and refining of these images is quite a bit of work. We are fortunate to have the ability to work on this at sea; so we have some preliminary images to share. But I can assure you that the work will continue for months back home as we refine these images to perfection for the purposes of our research!
This sample seismic reflection profile (above) shows some of the basic features that we image in a marine survey. You can see the seafloor, as well as the crust-mantle boundary (moho), which is about 6 km below the seafloor. The white above the seafloor is the water column (ocean) which we cut out of our final images.
This zoom above from the first profile shows layers of sediment draping over the volcanic ocean crust. Since this site is not close to land, all of the sediment is pelagic, which means it has rained out from the ocean above over the last 60 million years!
The seismic profile above shows a region where the topography of the crust is more variable, so the sediments pond in basins, and portions of the crust jut out into the ocean like mountains. The crust contains quite a bit of ‘reflectivity,’ which shows structure left from when the crust was formed at the Mid Atlantic Ridge.
I hope you enjoy this preview of the data!