Analysing the sediment cores from the RRS Discovery research vessel
Posted on: 25/08/2022 By: Jane Earland
At the beginning of July, we unloaded our sediment cores off of the RRS Discovery research vessel in Southampton and took them directly across the dockside to the British Oceanographic Sediment Core Research Facility (BOSCORF).
At BOSCORF, they have a wide range of equipment which allow us to obtain information on the physical properties of the sediment cores. Physical properties data are useful as they can help determine the core stratigraphy, and influence how we decide to sample the cores later on.
To run the cores through the equipment, the first step is to use a pallet knife to clean up the surface of the cores. This ensures that the surfaces are as flat as possible, making them easy to scan, and removes any potential contamination since the cores were split on the ship.
We then run the cores through a machine which takes a high-resolution photograph of the core. These images are useful for describing how the cores look and any changes in sediment type!
Next, the core section goes through the Multi-sensor Core Logger. This provides information on magnetic susceptibility, p-wave velocity, colour reflectance and gamma density. All these parameters help build up a picture of the sediment properties.
The next machine used is called an ITRAX scanner. This tool generates data on the major elements within the sediments, for example Fe (iron) and Rb (rubidium). These data can help to infer information about the origin of the sediments, for example, if it has been washed off the land or contains lots of calcareous material of marine origin. The geochemical signatures may also allow us to determine periods of environmental change recorded in our cores.
Finally, the cores were scanned in an X-Ray scanner. Much the same as how an x-ray machine in a hospital shows bones beneath the surface of your skin, this scanner provides a high-resolution image of the material, such as shells, that are beneath the surface of the cores. This is useful as it allows us to see if there are shells embedded within the cores!
A huge thanks goes to the team at BOSCORF for letting us use their state-of-the-art facilities and sharing their expert knowledge. We are very excited to get the data back and see what we can find out from our sediments!
