A trip across the Santa Barbara Basin--June 2008

Here's the ship we sailed on.

Our goal was to retrieve sediment from several locations in the Santa Barbara Basin. Why? To use the sediment as a record for oceanic variability. Sediment cores from this area are great because of the high sedimentation rate, which is about a cm per year after compaction. Cores were retrieved several years ago, but we would like to see how our sediment proxy (the shells of foraminifera, which provide a view of ocean conditions) has changed in more recent years. The sediment here is not compacted at the surface, which makes it difficult to retrieve this "coretop" material without some loss. We used a multicorer (gets a good amount of material with a relatively clean sediment/water interface), a boxcorer (retrieves a larger amount of material with a clean sediment/water interface), and a CTD with rosette of niskin bottles to retrieve water.

Science Crew Part 1: Jonathan LaRiviere, Lydia Roach, Heather Ford, Patrick A. Rafter

From this photo, you'd think they were unfriendly... Science Crew Part 2: Vicente and David Field

RV Sproul Resident Technician watching the line... early morning Santa Barbara Basin

Recovering the CTD

I have to filter my water samples to remove all the microbes. They can alter the nutrients that will be eventually measured.

The multicorer settles on the sediment surface and presses its 8 coring tubes into the sediment.

Deploying the multicorer

Recovering the multicorer

You take each multicore off, put it in a walk-in refrigerator / lab and eventually push it out of the multicore tube. Here we are sampling every 2 cm.

You can also stick a "liner" in the multicore tube and retrieve your sediment that way. Here's what a liner retrieved from a multicore looks like. We've captured an orange mollusk in this one. If you asked yourself, "why don't they just bring a bunch of cores, so they don't have to transfer anything?" You'd be thinking the same thing I was when I learned what we were doing. Next time!

Fantail fantasies

One of the best boxcores of all time. There's a great story behind this one... you'll have to ask Vicente. The "shovels" are cocked in an upward position with thin pieces of twine, exposing the main "box". When the boxcore penetrates the sediment, the strings break and the shovels close the bottom of the core off, so we can bring it back on board (the top of the core also closes at this point).

We bring the box core back on board and then shove this "liner" down into the sediment--trying not to disturb the sediment/water interface.

You freeze the bottom of the boxcore/liner and remove the liner. It's not as easy as it looks. We're pulling it out, cleaning it, and putting a cap on the bottom at the same time.

Pretty