January 21st

Log Entry by Tamra Dickson

Today is the third day we've been on the boat but you can't really tell by days and night. Everyone feels like it's just one big day with lots of little naps in the middle. Day and night, morning and afternoon don't matter anymore, just on and off watch, onstation and transit. We had another big group stations today, the third of six. We have also done Hillary's EM300 mapping of the seafloor section she wanted and we are on our way to do Jaqui's box cores and CTD measurements. For those of you who don't know, the box cores collect sediment from the sea floor and the CTD collects water at desired water column depths as well as measuring chlorophyll, oxygen, temperature, density, pressure, light transmission and a few other things. It's a really nice machine to have. Today I ran the silica samples for my three stations as well as the one I volunteered to do for a classmate who ran out of time on the first leg. I also did some of the Ecuadorian scientists' si! lica samples and they will do some of my and wes's phosphate samples tonight. Whatever they don't do, I will do tomorrow along with Joni's and any new samples for phosphate that I have. Joni Werdeman is the other one studying nutrients on this cruise, she is doing the analysis for both of us for nitrate and ammonium and I am doing both our phosphate and silica. She did our nitrate today and will do the ammonium tomorrow. Each process takes 3 to 5 hours so it is best that we each do one a day. The hardest part though was finding all the chemicals for the first time, mixing the reagents and prepping the samples. Once that was done, the samples were easy to run, even though they took time. The phosphate and silica samples have chemicals added to them to make them a certain shade of blue based on the concentration. The samples are then put in a spectophotometer that reads how much % of light is absorbed from what is shined on the sample. That is how we figure out the phosphate and s! ilica processes. Our fourth station is at 2:30 this morning, but hopefully I will get some sleep between when I'm off watch at 8 pm and then.