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Its day 19 of this cruise on the R/V Langseth, and we have been deploying the seismic gear for the last 18. After the 12-hour process of deploying the 12-kilometer streamer, 4 strings of airguns, and 2 sensors, we were ready to being “shooting” and collecting data. Once all the equipment is deployed, we must maintain a speed of roughly 3-5 knots to maintain good tension and depth on all the equipment being towing.

As the airguns shoot (approximately every 50 meters or 20 seconds) it sends a sound signal that penetrated miles into the seabed before reflecting and being read by the hydrophones along the streamer. The hydrophones are extremely sensitive underwater microphones that convert the sound signal sent by the airguns into seismic profiles. These seismic profiles show the layers of the seafloor by recording how fast sound moves through each layer.

This week we needed to check the streamer and record videos of it firing. I was lucky enough to be chosen to go on the small boat with a few others. We used a GoPro taped to the end of a metal arm that was then lowered into the water next to the streamer. All these photos came from the video.

The yellow buoys are the head floats on each of the 4 gun strings. Each gun string has 9 airguns on it that are towed at a depth of 10 meters. The airguns are the sound source and critical to the data collection.

Approximately every 20 seconds (or 50 meteres) the 36 airguns fire. When they fire, they create a huge sound wave that makes deep-sea floor mapping possible.

Behind the 4 airgun strings is the streamer with the hydrophones on it. The streamer extends for 7.5 miles (or 12 kilometers) behind the ship, and has 47 Digibirds on it. The Digibirds (pictured below on the streamer) use their depth sensor and wings to keep the streamer at a constant depth of 12 meters.

I’m extremely happy that I got to go on the small boat and check out the equipment that we’ve spent so many days prepping, deploying, and watching on screens. Maybe next time I’ll even get to go swimming…

Day 15 (7-27)
The water was like glass this morning — it was such a beautiful (and blinding) sight! 
The night shift is great for many reasons, and watching the sunrise is definitely one of them. 

Day 16 (7-28)
Inventory day today–lots of counting, stacking, and learning about the uses of LAUMs, TAPUs, and HAUs. 
(Line Acquisition Unit Modules, Tail Acquisition and Power Unit, Head Auxiliary Unit). Thankfully I stored them all in order of their serial number (it made finding the specific one I was asked for later in the day MUCH easier to find–hooray for organization!)

Day 17 (7-29)
The first truly rainy day on the boat today! 
Lightening struck just off the starboard side and it actually took out a few of our systems–the Maggie (the Magnetometer), the Visala (a weather station), and a hydrophone. 
I learned that the PSOs actually cant remain in the tower during these storms, its too windy and the boat heaves more than usual, so they stand in the bridge and keep watch for species of interest instead. 

Day 18 (7-30)
Riley and I learned how to play cribbage today! The night shift continues to be lovely–the ship is calm and quiet when I wake, and every now and again I go outside to watch the sunrise as it lights up the horizon. 
Aside from continuing to write the New-Joiner documentation (like an on-boarding document for new interns like myself) Cody and I went up to the PSO tower today to fix the Visala (the weather station). 
It is a small white device, about the size of a massive grapefruit, mounted on a pole with an antenna on the observation tower.
I learned how to plug into the device and navigate it’s interface, making sure that the correct information (in the correct format) was being communicated to the main lab: wind & wind direction, heading, air temperature, etc. 
After re-mounting and making sure the antenna was facing the proper direction the rest of the day was spent watching the navigation screens, and doing some light reading. 
I often like to sit on the bridge to read in the sun when its not too hot out, or under the shade of the crane on the OBS deck. Its a bit loud at times, but nothing some ear plugs cant fix! Plus, you cant beat this view. 

Day 19 (7-31)
I would recommend all new people remember to bring cash for the slop shop! 

Day 20 (8-1)
I feel like I have really settled into a routine here now! 
The days start so calmly when your shift starts at 1145pm. The boat is (relatively) quiet and its nice to take a walk/stretch your legs by going up to the bow and looking at the stars. 🙂 
Most days are filled with watching the mission control monitors and handling line changes (the EOL/SOL procedures, Navigation Log duties, etc.)
It is really quite nice to get away from the hustle and bustle of everyday life while on the boat, and to focus on the immediate tasks at hand, and learning about the data being taken from the science crew during our chats is an extra plus!
Paper discussions are being held every few days now, which are fun to attend when I get the chance to read the paper that is being focused on. 

Day 21 (8-2)
Now that the schedule has seemed the settle and work remains similar most days, I will mostly just be updating with photos and comments on new and excting happenings on board. 
Happy sailing! 
 

Day 8 (7-20)
We had to do some adjustment on several birds last night and when I got on shift today it was a fun experience to be on the radio and help deploy the birds as they were attached to the streamer, and then released into the water. It involved a lot of radio-ing back and forth with the crew on deck attaching the devices. We noted serial number of the bird and its position on the streamer, and since the birds communicate wirelessly we could then use the Sys3w0I software in the main lab (the software that controls the birds and communicates with them) to conduct a final calibration check, making sure the wings had a full range of motion, the compass worked properly, and that the depth/pressure sensors were reading proper values. 
It went something like:
“Digibird 01, serial number 12345, confirmed; testing now”
and
“Digibird looks good, wing reset started, if you see movement, you are ready to deploy!” 
fun times on the phantom shift!

Day 9 (7-21)
After the excitment of yesterday today was pretty calm! I came up with a system to ensure that I would check all of the systems I was taught to monitor a couple days ago. I numbered every process, and count–out loud–each process as I look at the numbers and ensure they are in the correct ranges. 
Helpful for making sure I dont miss anything and dont accidentally glaze over any numbers. 
One of my team members on the night shift has brought New Yorker magazines with him to the ship, and the team down here has had a fun time collectively tackling the crossword!

Day 10 (7-22)
First thing in the morning today I learned how to calibrate the Gravimeter.
It is exactly what it sounds like — an instrument for measuring gravity. Gravity changes slightly depending on your location on Earth, and this extremely precise machine, made by Bell Aerospace, measures these small fluctuations. 
The machine has a very cool, retro look to it. I look forward to probing it with the multimeter next Monday for the weekly test! 
Today was also the day of our first line change! 
As a Navigator intern I felt that I got my first “real” taste of Navigator duties as I went through the End of Line (EOL) and Start of Line (SOL) procedures without assistance (though certainly with supervision, as it was my first time going through the steps), which include noting all process “vitals” (the processes list I named a couple days ago) and writing several key events in the Navigation Logs, starting and stopping the air guns, informing the Observers/Acquisitioners of the upcoming line change (these are the crew members that sit next to me at Mission Control and monitor the data acquisition and status of the hardware) and coordinating with them about any possible air-gun or network/communication configuration changes. Finally we radio the bridge to ask when the ship will begin deviating from the current line (though they normally beat us to it!). 

After work I was able to do some reading outside, and started my second book! While enjoying the outdoors a fellow crewmember and I tried to spot a baby hammerhead shark that was seen off the bow of the ship. 🙂 
(We didnt spot it, but it was cool regardless)

Day 11 (7-23)
Eating breakfast (which as at 7:20AM, approximately my lunch time since I have been awake ~8 hours at that point) never gets old. Today our chef extraordinare, Ricky, made cinnamon rolls that were TO DIE FOR. Have I mentioned yet how good the food on this ship is?
There is also a ship-wide t-shirt contest, which I started designing for! The design is mostly an inside joke between myself and several of the crew, we will see where it goes! 

Day 12 (7-24)
All is calm on the water today, line is going well, waves haven’t gotten bigger than 1 meter, hooray for calm days and lots of reading!

Day 13 (7-25)
Relabelled a few large wires that run from the deck to the server room today, and learned about wiring the guns that was fun! Got to do more EOL/SOL procedures. The whole crew was excited today for the group of five people that got to take the small boat out to take video/check the status of the airguns in the water! 
Once they get back we will all get to see the footage of the airguns under the waves, which will help the crew and technicians determine what we can do to improve their positions in the water and/or confirm that they are working properly. 

Day 14 (7-26)
Update on the T-shirt drawing:
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I am also working on a “New Joiner” document that will be used to help future interns (like myself) prepare for life on the Langseth and get a general understanding of the types of scientific operations conducted on board. 🙂
Not much to report, easy sailing today!

This is my third and last cruise as a MATE intern aboard the R/V Langseth. This last cruise will be very different that my previous two, which collected sediment cores and ocean bottom seismometers respectively.  This cruise will use the Langseth’s highly specialized seismic equipment to collect multichannel seismic data. It is currently the only UNOLS vessel able to collect this type of data. Essentially, this means we will be towing seismic equipment that uses sound waves to create highly detailed maps of the geological features under the seafloor. 

I have spent the last week working with scientists and contractors from all over the world to prepare the seismic equipment for deployment. I have been gaining an intense crash course in geology, seismology (the study of earthquakes), and basic mechanics.

Here’s the basics[refer to pic below]: The seismic equipment is made up of airguns, streamers, and Digibirds. The 36 airguns create a loud sound that then travels through different layers of the seabed before bouncing back to be heard by the 12 kilometers of streamer. The streamer has thousands of hydrophones (precise underwater microphones) along it that receive the sound signal and create a high-precision map. There are also 47 Digibirds (orange winged “birds”) that use their wings to control the depth of the streamer.

We spent the first 2 days calibrating the Digibirds (pictured in rack below) which help us keep the streamer at a precise depth (12 meters). The Digibirds have a sensor on them that determines depth based on pressure, it then moves it wings up or down to move shallower or deeper based on programmed depth. It was a two-day operation to deploy the entire 12 kilometers (7.5mi) of streamer with hydrophones, 47 Digibirds, and 36 airguns across 4 strings. Now that everything is deployed, we will monitor the equipment for changes as we tow the seimic equipment across the survey lines.

This is a Digibird in the Bird Lab, where we calibrate its depth and test it before deployment. We prepped 55 Digibirds before deploying the 12 kilometers of streamer. 

Here is the back of the boat towing the seismic equipment. The four yellow lines go to the four airgun strings (each has 9 airguns on it; the 4 airgun strings are the sound source) and the white line is the 12km streamer (where hydrophones recieve the sound after it bouonces off the seafloor).