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Life at Sea

The ENAM Seismic Experiment - Sat, 09/27/2014 - 22:34
September 27, 2014

Our small ship is in a state of endless motion with pitch, roll, yaw, and heave. We continuously experience a feeling of fluctuating gravity at sea, as one minute we are several pounds heavier and the next we are several pounds less. We’re tossed about endlessly like riders at the fair. It’s a feeling that can turn the stomach of the saltiest of sailors, but more often disturbs the newbies the most. At sea there is also no such thing as silence. Out here the engines are always running, hydraulic pumps are always droning, and ships operations occur around the clock. From my bunk I can feel us lurch forward and lean into a turn to starboard, or port, and then they reverse the pitch of the propeller as if applying an emergency brake to slow the ships forward motion. This reverse pitch causes a shudder in the hull that shakes us like a cheap hotel vibrating bed and it chatters every moveable thing. From my bunk I can also hear the acoustic pings emanating from the hull-mounted transducers. Speaking to me in code, they tell me if OBS operations are going well.  Based on the ping styles I can also discern the acoustic techniques used by WHOI and Scripps, so that I know which instrument type is being talked to. All of this information creates a movie in my mind that plays out until I fall asleep. Life on a ship is a constant immersion in all that is going on and for 30-days there will be no escape.

-Ernie Aaron

And then there was data…..

The ENAM Seismic Experiment - Fri, 09/26/2014 - 21:10

It’s been a week since we deployed all of our gear and started steaming along our lines, so now we have amassed a lot of data!  Although we can only steam at very low speeds while towing the equipment (~4.5 nautical miles an hour or  ~5 mph), each time we fire the air gun array, the 636 channels on the seismic streamer listen for returning sound waves for 18 seconds and record a total ~25 Mb of data. Repeat that every 30 seconds for 7 days, and it begins to add up!  We now have 400 Gb of seismic data alone, not including all of the other types of data we collect while underway (bathymetry, magnetics, gravity).  We are a data-collecting machine.  

Matt, Jenna and Derek sit  back and watch the data roll in from the Main Lab
Not only are we collecting data, we are also doing some preliminary data analysis to get a first look at the geology hidden below the ocean, which is always exciting.

Kara and Matt are entranced by velocity analysis
Although we are only a week in, our data collection has already taken us through water depths as shallow as 20 m and as deep as 6000 m.  At the edge of the continental shelf, water depths change rapidly from ~500 to ~3000 m over just 20 km – a slope of 10%.  For perspective, that’s very similar in elevation change and slope to the course for the Pikes Peak marathon.

Perspective view of seafloor depth from MGDS across the continental slope overlain by a higher resolution swath of bathymetric data that we acquired along our transect, which is also shown projected onto the seafloor.
We have also traveled over widely variable geology – from 35-km-thick continental crust to ~7-km-thick oceanic crust, and from sediment thicknesses of 5 m to over 7 km.   Our data are also revealing cool structures in the sediments and crust – faults, sediment waves, and more.  Below is a picture of a salt diapir that we imaged at the edge of the continental margin.  The salt was probably first deposited at least 150 millions years ago in a flat layer, but as more sediments were deposited on top of it, it got squeezed up and out into dramatic diapirs.

Preliminary image of a salt diapir in seismic reflection data near the base of the continental slope. The y-axis shows the time it takes for a sound wave to travel down in the earth and back again. This images shows about ~5 km down into the earth below the seafloor. Donna Shillington aboard the R/V Langseth

First day of land deployment - showing kids how cool seismology is - by Kara Jones

The ENAM Seismic Experiment - Fri, 09/26/2014 - 16:32

(Originally posted on September 12)

Today was the first day of the onshore deployment of the RT130s through southern Virginia and North Carolina. My partner, Yanjun Hao, and I, were just one of five teams working to deploy instruments along the two survey lines. We deployed the first two instruments at West Harnett Middle School and South Hartnett Elementary School, both outside of Lillington, NC. In both case, the fifth and sixth graders were very interested in learning about what we were doing and eager to participate. I explained to them the basic concept of P and S-waves and then asked the children to jump so that we could test that each of the channels on the sensors was working correctly. They very much enjoyed getting to see on the clié exactly what the signal they generated looked like. At both schools, I was surprised how much the children, and the teachers, knew about earthquake seismology and the intelligent questions they asked. A teacher asked whether they would detect the explosives detonated at nearby Fort Bragg, and a sixth grader named Gauge blew me away when he asked if the sensors would be able to record the sound waves generated by the planes or nearby explosions! In total, we probably spoke to 100 kids about the project today. It was a very encouraging to see how excited and interested they all were in the science. When we first arrived and explained that we would be installing a seismometer, a 5th grade teacher looked at us with wide eyed and asked "Are you seismologists?!" I nodded yes and she was so excited she started jumping up and down. Despite some rain and GPS trouble later in the day, the excitement that the elementary and middle schoolers showed about seismology was enough to make it a great start to the deployment.

At South Hartnett Elementary School in Anderson Creek, NC. I am showing one fifth grade class what the seismic signal they just generated looks like on the clié.

The land instruments

The ENAM Seismic Experiment - Fri, 09/26/2014 - 16:26
The insulation was tough but gratifying. The weather in North Carolina is unpredictable. At times it was hot and humid. I was drenched in sweat burying the sensors. Other times we were caught in torrential downpours working under a tarp; terrified by the sound of thunder. The sites were located on mostly private property, hosted by people who were eager to help with the experiment. The interaction with the local people enriched the experience. Many of them showed true southern hospitality. 
Station deployed!
From an academic prospective I learned about survey design, instrument deployment and the logistics. This provided a distinctly unique experience that is unavailable in the classroom environment. Beatrice and Dan were tremendously helpful and supportive. I learned a great deal about active seismic from my conversations with them. They’re passionate about nurturing future geophysicist. The GeoPRISMS is an altruistic endeavor for them. I am thankful to them for investing so much of their time and expertise into the project. 

The GeoPRISMS experiment has been an overwhelmingly positive experience. I am grateful to have been given the opportunity to help with the deployment and look forward to my involvement in the recovery of the instruments! A future workshop will be held for processing the data and the inversions. This pre to post educational approach is invaluable to me as a future geophysicist.

Posted by Christopher Novitsky 

The Land Deployment Team!

The ENAM Seismic Experiment - Fri, 09/26/2014 - 15:30
From L-R: Yanjun Hao, David Boyd, Dam Lan, Ana Corbalan, Christopher Novitsky, Pnina Miller, Jason Leiker, Kara Jones, Beatrice Magnani (front), James Farrel (back), Dan Lizarralde.It took us a while, but here we are, the team that deployed the land seismometers on Sept 12-15. The instruments are now continuously recording the Langseth shots and will continue recording for few more weeks. The East Carolina University in Greenville, NC graciously allowed us to use one of the research facilities on their West Campus (a place with a fascinating story - blog on that coming soon!) as the headquarter for operations. We will be back to the field at the end of October to pick up the instruments, download/save the data and demob.

Posted by Beatrice Magnani

The Night Watch in Action!

The ENAM Seismic Experiment - Fri, 09/26/2014 - 12:29
We've captured the process of recovering and deconstructing a Scripps OBS thanks to Harm's nifty GoPro camera attached to the crane. This OBS was a little tricky to hook, but otherwise it was a smooth recovery!

Time series of the recovery after the OBS has been attached to the crane. Photo Credit: Ernie Aaron.

See ya'll later,
Jenny Harding
R/V Endeavor


Geopoetry - Fri, 09/26/2014 - 10:00


Aerial view of a brown tide caused by Aureococcus anophagefferens. Long Island. Photo by Chris Gobler.

Aerial view of a brown tide caused by Aureococcus anophagefferens. Photo by Chris Gobler.


On skin, it’s barely a freckle I’d make,

But baby, en masse, we turn seas opaque!

Come darkness, come famine, come poison or flood,

My kind can flourish in any old crud.

I may be a tiny and brainless brown cell,

But my tactics are brilliant; I’m doing quite well.

So, “higher” life-forms, with deep-furrowed brow,

I’ve made my move … what will you do now?



Further reading (on what humans are doing now …):

Like Weeds of the Sea, ‘Brown Tide’ Algae Exploit Nutrient-Rich Coastlines, Earth Institute

De novo assembly of Aureococcus anophagefferens transcriptomes reveals diverse responses to the low nutrient and low light conditions present during blooms, Frischkorn et al., Frontiers in Microbiology


This is one in a series of poems written by Katherine Allen, a researcher in geochemistry and paleoclimate at the Lamont-Doherty Earth Observatory and the Institute of Marine and Coastal Sciences at Rutgers University.

What are we up to

The ENAM Seismic Experiment - Thu, 09/25/2014 - 16:09
September 25, 2014

        For those of you following at home, it might be a bit confusing on which ship is doing what and where. I've made a little cartoon timeline that will hopefully illuminate our progress so far.
       There are two ships currently in the Atlantic: the OBS deploying R/V Endeavor and the seismic shooting R/V Langseth. The R/V Endeavor has been putting OBS down and picking them back up again on lines 2, 3, and 4 while the R/V Langseth has shot seismic along line 2 and 3, and is going to head over to shoot on line 4 soon.

See you later,

Kate Volk aboard the R/V Endeavor

Group photo time

The ENAM Seismic Experiment - Wed, 09/24/2014 - 13:30

September 24, 2014

Well we have finished deploying OBS on line four and are now transiting back to the beginning of line 3 to start picking OBS back up again. At this point, we've all fallen into our jobs and are working like a well oiled machine. Each shift was able to deploy around 9 or 10 OBS in 12 hours time, moving smoothly from one site to the next. To celebrate our progress so far, I've got some group photos to share.

The science party from left to right: Gary, Dylan, Afshin, Harm, Brandon, Pamela, Jenny, and Kate (Photo credit: Dave DuBois, edited by Gary Linkevich)
The WHOI and SIO OBS technicians from left to right: Ernie, Peter, Mark, and Dave (Photo credit: Gary Linkevich)

The whole science group (Photo credit: Ethan, edited by Gary Linkevich)

The science group in the WHOI van with the WHOI OBS (photo credit: Dave DuBois)See you later,

Kate Volk aboard the R/V Endeavor

Dinner Time

The ENAM Seismic Experiment - Tue, 09/23/2014 - 23:53

September 23, 2014

Good eats! We couldn’t do this cruise without our great Chief steward Mike. Mike keeps the morale up on the ship by preparing three fabulous meals a day, plus providing ample snacks and baked goods. I’ve especially enjoyed the coffee cake, macaroni and cheese and tomato soup, oh and pretty much every dessert he’s made. Mike is especially awesome at accommodating everyone on the ship and providing tons of variety for us. He includes meat dishes as well as vegetarian, whole wheat, and vegan options, all of them yummy!

The galley, Mike is preparing for dinner (Photo credit: Kate Volk)

Mike making dinner (Photo credit: Kate Volk)
Mike in the Galley (Photo credit: Kate Volk)

Dessert (Photo credit: Kate Volk)Kate, Gary, Kurt, and Dylan enjoying a meal (Photo credit: Kate Volk)

See you later, 

Kate Volk aboard the R/V Endeavor

UPDATE: September 23rd

The ENAM Seismic Experiment - Tue, 09/23/2014 - 16:43

September 23rd, 2014

The last few days have been a bit rough, with intermittent rain, winds at 15 – 30 kts, and 6 – 10 foot seas, but that didn’t delay our progress at all. When I woke up for watch late yesterday morning, the sun was shining, the seas were calm, we successfully completed recovery of the OBSs that we had deployed on Line 2, and we were in transit to the beginning of Line 4 to begin our redeployment. Now, over the past 26 hours, we have deployed OBSs along the entirety of Line 4 (22 instruments) and begun our transit to the south end of Line 3 to begin recovery of those instruments.

Until next time,
Dylan Meyer aboard the R/V Endeavor

Afshin's Birthday

The ENAM Seismic Experiment - Mon, 09/22/2014 - 18:18

September 22, 2014

Happy birthday Afshin! A member of the science team, Afshin from Oklahoma State University, celebrated a birthday on the ship. Our wonderful cook Mike baked a cake especially for him. Yum! 

Afshin (Photo credit: Kate Volk)
Mike's cake for Afshin (Photo credit: Kate Volk)

Afshin and Mike (Photo credit: Kate Volk)
Afshin with the birthday hat (photo credit: Dave DuBois)

sargassum seaweed

The ENAM Seismic Experiment - Sat, 09/20/2014 - 12:11
September 20, 2014

It’s been a long time since I’ve seen sargassum seaweed.  The brilliant blue Atlantic Ocean has such a different feel, smell, and color than that of the Pacific.  Sailing over the dark blue long-period waves and working among humpbacks, kelp patties, and Japanese tsunami debris is my typical science cruise.  It’s good to be back east and to be reminded of the profound, yet subtle differences of these two great oceans. -Ernie Aaron

Sargassum seaweed (Photo credit: Ernie Aaron)

OBS Recovery

The ENAM Seismic Experiment - Fri, 09/19/2014 - 22:41

September 19, 2014

At about 01:42 the night shift had successfully started a burn on a WHOI OBS located at the start of line 2. A burn means that the science crew was able to communicate with the device and send a signal telling it to burn through the wire holding the buoyant OBS to a metal weight attach to its bottom. The water depth in this area is around 5200 m, and it took about an hour and half for the OBS to rise to the surface once detached from the weight. The team located the OBS using a radio signal and visual contact (light and flag). With the OBS spotted, the Chief mate Shanna was able to maneuver the boat alongside the OBS, so that the science crew could snag it out of the water and bring it aboard. Since then we have recovered six OBS from both the WHOI and Scripps science crew. The seas have picked up a bit, but we are continuing to move westward along line 2 collecting the devices. From here we will prepare the OBS for redeployment along line 4.

See you later,

Kate Volk aboard the R/V Endeavor

The last OBS of line 2

The ENAM Seismic Experiment - Fri, 09/19/2014 - 22:40
September 19, 2014

On September 18, we finished deploying the last OBS of line 2. To honor the last deployment, we did some decorating of the side float of the Scripps OBS.
Mark putting the data logger into the Scripps OBS (Photo credit: Ernie Aaron)

Dylan and Kate attaching the strobe light and flag to the Scripps OBS (Photo credit: Ernie Aaron)

See you later,

Kate Volk aboard the R/V Endeavor

The ships meet

The ENAM Seismic Experiment - Thu, 09/18/2014 - 22:49
September 18, 2014

The R/V Endeavor crossed paths with the R/V Langseth this afternoon around 16:45. The Langseth was shooting line 2 while the R/V Endeavor was heading back to the start of line 2 to begin recovery. Here's a picture of the Langseth aboard the Endeavor.

The R/V Langseth taken aboard the R/V Endeavor (Photo Credit: Gary Linkevich)
See you Later,

Kate Volk Aboard the R/V Endeavor

The Night Crew

The ENAM Seismic Experiment - Thu, 09/18/2014 - 22:06

September 18, 2014

No breaks from science! The Endeavor runs 24/7. When we are doing a line, we launch an OBS about every hour and a half from the ship. Here are some pictures on the night crew hard at work.
Pamela, Afshin, and Ernie assembling the Scripps OBS (Photo credit: Gary Linevich)Pamela, Afshin, Ernie, and Jenny assembling the Scripps OBS (Photo credit: Gary Linevich)Pamela and Jenny admiring their work (Photo credit: Gary Linkevich)Ernie and Afshin hooking up the OBS (photo credit: Gary Linkevich)Charlie operating the crane (Photo credit: Gary Linkevich)
Launching the OBS (Photo credit: Gary Linkevich)

See you Later, 

Kate Volk Aboard the R/V Endeavor

Ships crossing in broad daylight...

The ENAM Seismic Experiment - Thu, 09/18/2014 - 21:41
We passed the R/V Endeavor today as she steamed towards the southern end of this profile, where she will begin recovering OBS after the Langseth has passed over them, and the OBS have had a chance to record sound waves that turned deep below Earth's surface.  The Endeavor kept her distance to avoid disturbing all of the seismic gear that we are towing behind the Langseth!

Donna Shillington aboard the R/V Langseth
The R/V Endeavor on the horizon...

Seismic gear is deployed, and we are collecting data!

The ENAM Seismic Experiment - Thu, 09/18/2014 - 20:43

Yesterday, we deployed the seismic streamer and source of the R/V Langseth in record time - its no small feat to put 8 km (~5 miles) of streamer plus other equipment in the water behind a ship.  The streamer is filled with pressure sensors that will record sound waves that have traveled into the earth and bounced off geological features, like faults, sedimentary layers, and ancient lava flows.  It is unwound from a gigantic spool on the back of the vessel.  As it leaves the ship, we festoon it with a variety of important devices, like “birds” that control the depth of the streamer, “streamer recovery devices” that are air bags that deploy and float the streamer to the surface if it gets too deep, and acoustic navigation units that are used to help determine the position of the streamer beneath the ocean surface.  A tail buoy is located at the end of the streamer to help with positioning and alert others of the presence of the streamer, and a float is at the front to further control the depth of the streamer. We also check that everything is working while we’re putting it into the water. We deployed all 8 km in just 7 hours, and were rewarded with a rainbow and spectacular sunset as the last bits of equipment went off the stern.   We also deployed the seismic source, which consists of air guns suspended below four snake-like black floats.  Now that all the kit is in the water, we are happily collecting data. Its a very good moment when the seismic data begins to come in...

Donna Shillington aboard the R/V Langseth
The top of the streamer reels. We are unspooling seismic streamer from the reel on the right. (Photo: Jenna Hill)
Looking towards the stern across the streamer reel (Photo: Derek Sawyer)Matt, Sasha and Carlos attach a bird to the streamerThe streamer entering the water behind the ship with a bird
Kara fetches a bird to place on the streamerMatt and Robert monitor the deployment operation from the main lab.A rainbow hovers over Jenna and Ben with the final bit of streamer (Photo: Derek Sawyer)

Transit update and food for thought

The ENAM Seismic Experiment - Thu, 09/18/2014 - 16:26

September 18th, 2014

I was awoken early this morning, after only a few hours of sleep, by some unknown portion of my subconscious and was struck by a thought concerning the unique nature of performing science at sea. The ocean, as a scientific laboratory, forms a constant connection with those who venture into it that is experienced by few, if any, terrestrial experimentalists. During my 12-hour watch, my mind is clearly engaged by the science that we are performing. When is the next instrument being deployed? What needs to be done to be ready for it? Will we survey this instrument once it rests on the seafloor? These are just a few examples of the many questions that cross not only my mind, but the minds of my peers as well. More interestingly, however, I also find that I am acutely aware of changes to my environment, which readily defy alterations in our scientific progress, even as I lay semi-conscious in my bunk. The temporal spacing between the response of the 12hz Echosounder pinging against the hull informs me of any relative change in depth from the last time I was awake. The direction and intensity of the ship’s sway can tell me about our heading and/or a change in weather conditions. A variation in the output frequency of the engine’s constant drone provides me with our current speed and suggests what kind of scientific activity the other watch might be performing one deck above my head. It the result of these types of observations that those aboard these floating beasts that operate 24-hours a day are constantly engaged in their environment, whether or not they desire to be. Anyways, perhaps this helps orient those who have never been to sea for an extended period or recalls reflection for those who have ventured out into the wild blue yonder previously, either way I felt it was an interesting thought worth sharing.

Currently, the R/V Endeavor is a little over halfway through its transit back to the end of Line 2. Along the way, we surveyed OBS Sites 210 and 211 to accurately locate each device on the seafloor which will assist with our recovery. Once we reach the eastern end of Line 2, before starting our recovery operations, we will perform a rosette test. However, the event that all the scientific party is looking forward to is passing by the R/V Langseth sometime early evening and waving ‘hello’ to our scientific comrades.

Till next time,
Dylan Meyer aboard the R/V Endeavor

One of the crew, Chris, noticed this awesome moth that landed on deck yesterday. A clear sign that we were close to shore (Photo Credit: Dylan Meyer)

After passing through a heavy squall, we were rewarded with a full rainbow! (Photo Credit: Dylan Meyer)



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