At last!

Well, the cruise MGL1206 finally ended. We arrived in Honolulu this morning, a day earlier than originally planned. The weather got so much better once we left the survey area, and we were able to sail at 12 knots for most of the transit. Thanks to the hard work of the ship crew, science techs, and watch standers, our scientific mission was accomplished in full. I'd like to emphasize I'm always very much impressed by the professionalism of the Langseth crew and science techs. The fact that they are great may not be surprising, because, to survive in the middle of the oceans, you should be able to not only expect the unexpected but also solve it quickly with what's available on a ship. Still, seeing those talented people gathered in one place and spending a few weeks with them is a real privilege for someone like me.

I sometime wondered what the role of a chief scientist would be. I certainly had to make a scientifically important decision, e.g., whether we should turn back to fill a gap in data or keep shooting, but that happened only twice. Planned data acquisition was streamlined so nicely by the science techs, and I just had to keep myself out of their ways. Watch standers were all great and hard-working, and they rarely needed my instruction. One thing I did for sure is keep being worried. A cruise like this can give you more than enough to worry, such as instrument failure, bad weather, strong currents, sickness, injury, and encounters with marine mammals. Actually, all of those bad things happened during the cruise, but fortunately none of them was too grave to prevent us finishing our plan (phew).

To me, this is not the end of a 23-day cruise. In my mind, the whole thing started in July 2010, so I guess I've been under certain tension for nearly two years. Now with everything we wanted in our hands, we can finally decipher the mystery of Shatsky Rise. We'll be busy for at least another year!

I'd like to thank everyone for everything. I hope someday I'll come back to this wonderful ship and work with these special kind of people again, with a new exciting idea to explore.

One more day

As we approach Hawaii from this seemingly long transit, I find myself becoming more and more excited to walk on land again. There is no doubt that I have had a great time on the sea, during both the calm days and the rough ones, but all good things must eventually come to an end…unless you live in Hawaii. Apparently the fun never stops and people don’t age. Well, at least that’s what my watch partner Heidi says. I’ve been convinced to extend my planned stay of approximately 10 hours to another 4 days. Instead of getting off the boat and basically going straight to the airport and back to Texas, I’m going to stay for a week. That way I’ll be able to relax for a few days in Oahu and have a mini-vacation before I go back to the real world and defend my thesis in early May.

We’ve had so much down time on this transit to Hawaii that I’ve accomplished a lot of work. Besides working on my thesis defense presentation, I have read Wally Broecker’s How to Build a Habitable Planet and Alexandre Dumas’ The Count of Monte Cristo, and now I’m working on Robert Warren’s All the King’s Men. Every day at 3PM, Heidi and I compete against one another in paper football, and Tanya is the referee. Time usually flies by extremely fast most days because we are keeping ourselves pretty busy. I usually also download and read some new geology-related journal articles to keep focused on some science. Each day inevitably ends with some stargazing. The only light pollution comes from the ship but the nights are still extremely dark and clear. I’ve seen lots of satellites orbiting the planet and several shooting stars. I kind of wish I had a telescope, but the nights are still extremely breathtaking.

On a different note, a significant portion of papers that I’ve read related to marine geology or marine geophysics has invariably utilized a ship such as the R/V Langseth to obtain those pertinent data. At the end of these papers there is usually an acknowledgements section thanking everyone who took part in the cruise. I had an idea of the hard work that is necessary to make a research cruise successful, but it is another thing actually experiencing it firsthand. Each cruise is given an allotted amount of time to complete its objectives, so it is almost impossible to waste any time. These ships are on a tight schedule and as soon as one cruise is over, another one is usually ready to start with little time in between. Therefore, it is imperative to work as quickly as possible while recovering the highest quality data possible. I have observed nothing but professionalism on this cruise and although I won’t be involved in the post-cruise data processing and subsequent publications, I am appreciative of the crew’s hard work and demeanor. It has definitely been a rewarding experience and it was so much fun meeting my 30 day family. If I’m lucky enough, I hope to go on another research cruise at some point before I finish my schooling.

NUMBERs

MGL1206 is ending soon. Look at the transit map that we have been keeping plotting location points every 4 hours (see attached picture). That shows more than a real time position plot. It's all about good memories of everything during this cruise: nice people (Mike&Megan will say "peeps"), great job (five planned MCS lines plus bonus of extended Line_D2 and a test_line), teams (Team Awesome, Team American and Team Seasick), party (streamer party, gun party, XBT party, Language learning party, even "error" party, Bern likes party things), and happy to see some "old friends" again like Jun, Robert, Dave, Mike Tatro, Carlos, Jack, Hervin, etc., as well as to make new friends. When Ben, one of the crews, reminded me that I would miss the cruise whenever I am back on land. Yes, of course. Like 2010, Langseth has done a beautiful job once again this year, or I should use the word "always" instead of "once again". Because the people of Langseth know exactly what they are doing. Thanks for all the good things and who make those amazing happen.

Numbers, I nearly forget the theme of this blog. So please know some important numbers of this cuirse:

1,987,200,000 milliseconds at sea (professional geophysicists use this unit)
430,570,471,400 bytes for all SEGD data (IT guy reads things in bytes)
1,074,290,818,000 seismic samples we collected (processing knows that)

Big scaring numbers, that cannot feel happy, but they could sound much smaller if you change into bigger units.You know that trick. However, even if we have an indentical number and unit, they still would feel different, depending on what you are talking about. For example, it sounds OK to spend 10 days transit from Shatsky Rise to Honolulu. How about taking 10 days to fly from Honolulu to New York City? That must be problem with that flight. So TB data can be normal for MCS, whereas that much of songs would need a super-Ipod. I apply this philosophy to my life to make things feel better. When I realize my savings in bank less than 1K, I will immediately change the unit from bucks to cents (I still have thousands!). Sometimes even worse, say <$10. Even not enough for 1000 cents, that can't sound right. Think about this, exchange it into some African currency, and it might give you a million! Take advantage of how to use numbers. Rule of thumb is to be happy~~~!!

Travel time

Here we are only four days away from Honolulu, after some 2 weeks and a half at sea. This is my fourth cruise and it will be the longest one so far. And the first leg of the Shatsky Rise cruise lasted for 60 days! But, exactly how long will this second leg take? That is, with all the date and time changes, what will the real duration of the cruise be? We sailed off at around 8 am on March 24^th and will dock at approximately 8 am on April 15^th, which gives 22 days. We had one day change in which we went back in time and repeated April 8^th, so it's 23 days. Finally, when we get to Honolulu we will have made four hour changes of +1 hour, which means that we need to subtract 4 hours from the real time duration. Then my final approximate guess is 22 days and 20 hours. Is this correct?

Last day I posted was April Fools' Day, today is Cruise Picture Day. At 1 pm this afternoon, we all gathered in the muster deck, just behind the bridge, and arranged the picnic tables so that the people in the front could sit and the people in the back could prove that they had been in the cruise too. This may sound corny, but this is probably the best souvenir I will be taking home. Unfortunately, for the moment I can only tell you the story because the pictures are not uploaded yet, but I'm sure we will get to see at least one of them in one of the following posts.

But this is a science cruise, so I guess I'm supposed to have some science content in my posts. In the previous one I told you about my thesis main topic: travel-time tomography which is used to model wide-angle seismic (WAS) data. In this second leg of the Shatsky Rise cruise only MCS data have been acquired, so maybe some of you don't know exactly what WAS data is about. In the first leg of the cruise though, there were a couple of WAS data profile and if you check the older posts you will find all you need to know on the acquisition of this kind of seismic data. But once collected, what do we do with these data? That is precisely the purpose of tomo2d and tomo3d. From WAS data we obtain the time interval of seismic waves traveling from source to receiver: the observed travel times. From these, we want to recover a velocity model for the Earth subsurface. Briefly, what the two TTT codes do is simulate the source-to-receiver rays, calculate synthetic travel times for them, then compare these with the observed ones, and finally translate these differences in travel time, or travel-time residuals, to changes in the velocity model. This process is repeated until the resulting velocity model produces synthetic travel times that fit our data to a desired level of accuracy.

As you will know, Team Awesome is also Team Multilingual, and we have had time to learn some French, Chinese, Spanish and of course English. As this likely to be my last post, I'm going to leave you with a multiple choice question to improve your Spanish. The question is based on an anecdote that I'm glad didn't happen to me (you can ask me about it), and I think it will be useful if you ever get a cold while staying in Spain, although English takes you almost anywhere these days: What is the Spanish translation for “I have a cold”? (a) “Estoy constipado”, (b) “Tengo frío”, (c) “Estoy resfriado”, (d) Both (a) and (c) are correct, and (e) “Tengo un frío”. I realize that 5 possible answers is probably too many, so here is a hint, the literal translation of “I have a cold” is a wrong answer.

Oh, I almost forgot! In my first post I said I would tell you about the “First and Second Last Names Paradox”, from now on FSLNP. The FSLNP arises from the fact that in Spain newborns are given a last name from their father and another one from their mother. The tradition is that the first last name of your father be your first last name and the first last name of your mother, your second last name. But nowadays you can have that the other way around too. A funny consequence of the FSLNP is that when we travel to the US, our first last name is assumed to be our middle name and our second last name is picked as our last name. That is basically what happened here on the Langseth, where I've become Adrià M. Catalán.

In transit to Honolulu

             We finished shooting five days ago. On the last day of shooting, Ted and I went to the stern on a super foggy day and listened to the guns. Nobody told me we would be able to see the vibrations that occur on the water milliseconds before the shot! It is really cool to see but when we tried to videotape it, it was too dark. I don’t understand why we decided to go to the stern and take pictures on the last day of shooting! We should have gone earlier.

Now we are in transit to Honolulu. The shooting is done and the lab has become uneventful. We are doing 30 minute logs, BIST tests, XBTs, and adjusting the sonar window every time the sea floor changes considerably. There is a lot of time to be pensive. I’ve been curious about the Bridge. We had a tour of it when we started the trip, but it was short and fast. Ted and I got to go up to the Bridge and get a more in depth description of all the equipment they use and we were able to ask the chief mate a million questions. We also got to know what it feels like to sit in the VIP seats on the R/V Marcus Langseth.

The most confusing aspect of this trip so far is the date and time! It seems like the easiest detail to understand and remember, but not on this ship. We have gone through at least 4 time zones, we had Easter Sunday twice, an 8 day week, and of course the UTC time never changes. You can imagine what it’s like to schedule our time to use the phone to call our families! At least we always know what the UTC time is and what Julian Day it is, but nobody at home uses Julian Days. Yesterday we crossed the dateline. It was fun to watch the computers get confused.

So the captain said we might get to the islands earlier than expected. Everybody seems to be looking forward to it. Personally, if I would have packed a little better for this trip it wouldn’t matter to me if we got in early. I am starting to run out of everything!

Since this is my last blog, I just want to say I enjoyed the last few weeks with the company of my new ship family. You all have taught me A LOT and opened my eyes to even more different kinds of lifestyles. A special thanks to Jun Korenaga and William Sager for allowing me to be part of this scientific adventure!

Share photos!

To the whole Shatsky science party: Please use the ship "DONATE" media folder to upload any pictures and/or video you have taken on the cruise, particularly those of your fellow crew.

Multibeam

     My job on the ship is multibeam processing.  The ship's hull mounted echo sounder sends an unrelenting barrage of sonar beams as we travel through the sea, constantly mapping Neptune's hoary depths. The sonar beams are sent in a fan shape which lets us map, from our small boat, sections of the sea floor that can be from 15 to 25  kilometers in width. However, things such as rough seas, or perhaps occasional interference from other machines, causes bad pings to show up, which have to be edited out by hand. Actually, this is where most of the time is spent. Oh the capricious dance of ping editing. The life of a ping editor is a lonely one, filled with hardship and danger. But, as they say, someone's got to stand the heat and stay in the kitchen. For a brief moment, I was able to convince Yan Ming to help me with this task. Together, we were a two-headed hydra coursing our way through new realms of science and discovery, hoofing it with great gusto and leaving our venom deep in the hindquarters of bad pings, wherever they may be. But sadly it is true that nothing gold can stay. Yan Ming quickly left to find more interesting things to do. Once again, I was a wolf bereft of a pack. But I endeavored to persevere! And as the nocturne hour gave way to day I finished editing all the pings and raised my fist in triumph and shook it at the heathen Sun.
     All rambling aside,  multibeam processing is something that I am quite proud to do. After a day's worth of data has been cleaned up, I use it to  make a map.  Existing maps of the area estimate the sea floor topography based on satellite read gravity measurements and have a resolution of only around 2 kilometers or so. The new maps that use multibeam data have a gridding resolution of 50 meters. Canyons and underwater mountains that once lay hidden now reveal themselves. Many of them have never been seen before. I get the first look at the map and can see the big picture of new discoveries. That's a pretty neat thing.