Our First Sunset in the Northern Hemisphere!

Solid 8/10. The clouds lingering on the horizon obstructed the full potential of this sunset. ---Angel 

R/V Revelle Equator Crossing

Hear me, hear me

On the 18th of September 2013 we crossed the Equator at 142 degrees and 30 minutes east longitude, reckoning from Greenwich. After battling large mud waves and numerous foraminifera with multi, gravity and piston corers we finally achieved our goals here by deploying the mighty Kasten corer and shooting the mud with air guns. In recognition of this major victory and the crossing of the equator we salute the Southern Hemisphere as we move to the new battlefields in the north with the traditional mud decoration.

I hereby, King Neptune, also known to many as chief scientist, will now baptized all you Polywogs with equatorial Pacific surface water. From now on you will be known as Eq Pac Shellbacks and will contnue this old tradition when your turn comes to become chief scientists. ---King Neptune

Getting to Know the Cap'n

      When you're at sea on a research cruise, scientists only make up part of the population on a ship.  We're actually just visitors here - lots of space and time are shared with the crew, who call the ship their home.  So it's great to take some time to get to know the people you'll be living alongside for a few weeks.  The other morning I had the chance to talk with the captain, Wes Hill, the third mate, Matt Serio, and AB Pete Steiner up on the bridge a little bit about life at sea.  Below is a summary of what was said "on the record."  For the off the record transcript, you'll have to find the captain in Manila after the cruise ends!

 
      I got to know our Captain a bit first.  Wes has been a captain since 2000, but has been with Scripps for nearly 24 years, and he's known many of the crew for almost as long.  Before becoming captain, Wes was a mate.  He sails with all of the Scripps fleet but has been at the helm of the R/V Revelle for the past three years.  When I asked him if he had a favorite ship, the captain replied, "No comment."  A very PC answer!

      I asked Wes about his favorite and least favorite parts of the job.  He said interacting with the scientists was great (and I'm sure not just because he was talking to one at the time), and of course the travel, listing Taiwan as his favorite port, and Easter Island as one of his favorite places he's been.  The biggest drawback is all the time away from home.  To give you an idea of the kind of time the crew spends at sea, the Revelle has been cruising around the western Pacific since mid-July.  This leg of the cruise ends in Manila on October 3^rd but the Revelle continues on to Taiwan from there.  The captain heads for home on October 9^th, but he doesn't know his schedule after that and could be home as long as 3 months or called back out to sea pretty soon after getting back on dry land.  I asked Wes if he could have one thing named after him and he immediately replied, "A seamount!  Definitely a seamount.  And definitely not a reef.  You can write that part - definitely not a reef." 

Matt and Wes at the helm of the R/V Revelle

      We chatted next about life at sea.  You always hope for smooth sailing, but sometimes the unexpected happens.  I asked the captain what the scariest thing was that had ever happened to him at sea.  "Blog interviews," the captain replied.  Seriously though, Wes said that when weather turns, that can be tough.  It's rare to unexpectedly run into really bad weather these days, thanks to technology, but occasionally storms can creep up on you.  Once the winds pick up to 60 knots or so, things can get a little hairy.  Scripps vessels have also been involved in some civilian rescues, including an abandoned sailboat and a sailboat that had run aground near Palou.  In the latter case, a family with two young kids was brought on board the R/V Melville for a few days until the ship reached port.  The captain assured me the anti-pirate water cannons had never been fired…except to test them…on over-curious scientists.  
      Speaking of over-curious scientists, I asked if there had ever been any really strange requests from scientists, and Pete chimed in with a story about one researcher who was adamant about exactly where he wanted to drop a buoy off a few hundred meters off to starboard, in spite of a very shallow and very obvious reef, and in spite of the captain trying to point out that a large research vessel can't just sail over a reef.  You can bet the captain won that argument.  Wes shared that he has sailed with and shook the hand of Bob Ballard (and hasn't washed it since), who is noted for his work in underwater archaeology, and with Roger Revelle's wife on the maiden voyage of the R/V Revelle. 

      Finally, with the hopes that maybe some future marine scientists would be reading this blog, I asked the captain if there were one thing you'd want scientists to know before they came onto a research vessel, what would it be? 
       The unanimous answer?  "How to make good pot of coffee."

by Kelly Gibson

Actually, it's spelled "Kasten" core

"Kasten," of course, is a German word that means "Chris should check
his spelling before posting to the blog."


Here's a seismic line from our first survey that didn't post before.

Posted by Chris

Seismic Surveys

Ok. Whew. Busy couple of days. Last night the A-Team (some of whom are
at this very moment watching the disappointing movie remake of their
namesake tv show [full disclosure: so am I]) deployed the full monty
of cores, including the rare and elusive casting core, which we'll let
them tell you about later. Yesterday we spent most of the day shooting
a seismic survey for an IODP proposal, which is of course the reason
we're actually here. This is a much lower-key process than coring, in
that we spend most of the time monitoring the survey from a bank of
computers in a nice, air conditioned lab. This doesn't make it any
less complicated or nerve-wracking, however. The last couple sites we
surveyed didn't fit the bill.

First we have to run a multi-beam sonar survey of the ocean bottom. We
want to find a spot where the seafloor is flat, which suggests
flat-lying sediments. Multi-beam sonar is pretty cool, and provides a
detailed bathymetric map of the seafloor (bathymetry is like
topography, but underwater). The map at the top shows the bathymetry
of our survey site yesterday; warm colors are high seafloor (shallower
water) and cool colors are low seafloor (deeper water). On the right
side of the image you can see a broad flat area with our ship track
crossing it in a hatch pattern. That flat area looks like an
attractive drilling target, so we deployed our seismic gear. This is a
long process that mostly involves several of us standing on the fan
tail helping the seismic streamer through the block as it unspools and
attaching "birds," computer-controlled devices with dive planes that
can keep the streamer at a constant depth, which is important when
processing the data. Finally we lower the air guns into the water, and
we're ready to go.

Maybe we should back up and explain how/what seismic survey is. A
seismic survey uses sound to image the sediments under the sea floor.
As you can clearly see in the text-book quality diagram above, we
shoot off an air gun in the water at a set interval of time, and the
sound waves move through the water column and bounce off any surface
where the sonic impedance changes. A long stream full of hydrophones
trailing behind the ship picks up the reflected sound waves. If we
know the interval between the sound waves and the velocity of the
sound through the water column and through the sediment, we can
accurately map features below the sea floor. Some waves bounce off the
sea floor; some of the waves continue through the sediment and are
reflected at places where the sediment changes. These are usually
bedding planes. Seismic can resolve geologic features at a scale of
10s of meters, so large channel fills, onlapping or cross-cutting
bedding, and faults are all features that readily pop out. These are
all bad for scientific ocean drilling. We want flat-lying, boring
sediments with no erosional features so we can get uninterrupted
records of changes through time. This is the opposite of what you'd
look for in petroleum exploration, where complicated stratigraphy can
form traps for oil that make attractive drilling targets.

In the past few days we have completed two seismic surveys. The first
survey was disappointing at first, as it revealed that there was very
little sediment. The reflectors indicated that there was only a little
more than 50 m of sediment bounded below by a large reflector of
basement or volcanic rocks. However, as the survey continued the
sediments began to get deeper, and we ended the first survey with
about 150 m of flat layered sediment. The sediment was good enough for
coring at this location. One problem with this survey was that towards
the end, the marine mammal observer spotted whales close to the ship
(pilot whales and spinner dolphins, I think). In order to shoot
seismics there needs to be at least one observer to make sure that
marine mammals are not harmed by the loud noise the air guns create.
If a marine mammal is spotted within a certain distance of the ship,
the guns must be shut down, as occurred here. After the whales passed,
we were allowed to resume shooting. On top of that problem, the
compressors that create the air for the air gun broke down, which
meant that we had to shut shooting down again and wait for the
pressure to increase. The engineers have been working night and day to
keep the compressors going, yet the compressors seem to be the largest
problem with collecting data so far. Despite the ups and downs of the
first seismic survey, the second seismic survey proved to be a much
better success. There were points where we were able to see almost a
kilometer of sediment, which is great for coring! All aboard were very
happy with the second collection of data. Chief scientist Greg
Mountain even went as far as describing the incoming data as beautiful
and gorgeous! That means it must be good. Hopefully we will have the
same if not better success at our next four seismic survey sites. As
long as the compressors hold up, we should be ready to shoot!

Pictures:
1) multibeam sonar bathymetry of the survey area (note ship track with
crossing lines)
2) super awesome and well-drawn cartoon showing how seismic works

Posted by Chris and Kim

An Open Letter to the NSF regarding the renewal of the IODP

Well, I just e-mailed it to them. Is that what an open letter is?
Where you just e-mail it to them and then post it somewhere else for
everyone to read? Anyway, for those of you who don't know, the
Integrated Ocean Drilling Program is in danger of being cancelled by
the NSF, which would be awful for climate science, and geosciences in
general. The IODP is earth science's version of CERN or the Hubble
Telescope. Many of our biggest discoveries in the last 40 years are
directly related to the IODP and its predecessors.



September 15, 2013

Cora Marrett, Acting Director, NSF (cmarrett@nsf.com)
David Conover, Director, Division of Ocean Sciences (dconover@nsf.gov)
Roger Wakimoto, Assistant Director, Directorate for Geosciences
(rwakimoto@nsf.gov)

Dear Drs. Marrett, Conover, and Wakimoto,

I am writing to urge you to renew the Integrated Ocean Discovery
Program. The IODP and its predecessor programs have generated some of
the most important data in geosciences over the last 40 years. The
Deep Sea Drilling Project was first created to confirm the theory of
plate tectonics, and scientific ocean drilling has been quietly
revolutionizing the earth sciences ever since. Ocean Drilling has
provided the vast majority of the paleoclimatic record over long time
scales at high, including rapid changes that provide insights to our
current changing climate. The geologic time scale has been greatly
refined by ocean drilling data, including magnetic reversals in the
crust, orbital cyclicity recorded in sediments, and micropaleontology.
Unique and otherwise unobtainable datasets have also been generated
for, among many other things, the study of earthquakes and tsunamis at
crustal boundaries, the structure and petrology of the sea floor,
subsea fluid flow, previously unknown deep-biosphere communities, and
the structures generated by and processes of continental rifting.
The best records of change in the biosphere, lithosphere, hydrosphere,
and cryosphere over the last 200 million years are preserved in ocean
sediments and can only be accessed by scientific ocean drilling, and
there are still many research questions that are still unanswered.
Many of these are questions we haven't even thought to ask yet, and
will require new and specially designed studies to answer. Existing
datasets and samples are a limited resource and not adequate for all
research topics. Ending the IODP would be a mistake that would set our
science back indefinitely. Paleoclimatology would be hit particularly
hard; it is critical to understand the past in order to prepare for
the future. Without ocean drilling samples we would be able to do
neither.
I am writing you while at sea, aboard the R/V Roger Revelle,
conducting a site survey cruise for an IODP proposal to investigate
the evolution of the Western Pacific Warm Pool, which plays a critical
role in modern climate, particularly El Niño. That scientific
objective is very important, but this cruise is equally important to
me in my professional development as a research scientist. I am here
along with a nine other graduate students and post docs to learn the
skills to design and conduct shipboard research. The experience has
been amazing, and I have loved every second of it. This is a passion
for all of us aboard, and for many of our peers.
It might be selfish to ask you to renew the program because it is
something I am excited about, or because my professional prospects
will be curtailed. Those are valid reasons none-the-less, and they
certainly complement the myriad of scientific needs that demand
renewal. For the sake of our science, and those of us who are
passionate about this work and want to build our careers on it, please
renew IODP.

Cordially yours,


Chris Lowery
Ph.D. candidate
Department of Geosciences, University of Massachusetts

Piston Coring

I never imagined how high stress and anticipation sediment coring would be. Well, part of it. The way the scenario always played out in head involved a free-falling pipe with a ton of weight driving it in into the bottom of the ocean, cranking the pipe back up, and then followed by a mud celebration. Which is sort of what the multi-core and gravity is like, minus the free-fall. These cores are slowly lowered and slowly raised, returning full of mud if there is enough sediment and if it is soft enough to penetrate easily. 

The piston core is a whole different story. First of all, I could never seem to fully appreciate the size of a 50 ft piston. I've worked with 50 ft piston cores in the lab before - 10 sections, five feet each. No big deal. I guess i never thought about piecing them all together into one continuous core. I did today! And 50 ft is long, man! Long. 

Deploying the piston core takes a bit more effort. And by a bit I mean a lot. First, 50 ft of core liner is pieced together, then its inserted into a steel collar. The prepped piston core is then slowly lowered into the water horizontally until a safety trigger breaks and the core becomes vertical. Its really quite dramatic. I'll take a picture next time. A smaller gravity core is then attached to the larger piston core as a trigger. So when the trigger core touches bottom, it releases the piston core which is suspended slightly higher into a minor free fall into the sediment. 

The closest thing I can think of to compare the feeling of recovering the piston core is NASA landing a rover on the Martian surface. No, really. As the core is lowered, everyone's eyes are glued to the payload tension. A steady 4000 lbs as the core is lowered, then zero when the piston core is released by the trigger into the sediment. I still remember what our coring tech, Paul, said about the cable tension when we began retrieving the piston core - "…10,000 pounds - we're good. 14,000 pounds - we start to get nervous. 18,000 pounds - we release the cable and live to try again"

Watching the cable tension is our 7 minutes of terror. Seriously. 4000 lbs… 5000… 7000… 10,000… 14,000… 15,687ahhhhh!!!… 10,000… 8000… 8000… phew. We have a sediment core! Celebration for science! Quick, now lets extrude it and section it.

So far we've been pretty good at it. 5/5 pistons last time I counted. I think NASA's record is something like that too. 

Lowering the piston core into the water

                                                                                              

----Angel