November 19, 1995
Location: Bransfield Strait near Livingston Island
Update:
It was yet another long night of ZAPS work by the OSU team as they
continued to experiment, collecting more data and water samples in their
search for hydrothermal vents in the area. Each day they attempt to uncover
more information about the hydrothermal activity on the sea floor below. As
they collect more data it is like they are adding the missing colors in a
paint by number picture. The more data collect, the easier it is to
understand what the picture represents.
They finished the morning with another dredge. This time they collected a
few rocks and some sediments. In the sediments were a variety of bottom
dwelling organisms like sea squires and worms. It is like Christmas for me
as I wait to see what special biological packages are going to be waiting
for logging and preservation when the dredge makes it on deck. We collected
ten more specimens, bringing the total number of organisms preserved to
thirty six.
We left the ZAPS site and headed east to do some single channel seismic
work. The single channel streamer is much shorter and easier to deploy than
the multi channel streamer. It is only a couple hundred meters long and has
only a dozen or so hydrophones. Instead of six air guns used with the multi
channel streamer, the single channel only requires two. We spent the day
doing Sea Beam maps and seismic survey. The seismic survey provided the
scientists from Texas with some exciting information about the structure of
the earth's crust in this volcanic area.
At about 2:00 PM all persons left their stations for our weekly fire drill.
Once a week, all hands have to report to their designated areas no matter
where they are on the ship, or what they are doing. We usually head to the
03 deck where the life boats are, but today we had to go to the helipad on
the aft deck. The temperature was about 37 degrees F. and the wind was
relatively calm.
All of us had brought our survival suits and life jackets as required. The
first officer on the ship called everyone together and took roll call of all
the science and support members on the ship. We have to sign in on the log
to verify that we were at the drill. If people fail to sign in, a fine can
be levied against the ship. The helipad is the location that we would go to
in the event of a fire on the upper decks.
All of us were prepared with hats and gloves, but few of us had jackets as
we came directly from our work stations. I had been in the bio lab, and I
just grabbed the pile that I have made in my corner cabinet with survival
gear. I will be sure to add a jacket.
These drills are essential in the event that a disaster on the ship occurs
and we have to abandon. The average temperature has been about 28 degrees F,
but the water temperature is 32 degrees F, with floating ice. Even in a
survival suit, a person floating in the ocean without a life boat would have
only hours to survive.
We have two covered life boats. There is enough room for everyone to sit
strapped along the outside and a row of seats in the middle. Emphasis is
placed upon ballasting the boat, rather than personal comfort. There is a
single community toilet in the middle of the boat, and enough rations aboard
for 20 people for about 15 days.
Everyone understands the importance of these drills and there is no
hesitation or grumbling even when people are awakened by the alarm bells.
We all realize that if something should happen out here, there are few if
any immediate opportunities for rescue. We would have to wait until a ship
could make it to the area, which could takes weeks in bad weather.
In sharp contrast to the frenzy of the fire drill, we spent the remainder
of the afternoon mapping an area near an ocean floor volcano that looks
like it has been split in two. This would be the location for the night's
ZAPS work. As we made our slow transits to map the sea floor, a call came
down from the bridge at 8:25 that whales had been sighted. I was on watch,
but Dick, my watch partner, took over the number taking responsibilities
while I raced up the six flights of stairs to the bridge.
When I got there Carol Chin and Cara Wilson from OSU were already watching
them with binoculars. Two humpback whales were feeding of the starboard
side. All that we could see at first was the end of their tail fins and the
steam and spray from their blow holes as they surfaced. As we continued to
watch they gave us a display that we will never forget. It looked as if they
were standing on their heads in the water, because the full length of their
tail fins stuck straight out of the water. They would then slap the water
with their tails creating great splashes. Their splashing was both graceful
and powerful. We talked about whether they were playing or feeding. No one
knew for sure, but it was great fun to speculate.
As we moved toward the away site for ZAPS, our whale companions
continued on with their activities oblivious of our departure. The sun was
getting lower on the horizon and we half hoped that they would follow up to
the ZAPS site so that we could enjoy their company. They didn't follow, but
the memory of their visit will be a memento of this cruise that none of us will
forget.
QUESTIONS:
WF HS: The temperature of the water has a great affect on all the sonar
and seismic gear used on the ship. Since measurements of the sea floor and
earth's crust are made by this equipment by recording reflected sound, it is
essential that the temperature of the water be known so that the sound
velocity can be accurately calculated. The speed of sound in water is not
affected much by pressure, but the speed varies greatly with change in
temperature. Failure to know the correct water temperature means that our
data which is sound dependent will have some degree of error.
Hydrothermal creatures do not feed directly on sulfur. They feed on
bacteria which use the sulfur to produce energy in a process called
chemosynthesis. Chemosynthesis uses sulfur as a source of energy for the
bacteria cells to do their life processes. In this dark cold environment,
sulfur acts like the sun in photosynthesis. It provides the energy for life
to survive. A food chain develops with smaller organisms feeding on the
bacteria, and larger organisms feeding on them until we reach the top of the
food chain.
We are not sure of how or why creatures adapted to a sulfur rich
environment. Currently, the best hypothesis is that sulfur based bacteria
were probably the first bacteria to exist. Recent studies have found their
bacterial spores nearly everywhere in the ocean. They become active and
grow when they locate a sulfur rich environment. Scientists believe that
the sulfur based organisms near hydrothermal vents may have evolved into the
organisms of today as the environment of the sea and land changed. Life
became based on the energy of the sun rather than energy from sulfur.
I have been taking video images and photographs that I will post on the web
page with descriptions when I return to the states. Due to the complexity
of satellite communications on the ship, it is difficult and expensive to
send large graphics files to the people that update the web page. I hope
that everyone reading the updates will continue to visit the web page to see
these pictures when I return in mid December.
WASDI: Thanks for the comments and support. I have heard that there are a
variety of lesson plans being written to use with the web page. I would
love to include them for other teachers to use with their students by
creating a new addition to this web page.
MB & JB: This cruise has been a tremendous experience for me. I truly
enjoy working with the scientists on the Palmer and the prospect of doing
research as an occupation is enticing. I enjoy working with students far
too much. One of the things that I miss most is being in the classroom. I
love science, but what I love more is sharing the excitiement of science
with students who want to learn and know.
