18 November, 1995

November 18, 1995

Location: Bransfield Strait near Livingston Island

Update: Ship time is split nearly evenly among the two science groups these past few days as both of the science teams try to get as much data collected as possible during our time here in Bransfield Strait. For the geophysicists from the University of Texas that means Sea Beam mapping of the sea floor. For the geochemists from Oregon State that means more vent sniffing with the ZAPS sled. The change from Texas time to OSU time happens about 8:00 PM each day during the middle of my watch.

Changing science time zones is often a hectic ordeal. Dick and I are responsible for making sure that the shipís bridge has the proper coordinates to get to the starting point for OSUís night of data collection, after a day of mapping. We are also trying to get every last contour line on the map of the day as we make way for the ZAPS starting point.

The map that was made today during our survey covers an area 15 miles x 15 miles near Livingston Island. These large contour maps of the sea floor maps are made using a technique called mowing the lawn. The ship starts the pattern by following a direct course in one of the four directions. As the ship travels a continuous contour map of the sea floor below is made by the Sea Beam Sonar system. At a predetermined distance, the ship makes a 180 degree turn and heads in the opposite direction. It is the job of the watch standers to give the bridge subtle course changes so that the contour tracks of the sea beam overlap one another just slightly so that a continuous map with no empty spaces is made.

This back and forth pattern is like mowing the lawn. The blank spaces on the map are like the grass that was missed while cutting the lawn. Like a lawn, the sea floor isnít always level, and you donít always walk a straight line. The same holds true for the ship. We spent 8 hours doing this map with each back and forth swath taking about two hours.

The resulting map is beautiful. We have very few open spots except near the turns which are very hard to make with such a large ship. We were able to identify some very interesting ridge formations and small volcanic features. Most of the area is gradual sloping planes with an occasional formation jutting out from the sea floor.

The OSU team continues to accumulate data. Sometimes we forget that for scientists the absence of change is also important information as well. The ZAPS drift tonight helped the OSU group focus their search by eliminating areas that obviously lack the characteristics that are typical of vent zones.

The whole process of doing science on in in the field, as we are doing on the Palmer, takes time. Work periods are typically 14 to 16 hours long for the scientists on board. Science, especially science on a research ship is not done by the time clock. Science is done for as long as the data keeps coming in and the equipment and people can keep working.

We did take a few breaks to enjoy the scenery today. As we made our map, we traveled along the coast of Livingston Island. Livingston is a volcanic island with black basalt rock cliffs and outcrops jutting out of the snowy mountain slopes. The clouds play hide and seek with the mountain tops, as they peak in and out from among the pointed crests, pushed by the sea breeze.

The shoreline is steep and rugged marked by sharp vertical cliffs and pyramid shaped projections. These pyramids of rock are like rows of teeth protecting the coast, ready to chew any incoming ship that strays to close to its banks. The island looks like an artistís pen and ink drawing. The black rock defining the mountains outline in the white blanket of snow drawn on the canvas of sea and sky. As the sun began to set, the island cast shadows across the water that changed shape as they moved on the waves.

Antarctica is a beautiful place. Each day is like entering a new room in a museum. Each dayís brings us a new exhibit in this Antarctic museum that is inspiring and unexplored.

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