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Dispatch 12: Analysis Begins
October 6, 2000
[Note: Nationalgeographic.com does not research or copyedit dispatches.]
The following dispatch was supplied by Dr.
Fredrik Hiebert, Chief Archaeologist of the Black Sea
2000 Expedition.
Since the report of the discovery of the habitation
site (site 82) and its initial reporting the following
has happened: We were granted permission from
the Turkish authorities to move to a further stage
of investigationsampling and actual
testing of some of our observations. Thus, when
we went in and investigated the site further, we
found that suggested mud slabs were actually
stone, and that the suggested stone artifacts were
actually wood, etc. We now have samples from
the site which we collected. (They are in my
refrigerator at the moment.) I am sending them
for scientific analysis.
Scientific Method in Action
We are in the process of learning about this flooded
coastline. Every exposed rock and stone we see
was clearly part of the landscape when this was
dry land. It is very exciting to be the first to see
this landscape since it flooded. With the discovery
of this site, we now are in a position to fit it into
our larger picture of the ancient cultures of the
Black Sea area.
Archaeologists use the scientific method. Our
assignment of this site as an ancient habitation
site is a hypothesis. To test this hypothesis, we
first need to have a model (something which is
only partially known or unknown) in our heads of
what the objects we could see were, and how they
came to lie together on the floor of the Black Sea.
While the video images taken from the ROVs look
just like ancient structures that we had seen on
land, we had to consider other scenarios that could
have produced a similar arrangement. Other
interpretations that we must consider are that we
were observing a natural geological outcrop that
had accumulated wood over the years, a broken-up shipwreck, or even the debris from a
modern depth charge.
Our job as scientists is now to devise tests that
would allow us to exclude these interpretations
and/or to offer support to our hypothesis the site
was a human-built and used archaeological site.
Using still cameras, we compiled a photographic
map of all the features that we could see.
Armed with this tantalizing picture, we
approached the Turkish Ministry of Culture for
permission to sample the site for scientific
analysis. We were granted permission and the
Northern Horizon returned to the site
location. The opportunity to visit this submerged
site was the thrill of a lifetime.
Twist of the Depths!
We jury-rigged a special recovery device for
Little Herculesan experimental addition
that was put together on the boat.
It worked! We watched on the video while a
flexible probe touched and lifted some of the
objects. The texture, density, and shape of the
objects on the screen became clear as Little Herc
circled only a few feet above the Black Sea floor.
For now, this is the closest that we will ever get to
actually seeing the site with our
own eyes. Later, a sampling bag allowed us to
raise a few carefully chosen artifacts and other
objects to the surface for examination and testing.
In addition to these objects, we collected samples of
the mucky deposit on the surface of the site.
What did this device allow us to learn?
First of all, we found that the sedimentary blocks
that appeared to be clay are actually
stone, not mud. Second we retrieved
several of the artifacts, and they turned out to be
wood, not stone.
Many Neolithic and Bronze Age buildings have
such stone foundations, just as many have wood
and mud type architecture. We have to
understand that people in the past used many
types of building techniques, depending on the
situation (I like to use the Three Little Pigs
concept) during the same period. A culture can
build buildings out of sticks, brick and stone. It is
quite likely that the stones could have made a
solid foundation for a building that was partially
constructed under the ground, like a shallow
pithouse. This new hypothesis is based upon
learning from our testing and revising our model.
Following this new scenario, the original surface
might have been eroded by water to leave the
surface that we see today.
Our closer look at the wooden artifacts confirms
our first impression that they are the result of
shaping by humans. They have smooth,
symmetrical shapes and unmistakable traces of
drilling to produce the holes visible on the videos.
We dont know a lot about ancient wooden
tools since wood is rarely preserved in any form,
but we can compare these objects with the tools for
woodworking that have been found at sites on
land, and with wooden objects produced by
craftsmen in todays traditional societies.
Scientific Analysis Begins
With samples in hand, we rapidly developed a
plan for the analysis of materials that might
represent an ancient land environment but which
have also been in a cold, wet, Black Sea
environment for an unknown number of years.
Once we had consulted with an expert on
conserving waterlogged wood samples, we
proceeded with our highest priority, dating the
wood samples using the supersensitive accelerator
mass spectrometer (AMS) radiocarbon technique.
Only tiny samples are used for this technique. We
chose fragments of six worked and natural wooden
objects to submit to the laboratory. (Extracting
these fragments did not destroy the objects.)
One test of the integrity of an archaeological site is
whether a series of radiocarbon dates fall in a
cluster in time. If we are told that the dates are
quite recent, or represent a wide range of
dates, we will have to reconsider our hypothesis of
how the site was formed.
Dates will be reported to us in a matter of weeks.
In the meantime, we are reaching out to a variety
of scholars who we hope will be able to help us
understand what an undersea site might look like.
Using a new, refined model of what to expect if site
82 is an ancient structure, we plan to study the
artifacts and deposits at a number of levels. The
muck will be analyzed to determine its
microscopic structure, its phosphate content (a
signal for human occupation and trash), its
possible content of charred or waterlogged seeds,
bones, and shells, and any occurrence of pollen or
silica cell wall remains of crops or other land
plants. The wood itself will be identified and
compared to modern and prehistoric forest cover
in northern Turkey. At the same time, we will be
examining the contours of the Black Sea floor to
most precisely locate site 82 in its geographic
context, both during the period it would have been
on dry land, and since the time it must have
flooded.
Our visual fix on site 82 using
remote video technology was immediate and
compelling. Now, we are excited to be able to test
and evaluate our impressions, and to tie these
finds to our other research projects on ancient
Black Sea peoples.
Dr. Fredrik Hiebert Go to 1999 Dispatches
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