Science Notes by Ahmet Arduc - Mapping a Shipwrecks Site
1. Planet Ocean
2. Mapping the Ocean Floor
3. Historic Shipping Routes
4. Sink or Float?
5. Navigating with a Compass
6. Navigating with a Quadrant
7. Water Depth and Pressure
8. Working Under Pressure
9. Interpreting Artifacts
10. Mapping a Shipwreck Site
by Ahmet Arduc – www.ahmath.com
Q: What happened to the beans as you continued to slosh the
water around in the tube? Did they stay in one pile at the bottom of
Mapping a Shipwrecks Site
A: The beans scattered across the bottom of the tub.
Shipwreck sites often cover large areas. Surface and underwater
currents and rough seas can carry shipwreck materials over great
Q: What is Pre-disturbance survey?
A: The first task of a marine archaeologist after locating a
shipwreck site is to document the site as it appears in its untouched
state. This documentation process is called a pre-disturbance
A pre-disturbance survey records the surface appearance of the site
before it is excavated. During the survey a map is made of the site,
showing the number, size, location, and orientation of the artifacts
as they are found.
Archaeology is the study of past cultures through the
of the material remains of those cultures.
is involved in
that it has
excavation of a
“Black Swan” in
location in the
A pre-disturbance survey involves recording the
of the artifacts found at the site, mapping their
• Noting any other characteristics that may be important to the
investigation and which may be lost once excavation begins.
Q: How big an area is represented by the entire map?
Q: What can be found at the location (9, 8), (10, 3), (5, 2)?
Q: What is ballast?
A: Ballast is heavy material placed in the bottom of a ship to make
the ship ride lower in the water and thus make it more stable. In 17th
century wooden sailing vessels, rocks were often used for ballast
when the ship was not fully loaded with cargo.
Ballast water loading
Cross section of
a typical galleon
design. Note the
two gun decks,
in the lowest
hold and the
that were critical
to the ships
stability and one
of the key ways
this very day.