GEOPHYSICAL AND REMOTE-SENSINGSURVEYS 113
300 m (975 ft). AUVs, as their name suggests, are
autonomous systems that function without remote
control, tethers or cables. Their depth-rating at the time
of writing is restricted by battery-life to approximately
3000 m (9750 ft).
Aerial Photography
Aerial photography, particularly using modern digital
cameras, is a successful method of investigation for
inter-tidal and foreshore research but has limited success
in underwater research due to an inability to penetrate
the water column successfully beyond, typically, 1 to 3 m
(3 –10 ft). Modern high-resolution digital cameras pro-
duce images in either colour infra-red (false colour)
or true-colour mode. The size of the ground covered
by each pixel can range from 10 to 50 cm (4 –20 in) and
above, depending on flying height and speed. Although
this pixilation does not give images as obviously detailed
as conventional film, digital images are easier to rectify
and analyse.Further Information
Boyce, J. I., Reinhardt, E. G., Raban, A. and Pozza, M. R., 2004,
Marine Magnetic Survey of a Submerged Roman Harbour,
Caesarea Maritima, Israel, International Journal of Nautical
Archaeology 33 , 122–36.
Dean, M., 2006, Echoes of the Past: Geophysical surveys in
Scottish waters and beyond, in R. E. Jones and L. Sharpe (eds),
Going over Old Ground – Perspectives on archaeological
geophysical and geochemical survey in Scotland, 80 – 87.
BAR British Series416, Oxford.
Fish, J. P. and Carr, H. A., 1990, Sound Underwater Images: A
Guide to the Generation and Interpretation of Side Scan Sonar
Data. Boston, MA.
Papatheodorou, G., Geraga, M., and Ferentinos, G., 2005, The
Navarino Naval Battle Site, Greece: an Integrated Remote-
Sensing Survey and a Rational Management Approach,
International Journal of Nautical Archaeology 34 , 95 –109.
Quinn, R., Breen, C., Forsythe, W., Barton, K., Rooney, S. and
O’Hara, D., 2002a, Integrated Geophysical Surveys of The
French Frigate La Surveillante(1797), Bantry Bay, County Cork,
Ireland, Journal of Archaeological Science 29 , 413–22.
Quinn, R., Forsythe, W., Breen, C., Dean, M., Lawrence, M. and
Liscoe, S., 2002b, Comparison of the Maritime Sites and Monu-
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study from Rathlin Island, Ireland, Geoarchaeology17.5, 441–51.
Quinn, R., Dean, M., Lawrence, M., Liscoe, S. and Boland, D.,
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