Using GIS to aid in the search for underwater wrecks

Large amounts of data of varying types are collected during shipwreck search operations. Several geographic information system (GIS) packages (including ArcInfo, ArcView, and their extensions) were used to quickly and efficiently view, overlay, query, analyze, and interpret these data during a search for wreckage from the Battle of Midway. GIS software, ArcView Tracking and 3-D Analyst, were used during this survey to evaluate the potential of using GIS real-time and in a 3-D environment during underwater operations. In September 1999, ship time became available in conjunction with another survey to verify the backscatter imagery of the potentially man made objects found on a May 1999 survey. A high-resolution sonar towfish equipped with optical sensors was used. During the search operation, real-time navigation was displayed over data incorporated into the GIS from the May survey and newly acquired data. Using GIS increased the efficiency of the decision-making process, which was essential to ensure a successful short duration operation (less than 5 days). By using GIS in the decision-making process, all potential target sites were verified. A section of the superstructure of a ship and other shipwreck debris were found in one of the potential sites. The other sites were geological