The former slaver James Matthews was wrecked in 1841 at Woodman Point, in Cockburn Sound, Western Australia – the night after the ship arrived following a four-month voyage from England loaded with supplies, passengers and equipment for the Swan River Colony.

The wreck, discovered in July 1973 by members of the Underwater Explorers Club, now lies buried in sand about 100m offshore.

Supported by the WA Museum (WAM), MAAWA and Acoustic Imaging Pty Ltd (Doug Bergerson), the Winwell Foundation aims to create, evaluate and optimise 3-D visualisation modelling of buried underwater heritage remains, based on a high resolution SBP (Sub-Bottom Profile) survey across the James Matthews wrecksite.

We have recently completed the high-resolution 3-D SBP survey of the wrecksite (see News Stories page) using a vessel-mounted multi-head SBP transducer traversing pre-programmed parallel survey lines separated by 1m spacing. Given the unusually windy conditions, this was a tougher assignment than anticipated!

With four fixed transducer heads spaced 25cm apart, this has resulted in a high-density survey, shown below, with more than 200 closely-spaced parallel acoustic echo traces over the immediate area of the known wrecksite boundaries, and further beyond (thanks to Doug for supplying this image).

The resulting acoustic data will be extracted and visualisation packages tested, manipulated and optimised to present the results in 3-D virtual format.

These will be compared and evaluated against the 3-D model of the excavated remains based on overlapping photography taken during the 1976 WAM excavation survey, as well as the 3-D AutoCAD model generated from this survey and a 2017 course-scale SBP acoustic survey (also depicted below).

Representation of the multi-line SDP data in 3-D visualisation software will hopefully provide WAM, practitioners and the public a means for non-technical experts to visualise material buried in the seabed – in this case, the wreck of the James Matthews.

It is anticipated that the results from this research will also provide maritime archaeology practitioners with optimised processes and guidance notes with which to collect and analyse SBP data, whilst at the same time providing additional confidence in the use of SBP acoustics to map and interpret sites with sub-seabed cultural heritage materials.