The refraction seismic tests described in this report were made at the request of the Victorian Railways Department. The work was located within the railway reserve between the outskirts of Wodonga township and the River Murray, and consisted of the shooting of five refraction traverses, set out approximately parallel to the railway line and covering in detail a total length of 4,800 feet. The aim of the seismic work was two-fold. Firstly an investigation was required of the subsurface formations in the vicinity of the bridges which carry the railway across several creeks intersecting the Murray flood plain. The subsurface information is required in connection with the design of the foundations of new bridges which will be constructed to replace the existing ones. The second purpose of the work was to test whether the refraction seismic method would be suitable for adoption by the Railways Department engineers as a standard routine method for investigating foundation conditions. To fulfil this purpose ideally, the method would need to be applicable generally to all the foundation problems encountered by the Department and to completely eliminate the necessity for test drilling of sites. The flood plain of the Murray, on which the seismic measurements were made, is composed of Recent alluvium, probably underlain by Tertiary river deposits and is crossed by several creeks and anabranches of the main stream. The outcrops in the vicinity of Wodonga show the bedrock to be granite and metamorphic sediments. The field work was done between February 26th and March 12th, 1953. The field party comprised two geophysicists and three field assistants provided by the Railways Department.
