To aid in the correlation of deep refractors in the Frome Embayment, a series of eight seismic refraction velocities were determined on the Proterozoic and Palaeozoic outcropping sections in the Blinman-Wirrealpa area of the Flinders Ranges. The velocities range from 10 100 ft./sec. in the Grindstone Range Sandstone to 19 500ft./sec in the Wilkawillina Limestone. Correlations between deep refractors and sections down to Lower Cambrian are suggested.