Figure 3. Variation in colour of Broome Sandstone and its sauropod dinosaur tracks.

A, freshly-exposed and conspicuous example of a pes (hindfoot) print; the thinly layered sediments are characteristic of lagoonal substrates in the Broome Sandstone, though the vivid coloration is often subdued by weathering; scale is 1 ft (c. 31 cm) wooden ruler. B, pes print impressed in, and filled by, blue-grey siltstone; examples such as this are difficult to detect when sea-water has evaporated from the erosion pits along the interface between cast and mould; scale indicated by camera lens cap (diameter 6.7 cm) at lower left.