[N] 2006 Many fossil tracks do not represent \\\\\\\"true\\\\\\\" surface tracks.
Manning, P. (2006) Dinosaur track 3D geometry and demensionless speed. JVP 26(3) Abstracts pp.95
The underlying assumption of many track interpretations is that they represent surface features. Therefore, dimensional parameters (foot length (FL), stride length, etc.) on which speed calculations are based are interpreted as records of FL (sediment/foot interface). Laboratory track simulations coupled with observations of fossil tracks, casts serious doubts on the use of track length in such ‘calculations’ of speed. Dinosaur tracks are often used to calculate FL of a trace-maker. FL in-turn is used to estimate a track-makers hip height (h), when calculating the speed at which an animal was travelling, using a non-dimensional parameter, the Froude number, allowing comparison between animals of varying size using physical similarity theory. The resulting equation was written so that speed (u) is estimated from known values y (stride-length) and h (estimated by multiplying FL by 4).
Since the first application of this formula it was clear that if h were overestimated, u would be underestimated. Creating large discrepancies in speed from fossil trackway data is not difficult; for example, a track length of 0.10 m gives a hip height (h) of 0.4 m. However, if the 0.10 m track was a transmitted feature and the true foot length measured 0.07 m, h should have been calculated as 0.28 m, meaning speed (u) from the larger track would be underestimated in excess of 25%. Such error can easily arise from how a track is measured or by being an incomplete transmitted, under or over-track feature. The recovery of subsurface track layers from laboratory simulations provides a useful method to reconstruct the 3D subsurface track geometry and morphology for comparison with ‘true’ surface track features. Information gained from the laboratory track simulations confirms that many fossil tracks collected and described are transmitted features and do not represent ‘true’ surface tracks. This has significant implications for the interpretation, taxonomy and wider application of all fossil vertebrate tracks.