20th November 2005, 01:44 PM
Quote:quote:Originally posted by BAJR HostRat,
it must be repeated in several areas, by other people to see if the test can be replicated... glass balls are loose, the matrix is different, etc etc.
As an initial investigation I find the results of the plough damage experiment to be very interesting, but can see scope for refinement if similar experiments are undertaken in the future (which I hope they are). Paul Barford?s comment (britarch) on compaction which you also allude to is a valid one, though given the fact that multiple blades are attached to a single boom of the plough, I presume that the degree of ?bite? will be dictated by the overall compaction of the ground across the length of the boom. If the other blades are travelling over compacted subsoil/natural, effectively supporting the blade that encounters the soft spot, then the effect of one small soft spot should not alter the distribution of marker artefacts to a high degree. This cannot be said of larger features or backfilled evaluation trenches.
Because the feature was backfilled purely with beads, recompaction was impossible. Future experiments might consider mixing the marker artefacts with material derived from the feature, which could then be compacted to the same level as the remaining fill. A further refinement might also be to use marker artefacts of different colours at different depths. There is certainly scope for further work, and it will be interesting to return to the current investigation area after the next ploughing to see if beads are dragged up from the backfilled features.