Resurvey

This week on the Western Argolid Regional Project, I’ve been running a few queries that compare the data from our original survey field walking and subsequent efforts to expand the assemblages present in these survey units. We termed these later efforts “resurvey” on WARP and thought they might be useful both to expand our generally small assemblages into something a bit more susceptible to functional analysis and to calibrate our recovery rates (as David Pettegrew and I did on the Pyla-Koutsopetria Archaeological Project). 

The challenge with this kind of analysis is how do we compare two different assemblages. In general, these two assemblages did not produce the same specific types of artifacts on the basis of our narrow typologies (i.e. the odds seem small that we’d find, for instance, two examples of the same African Red Slip form or even two examples of a Classical cooking pot), so that is not a very useful way to compare things. 

To open up the potential for meaningful overlap, I did a quick comparison of our resurvey units and our initial survey units to see if they produced the same period. This involves comparing the exact periods present in the finds from our first walking of the units to those found in either re-walking the units or in total collection circles with 2 m radius. Generally speaking there was some overlap between periods from each collection type. A few units producing over 50% of the material from the same periods, but most resurvey units produced material that had much lower overlaps (10%-20%). In this context, overlapping periods represent specific chronological period overlaps, such as Classical or Early Roman. This does not account for overlaps that are more broadly defined, such as when one assemblage produced Classical pottery and the other produced Classical-Hellenistic.  This is the next step in analysis is to see if resurvey produced chronological (as opposed to simply period) overlaps. This is a more complicated query and not ideal for analysis in the field.

We also compared the artifact densities per hectare from the resurvey units and the original survey units. As we demonstrated on PKAP, looking more carefully at the ground produced significantly higher densities. The highest density resurvey unit – which consisted total collection circles with 4 m diameters – produced densities that were over 100,000 per ha, for a unit that produced a density of only 1,700 artifact per ha through standard field walking practice. (Despite this massive difference in density, the unit produce a period overlap of over 50%!). Other units showed a similarly massive increase in densities with the resurvey units often producing nearly the same amount of pottery as the original survey units which covered much larger areas.

The differences between the two densities likely reflect three trends. First – and most obviously – a team of two or three scouring a 4 m diameter total collection circle for 10 minutes is like to find more pottery than a field walker, standing upright, and scanning 1 meter to either side even at a leisurely pace. Total collection circles were also much more likely to be placed in high density areas. After all, part of the goal of resurvey was to produce more a robust assemblage of material for chronological and functional analysis. Finally, total collection resurvey circles tended to be in areas of the unit with higher surface visibility. For each survey unit we recorded the average visibility for the entire unit. We did the same for the total collection resurvey units and they generally were 20%-40% higher visibility than the original survey units.

In the end, my analysis of these units is just starting. Considering the functional character of the original and resurvey assemblages, the chronological overlap of the two sets of material, and whether they produced new information about the   

One Comment

  1. Did you also/ever resurvey empty fields?

    Reply

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