Carrascal (Porto Torrão) ditch excavated by ERA Arqueologia (responsibility of Helena Santos)
I frequently remember the name of this song when I think about all of the geological material that was extracted in the processes of building ditches. Where have all the tons of geological material gone?
As I’ve said before, we completed this year a cross section in Ditch 6 of Perdigões, dated from Late Neolithic. This, combined with the plan obtain by geophysics, allows us to estimate the volume of bedrock extracted. Assuming similar shape and measures (sometimes they change along the ditches) of Ditch 6, that has almost a two hundred meters perimeter, the building process implied the excavation and removing of about 745 m3 of geological material (I will also calculate the weight).
I will deal later with the questions of logistics, labour and technical problems. For now I just renew the question: where is it?
Traditionally is assumed, I repeat assumed, that bank walls were built with that material, later eroded. The problem is that there are no evidences of that erosion in any of the already surveyed ditches at Perdigões (as in other Portuguese enclosures). They simply are filled with different materials (with exceptions for small erosion of ditch walls, as we can observe in a specific point of Ditch 6).
But the geological is also not outside the ditches, not even in Perdigões, that is topographically an amphitheatre, with the pendent orientated to the inside and East. Ditch 6 is in the centre of the natural amphitheatre. If there was a bank by the inside of the ditch built with the geological material there should be evidences of it. There are not.
If we think that at Perdigões are at least 11 ditches, progressively bigger than Ditch 6, we start to have an idea of the quantity of geological material removed there over time. Thousands of cubic meters; thousands of tons (it is now possible to also estimate the volumes for ditches 1, 3 and 4).
Where is it?
It seems that your findings in this aspect are having an impact a year later:
ReplyDeletehttp://www.publico.pt/Ci%C3%AAncias/estatuetas-descobertas-no-alentejo-tem-4500-anos-e-cabem-na-palma-da-mao-1558397?all=1
http://terraeantiqvae.com/group/prehistoria/forum/topics/descubren-estatuillas-de-marfil-de4-500-anos-de-antiguedad-en-per?xg_source=activity
http://asociacionlosdolmenes.blogspot.com.es/2012/08/portugal-descubren-estatuillas-de.html
(All links in Portuguese or Spanish language).
Is it correct that these idols are so rare in Portugal when they are common in many areas of Spain? One would have though that the modern border did not exist back then and that in fact SW Spain (Extremadura, West Andalusia) was much more related to Southern Portugal back in the day, so I am a bit perplex by this claim. Care to qualify?
Well that is natural, since we make every year a press conference in the field to present what is being excavated a the results of the previouse campaign. And we presented last year figurines as well as this year ones. The context of cremations is still in excavation, and will be the next year. So, more is to be expected from there. And if you follow the blog of the excavation you wil see that in the last day, new idols were found in a diferent context.
ReplyDeleteAs to the relation to Andaluzia and Extremadura, there is a strong connection with Alentejo and Algarve, which is also natural as you poit out. But the fact is that those antropomorphic figures were totaly absent from South Portugal until now. What does that meen? Probably a problem of research. Those figurines tend to appear in large enclosures and Perdigões is the only one being systematicaly researched in South Portugal. Or maybe not. Some other iconic materials (like the schist plaques or the painted bones) have clear regional distributions, even if they respond to wider ideological frames. Regional expressions of shared ideas.
Although there is a shared cultural ambience in South Iberia, Southwest presents its own particularities.