Thursday, January 26, 2012

0075 – Processes of ditch filling

Dog skull inside ditch 3 of Perdigões.

The nature and the processes of ditch fillings are central to ditched enclosures interpretation. Several elements can be analysed to try to understand those processes. One of them is fauna.

Usually, faunal remains are approached in terms of levels of articulated bones, present and missing bones, structure of the deposition of the bones, animals represented and other associated elements.

Recently, a study of faunal remains from ditches 3 and 4 of Perdigões enclosure done by Cláudia Costa (“Problem of filling the ditches 3 and 4 (Sector I) of Perdigões (Reguengos de Monsaraz”, Estudos do Quaternário, 6, APEQ, Porto, 2099/2010) based on stratigraphic analysis of faunal remains”) showed that the taphonomical approach is also quite relevant and that, together with the analysis of other present elements, can be a precious help to interpret the formation process of the fillings.

Here is what she says in the papers abstract:

“During archaeological intervention on sector I of Perdigões ditch enclosure (Southern Portugal), dated from the IIIrd mil¬lennium B C, a section of Ditch 3 and 4 were excavated. The ditches are parallel “V” shaped structures, excavated on local bed rock, of 1,70 m (Ditch 3) to 2 m (Ditch 4) deep.

The ditches were filled with a sequence of anthropic sediments with archaeological artefacts, mostly potsherds, and vertebrate fauna. The species present in both ditches are suids, the most numerous, followed by bovids (domestic, and an element of an auroch), ovi¬caprids, red deer, horse, dog/wolf, rabbit and hare. The anatomical representation is the opposite in each ditch: in Ditch 3 the most common elements are from cranial and appendicular skeleton, whereas Ditch 4 is filled mostly with elements from axial skeleton. This aspect linked with the specific spatial association of bones and other elements, as pottery or pebbles, with an unequivocal intentional organization, doesn’t seems to fit on the pattern of secondary refuse. The faunal remains seem to integrate the “intentional depositions” at least on some points of the sequence.

On both structures, faunal assemblages are more fragmented on top of the sequence, and on the base, faunal remains tend to be more complete. The transition of more fragmented to less fragmented bones is materialized by intentional depositions layers, unit 58 on Ditch 3 and unit 34 on Ditch 4. On the other hand, in some stratigraphic units, root etching was identified on bone surfaces. Root etching is linked to vegetation that settles on soil profiles top, on the early stages of pedogenic developments. The existence of this phenomena point to a discontinuous filling process of the two ditches, where stratigraphic units remain stable and exposed long enough to pedo¬genetic process begin. On Ditch 3, the assemblage from unit 58, interpreted as “structured depositions”, is one of the most affected assemblages by root etching, which means that after sedimentary formation and installation of “depositional structures”, the unit was exposed. The same unit was affected as well by a natural water channel that mutilates the unit’s surface.
The other natural taphonomical signatures are manganese oxide, which affects continuously all remains from Ditch 3, and in a low percentage Ditch 4, and carbonate calcium that particularly affects the base assemblages in both ditches. This aspect reveals the strati¬graphic stability of the sequence.”

Sunday, January 22, 2012

0074 – What’s inside?

Possible reconstitution of the wall of the inside enclosure of Castro de Santiago and of one of the inside huts.

Usually, inside ditched enclosure we only have negative structures, basically constituted by pits. Positive structures are rare or simply nonexistent.

On the contrary, pits are rare in walled enclosures (see here), but positive structures are common (whit some exceptions, such Fraga da Pena). But it is current to find walls or alignments of stones that are usually interpreted as hut infrastructures or stone pavements.

At Castro de Santiago (Beira Alta), inside the inner enclosure, two of those huts were identified where the bedrock makes a sort of basin, and they had central fireplaces built in a hemi hexagonal plan with three slabs.

Hut infrastructures at Castro de Santiago and actual parallel in Africa.

Hut infrastructures at Castro de Santiago.

Although the walled architecture and the use of rock tor formations is similar in Fraga da Pena (just 8 km north in the same valley), the excavations made there didn’t reveal any similar structures inside. Being alike, those two walled enclosures seem to have played different functional roles, although, in terms of social identity management, they might have had similar tasks (as I have argued elsewhere: Valera, 2007).

It is important to notice what’s inside an enclosure and what’s missing to start to give them names. Structures, material cultural, social practices evidences, etc. He must “built” contexts first. So, when we have a surface evidence of a stone wall or a geophysical image of ditches, we must be careful in interpretation. If the general plan of the architecture of an enclosure could give us enough information to develop some analysis and propose some interpretation and develop some ideas, the cases of Castro de Santiago and Fraga da Pena remember us that similar general architectures could enclosure quite different contexts.

Friday, January 20, 2012

0073 – Map of Portuguese Prehistoric Enclosures

This is a map in permanent updating. From now on, it will be available in a separated page, next to the bibliography ones at the top of the blog.
It is, of course, of free use. Citation of the blog is the only request.

Tuesday, January 17, 2012

0072 - Águas Frias ditched enclosure

Location: Alandroal municipality, Évora district, Alentejo, South Portugal)
Chronology: Late Neolithic
Bibliographic references: Calado & Rocha, 2007.

Plan of Águas Frias (after Clado & Rocha, 2007)

Águas Frias is an interesting enclosure excavated during the rescue program of Alqueva dam, but still to be fully published. Is located in the valley of the Lucefecit river, a tributary of the Guadiana.

It presents in the left bank of the river three apparently concentric ditched enclosures, designed by wavy ditches with “V” profiles, being the middle one more regular in plan than the others and presenting the outside one a complex sequence of negative elongated structures in the north part. Based on its archaeological material the site was dated from Late Neolithic (second half of the 4th millennium BC).

Because the archaeological intervention was done when the dam was already flooding, the Lucefecit was then much larger and it was impossible to know if the ditches go through the river to the other side and the enclosures would be crossed by the water stream, as it happen in other cases (Porto Torrão, in Portugal; Pijotilla in Spain).

Nevertheless, the site was interpreted as a village and the ditches as defensive structures associated to palisades which ended in the water borders, creating an image of a semi circular settlement.

Águas Frias model(after Calado, 2007, in

An interesting aspect, yet to be explained, is the way in which one of the ditches ends, presenting the extremity in a ramp filled with a stone pavement.

Image of the ditch end (after Calado & Rocha, 2007)

Wednesday, January 11, 2012

0071 - Enclosures mental images

Some Portuguese enclosures present designs that have patterns that are visually striking from above and as a whole (from an aerial picture or geophysics image, for instance). Just like, with the natural differences, the Nasca “land drawings”. But their builders and users didn´t saw those images (well, there is the question of the possible balloons in Nasca).

But, didn´t they?

Could sites like Xancra, Santa Vitória, Outeiro Alto 2, Monte do Olival or Perdigões not have a previous and spread mental image that the architecture was reproducing? In fact, we have the metal capacity of imagining and visually conceive what we actually cannot see. We built mental maps, for instance, and we can build mental plans, even without flying or drawing.

So, how really were perceived these enclosures in terms of their plans and designs? Could this perception of Xancra ever been formed in the mind of one of its builders or visitors?

Tuesday, January 10, 2012

0070 - Neolithic ditches and rectangular houses

Senhora da Alegria is a surprising and important site, by the combination of its location, structures and chronologies.

It is located in central Portugal, where the littoral platform gives way to the central mountains and in one of the pathways to the hinterland of Beira Alta central Portugal, where no ditched/palisade enclosures were known until now.

A sequence of occupations dating from Early Neolithic (with “cardial” decorated pottery) to Late Neolithic is being excavated by the Omniknos company (scientific coordination of António Valera and field direction of Tiago do Pereiro and Rui Ramos) in a context of archaeological emergency intervention.

The site presents several ditches, some of them probably corresponding to palisades, that form more than one enclosure, with several moments of construction with structures cutting other structures.

One of the ditches of the eastern side of the site.

Those ditches cut previous early Neolithic layers and some of them may be also from the same period and others from a middle Neolithic phase. These ditches are then covered by layers with positive stone structures, dating from middle/late Neolithic.

One of the ditches of the western side of the site, going under Late Neolithic layers.

It is, therefore, the earliest site with this kind of structures known in Portugal (and in this area of Portugal), revealing that also in western Iberia this architectures are present at the early stages of the Neolithic (as was already documented in eastern Iberia).

But it also present one (at the moment) rectangular house. Rectangular Neolithic houses are quite rare in Western Europe. In Portugal, for the recently excavated and published site of Castelo Belinho in Algarve (by Mário Varela Gomes), post holes were argued to be evidences of the presence of rectangular houses. Nevertheless, some scepticism has been revealed by some scholars relating those interpretations, because of the large and scattered number of post holes. But at the present site the image of the structure is striking and leaves no doubts: a sub-rectangular house (with slightly rounded corners), with central posts aligned with the entrance (facing east), with 10,5 x 5,5 meters.

Image of the house post holes.

One of the post holes of the entrance (left) and one of the central ones, reaveling two construction moments (right) .

So, this archaeological context also presents for the first time in Iberia the “association” of rectangular houses with ditches at a same site and gives strength to the interpretations developed for the Algarve’s site.

Located at in a hinterland transitional point, this site is already fundamental to the research of Neolithic process of West Iberia, to the emerging of the surrounding megalithism (and the Beira Alta one) and to the problems concerning the appearance of ditches/palisades enclosure architectures in the peninsula.

Not everything is bad news in this new year of 2012.

Friday, January 6, 2012

0069 - Topographical differences

I’m now writing the paper presented at the Rome conference, where the main issue was to compare ditched and walled enclosures in South Portugal, since they share the same general space and time.

I centred my analyses in eight aspects: tendency for architectonic separation; topographical location; dimensions; design ; architectonic dynamics and associated practices, cosmological foundation of architecture; relation to funerary practices; practice of metallurgy. Some of these items were already discussed here (dimension, presence of pits).

Today I would like to draw the attention to the topographical differences between the locations of this to kind of architectures. Those differences can be expressed as a more homogeneous location strategy for walled enclosures that prefers exclusively hill tops (or cliff edges or high rocky tors in central and north Portugal), and a more diversified location for ditched enclosures. We can find them also on hill tops (Santa Vitória, Outeiro Alto 2), but they can be in the middle of smooth slops (Xancra, Monte do Olival), in natural amphitheatres (Perdigões, Paraiso), in large valleys (Porto Torrão) or spread from small and flat hill tops, through the slops and to the lower ground (Moreiros 2).

In fact, ditched enclosures do not reveal a particular standard pattern of location. By the contrary, they relate themselves with the landscape in diverse ways, although we can observe some tendencies, like the interest of building facing east (frequently with gates astronomically orientated).

This difference between ditched and walled enclosures is just one amongst others, suggesting that, in general, they didn’t serve exactly the same purposes or, at least, that those architectures were responding and were related to specific practices that were not shared by both.

Monday, January 2, 2012

0068 - Plurality of funerary practices in ditched enclosures

Cremation experiment in progress (Tõnno Jonuks & Marge Konsa, “The revival of Prehistoric burial practices: three archaeological experiments”, 2007)

This is an issue that will be discussed in the becoming meeting on Perdigões research project, next February. There, new radiocarbon dates demonstrate that several different practices regarding bodies manipulations were occurring at the same time (according the method resolution capability) in several areas of the enclosure and in different structures.

The data that is being obtained at Perdigões, as I have said already elsewhere, demands new theoretical approaches to funerary practices in Late Neolithic / Chalcolithic, namely the ones that deal with the problems of the unity and ontology of the body and that develop relational conceptions of burial places and structures. The notion of necropolis, as a clear individualized space for the dead, is clearly at risk in Perdigões, as in other large ditched enclosures.