Title: A mamoa 1 de Chã de Carvalhal, no contexto arqueológico da Serra da Aboboreira
Description: SUMMARY

Barrow 1 of Chã de Carvalhal forms part of the megalithic complex of Serra da Aboboreira. It is situated in the westernmost part of the counterfort of Marão, on a gentle slope, near other monuments of the same type. The tumular construction stands out from the landscape quite impressively (especially if seen from the south), owing to its size.
The archaeological investigations of the monument in 1982 and 1986 have permitted a more precise description of the characteristics of the construction: an earthen tumulus, its surface protected by a very thick stone casing; circular in shape; measuring 13m. in diameter and 1.30m. at its maximum height (not taking into account the ground in situ, ancient burial soil, the depth of which varies between 0.40 and 0.60m.). Immediately above this structure (or in some cases, on an earthen layer formed over it), is an incomplete lithic circle. This is made of blocks and slabs of granite, of medium size and regular shape, which show signs of being finished or of having been carefully selected, but which have no technical function. In the central area of the monument (and of the lithic circle), stands the burial chamber: cystoid in type; sub-rectangular in shape (1.50 x 1m.); closed; composed of six supports not more than 1.50m. in height; reinforced by a counterfort on the exterior. Between this and the lithic circle, on the eastward side, there is a granite monolith, completely different in texture and configuration from the blocks from which it was made, resting on the superficial structure.
The preparation of the designated site (previously cleared of vegetation, perhaps through fire) and the regularity and symmetry of these different structures, indicate that there was a previously established and carefully executed plan. It is possible that even the very act of construction had been ritualized: the tumular "building" would have constituted a collective offering by the community, of the highest magnitude.
The scouring of the surfaces and the excavation of the burial chamber, as well as of the tumulus soil, by opening two boring ditches, allowed some objects to be collected: ceramic fragments, perhaps belonging to about 10 vases, some of them plain, sometimes quite coarsely made; others decorated and resembling the bell beaker in so far as the spotted band is concerned — international variety (Maritime type: Herringbone var.) —, "geometrical dots" and "notched" (Palmela and Ciempozuelos Complex); 2 tanged daggers and five spearheads (in copper with a high arsenic content) of various types; 2 granite "spheroids" showing clear signs of being finished, having peg marks. Only metallic materials were found in situ in the tumulus soil, near the burial chamber, distributed in two groups (daggers and spearheads) on the outer stone casing. The ceramics  came from the surface soil covering this structure, although the greater concentration, sometimes related, was collected near the granite monolith on the eastern side, as well as inside the lithic circle. This raises the possibility of ritual depositions outside the funeral chamber.
Barrow 1 of Chã de Carvalhal represents, technically, a symbiosis of archaised characteristics — common in dolmens — and innovative solutions, which place the barrow at the high-point of the megalithic movement in this region. The objects found are also from a later period, showing evidence of a mixture of different elements: some local in character; others exogenous. This indicates connections with the Calcolithic period or with Early Bronze Age.
The conjunction of the different elements allow it to be placed, within the context of the pre-history of northern Portugal, in the period of transition from the late Calcolithic to the Bronze Age, which the author places at around 1850 B.C. (in conventional chronology). On the other hand, there is clear evidence of external contacts, which would make possible the penetration of the bell beaker from the Portuguese coast and in a North-South direction.
The study of the monument has been complemented by pedological, pollination, anthracological, paleocarpological and metallographical analyses, the results of which are to be found in the appendix to this text.

The integration of Barrow 1 of Chã de Carvalhal into the local context requires an overview of the pre-historic settlement of Serra da Aboboreira.
Without taking into account the existing evidence of pre-megalithic settlement, data on which is as yet unpublished, all the information collected from archaeological excavations in the area of Serra da Aboboreira is compiled here.
As far as megalithic monuments are concerned, the valorization of different aspects (typology, dimensions, the location of the monuments in a particular place, material culture, megalithic art, radiocarbon dating etc.) allows the defining of distinct types of construction and their chronological location. This should be treated as an approximation, probable but still debatable; and provisional given the quantity and quality of information currently available.
The area of Serra da Aboboreira would have started to be used for funerary purposes from the second half of the fourth millenium B.C., with the construction of enclosed dolmens, of reduced usable space and having tumulus of medium size. The largest and most spacious monuments would  have been built at a later date, at the end of the fourth and the beginning of the third millenium B.C. The only galleried dolmen, with painted and engraved supports (and which provided the first arrowheads to be found in this group of monuments), possibly dates from the third millenium B.C. and perhaps from the second quarter. For the period of approximately 3500 to 2500 B.C., contrary to architectonic polymorphism, it appears highly likely that there was an evolution in the direction of greater complexity, size and monumentality.
We do not know much of the use of this area during the second half of the third millenium B.C. Even given the weakness of the available elements, it might be surmised that a group of monuments which were significant in number, type V, with technical characteristics, size and location which clearly indicate earlier dolmenic constructions, would correspond to be a date or dates within this period, or even perhaps from the beginning of the second millenium B.C. The "cairn" type of constructions date from the Early Bronze Age, although one of these monuments, without an internal structure, could have been built at a later period; perhaps during the second half of the second millenium B.C.
Finally, reference can be made to the graves without tumulus, which date from the latter part of the millenium and which are connected with the initial occupation of the nearest settlement. Other pre-historic remains in the region have been mentioned, namely those relating to the later population of Serra da Aboboreira.
The last chapter of the text is an attemp at a global interpretation of the pre-historic settlement of Serra da Aboboreira. The emphasis, as far as megalithic monuments are concerned, is upon aspects which have symbolic character, and which are closely related to social and economic change.

www.ci.uc.pt/iauc/pub/ac.html (in portuguese)

D. J. Cruz
Subjects: Excavations (Archaeology), Copper/ Bronze Age, Burial chamber, barrow, Megalithic monuments, Antiquities
Places: Baião (Porto), Baião (Porto, Portugal), Mamoa 1 de Chã de Carvalhal Site (Portugal), Portugal