Profile A1

Chrono starts: 
-100
Chrono ends: 
50
Chronostratigraphic sequence: 

The sequence begins with the presence of a negative stratigraphic unit resulting from the carving of granite to create a combustion structure (SU 0). The presence of this metallurgical furnace creates a clear division of the stratigraphy, conditioned by what happens in the interior and the exterior of the combustion structure. SU 1 shows a sandy texture, high porosity and sand size granulometry, composed by weathered granite with signs of thermal alteration. On it is located the SU 2, which shows sandy texture, yellowish color, medium porosity and granulometry of sand size. It follows the SU 3, horizontally arranged on UE 2 and composed mainly by gravel size charcoals and ashes. It presents macroscopic remains of lead slags and occasionally angular fragments of granite.

Inside the structure a series of stratigraphic units related to the last combustion event of the metallurgical furnace have been identified. On the one hand, the SU 4 consists mainly of fragments of iron oxides and slags. These fragments serve as a matrix to a quartz and mica sand. By sealing this unit, the SU 5 is composed exclusively of burned daub fragments corresponding to the walls of the furnace. They show the signs of the thermal alteration.

On units 3 and 5 is the SU 6, with 25 cm maximum high, brown color, clay texture and low porosity. It presents inclusions of angular fragments of granite, brick and burned daub. In addition, there are rounded fragments of mortar. In some places there is the horizontal trend of clasts and aggregates which, macroscopically, are difficult to distinguish as differentiated from SU's. This unit is covered by four different units: SU 7, which is composed by burned daub fragments; SU 8, a few millimeters thick blackish layer composed of ash and charcoal; The SU 8, which is a dark-brown lens; And SU 9, a layer of grayish-brown, silty texture and low porosity. It presents some charcoals horizontally arranged and few inclusions of burned daub. This SU is covered by SU 10 and 13, which has been considered stratigraphically equal. These are composed by iron slags which serves as the matrix to a quartz and mica sand. Up to them, two sterile units have been identified: SU's 12 and 11. The first is a yellowish brown unit with silty texture and no porosity. The second one is very similar, with a variation in color towards grayish brown. These units are covered by SU 14, a quartz and mica sand resulting from the breakdown of granite, as well as by the SU 15, composed mainly of sub-rounded mortar. Both units and SU 16 as well, act the preparation layer for an opus signinum pavement (SU 17).

Profile: 

 12

Site formation processes: 
  • Opus signinum pavement construction
  • Preparation layers composed by lime-based painted wall plasters fragments
  • Metal recycling activities
  • Short-distance aeolian transport (traction and saltation processes)
  • Opus signinum pavement construction