Profile B

License: 
Creative Commons Licence
Chrono starts: 
200
Chrono ends: 
400
Chronostratigraphic sequence: 

The archaeological sequence is composed by finely stratified Late Roman deposits, which originated when the building lost the bath function, and were sealed between two pavements of opus signinum, one dated in Claudian times, when the thermae were built, and a second one dated in Late Antiquity, at the end of the IV century AD and begginings of the V.

Profile: 

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Site formation processes: 

From top to bottom of the sequence:

  • 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
Archaeological significance: 

A 20 cm microstratigraphic sequence between the original opus signinum pavement (Claudian age), which contemporaneous with the thermae construction, and a later one, in Late Antiquity, informs about transformation processes that this public building underwent through time once the building was not in use for bathing.

These deposits are dominated by well sorted subangular quartz silt (<60µm) and sporadic muscovite with a high degree of alteration. The coarse fraction is moderately sorted and very homogeneous. No anthropogenic features are present, and mineralogically this sediment corresponds to the environment of the granitic hill of Munigua. Genetically, it is interpreted as a result of short-distance aeolian transport by traction and saltation (Layers 4 and 5). This process is promoted by the topographic position of the thermal complex, terraced in the hill. Only the intentional removal of tegulae roof tiles, not evidenced during excavation, can explain the presence of these aeolian deposits inside the public building. This speaks not only about the abandonment of a public building in a city that was still habited, but to the intentional and progressive dismantling of public architecture.

The later reuse of this building is mostly evinced in the microarchaeological record. The horizontal alternation of metallurgical by-products generates different microfacies unigts (Layer 3). Burned daub is associated with ashes, charcoal, as well as lead and iron slags. CaCO3 content and XRF indicate combustion events in this horizon, with Pb and Fe enrichments. It is noteworthy that a fragment of lead pipe with cut marks was documented during excavation. Dismantling processes did not only affect buildings and their construction materials, but probably other city ornaments and infrastructures too as the lead pipe fragment evinces. A process of metal recycling inside the thermae is noted both in the macro and microarchaeological scale.

This context is sealed by an opus signinum pavement (Layer 1) and its preparation layers (Layer 2). Dismantling of the public thermae is again documented during the construction process of this pavement. In fact, microfabrics of preparation layers are mainly composed of lime-based painted wall plasters (intonaci), which display a layered structure. They show a crystallitic b-fabric and different mineralogical arrangement, with coarser material in the internal one and pure lime in the exterior ones that finish in a layer of paint. BL light show that yellow and whitish pigments were used in the decorative scheme of this room. Granite minerals, such as quartz, plagioclase and biotite confirm again the use of the resources nearby to Munigua and to the granite hill as a quarry of raw material, in this case for coarse material for plasters. It must be considered that this systematic removal of wall paintings took place after the metal recycling activities, which means that during this secondary use of the building, the paintings were still in situ, and the memory of the ancient public thermae was still present. The signinum layer itself is composed of a pure lime matrix with crystallitic b-fabric with a coarse fraction of gravel-size fragments of bricks, potteries and rock. The groundmass shows layering and planar voids parallel to the surface, which formed during the drying and compaction process. Among tempers, we noted the presence of globigerina fossiliferous sandstone, which implies the quarrying of Tortonian materials. The nearest source of this raw material is the deposits located in Guadalquivir terrace deposits 5-10 km away from the city