Sérézin-du-Rhône – 34 rue Claude-Brosse

1The diagnostic operation took place in the town of Sérézin-du-Rhône, 34 rue Claude-Brosse, from July 7 to 10, 2020. The plot diagnosed is located on the right-of-way of a building construction project of dwellings which led to the prescription of an archaeological diagnosis. The mechanical soundings made it possible to highlight several phases of occupations spread over the entire right-of-way. All of these archaeological remains are located on the edge of the Ozon, in an ancient complex alluvial system of the “meandering” type, the geometry of which could not be precisely determined at the end of our intervention. In addition, a paleovallon was notably unearthed not far from the western border of the diagnosis.

2The oldest period identified corresponds to the Neolithic. It could be characterized by the intermediary of a ceramic shard taken from a layer located 1.70 m deep, at a place where the stratigraphy of the site develops over more than 2.20 m in thickness without the geological substratum has not been reached. This would be one of the oldest indications of human attendance in this sector of Sérézin, or even throughout the town.

3The archaeological occupation most represented on the hold by the remains and levels unearthed is linked to Antiquity, without any evidence of a protohistoric presence or occupation having been identified. Remains, of various nature and function, have been brought to light in all the archaeological surveys carried out. They take the form of ditched structures (post holes, pits, ditches) and developed levels located between 0.75 and 1.30 m below the surface. The study of the ceramic furniture collected allows us to propose a chronological range between the Augustan period, for the first signs of occupation, and the ii^e s. apr. AD for the later elements. In addition, a layer made up of pebbles, re-used blocks and archaeological material laid flat (ancient ceramics and fauna) appeared in the filling of the paleovallon over approximately 2 m in width (survey 1 – F1), and could refer to a development. edge of bank. The ancient occupation is also characterized by a level rich in charcoal observed very locally in hole 4 at a depth of between 1.05 and 1.35 m below the surface (US 12). It yielded a large number of forging activity residues (blast furnace slag, hearth walls, scale) associated with faunal remains and ceramic shards, the strong fragmentation of which could suggest a trampling zone (or level of traffic ). The ceramological study of the shards collected in this level refers to the Augustan period (-30-0).

4The ancient remains unearthed during this operation could be located in the grip of the domain attached to the luxurious villa identified in the area of ​​the station, about 600 m further south, whose occupation spanned between the Augustan period and the middle of the iii^e s. apr. AD The Ozon could then mark a strong natural limit at the northern limit of the territory attached to this residence (some rural ?). The occupation uncovered on the right-of-way could also be linked to the ancient habitat destroyed in 1971 during the construction of the Le Hameau-de-Sérézin subdivision, 300 m east of the diagnostic right-of-way. The stylistic study of the painted plasters that had been collected then suggested a dating around the first half of the i^is s. apr. AD However, the absence of a search and the incomplete documentation about it do not make it possible to determine its nature and the functions allocated to it.

5Remains of the medieval period could be identified locally on the right-of-way. Essentially, this is a short section of a gutter (F2) unearthed in borehole 2. The excavation of its central infill yielded several shards of ancient ceramic and three shards dated from the central Middle Ages (x^e–xii^e s.) for the most recent. In addition, this gutter is covered with a thick clay layer (US 3), rich in antique furniture (mainly large fragments of tiling, imbrices and bricks), which covers the right-of-way over its entire surface and could have been brought back during the medieval period, or even later, to enhance and exploit an area subject to regular flooding of the Ozon.

6Finally, two parallel ditches cross the right-of-way from east to west. They are only covered with the current topsoil and filled with a homogeneous sediment, without visible bedding, over their entire thickness. A development made up of sandstone slabs was also unearthed in one of the trenches bordering these ditches. These could be witnesses of an old drainage or irrigation system known in the area at the start of the xx^e s.

7The signs of Neolithic frequentation and the ancient and medieval occupations identified during this diagnosis confirm the archaeological potential over the entire territory of Sérézin-du-Rhône. They bring new elements as to the ancient structure of the town bordering the Ozon, but also for the medieval occupation, which, until then, was mainly recognized south of the railway station.