Bisenzio. Multi-disciplinary research of an important Etruscan centre from the Late Bronze Age to the Archaic Period
In the archaeological research project at Monte Bisenzio (Italy), the i3mainz is responsible for the metrological basics and the sustainable administration of the research data. The project, which is funded by the DFG for an initial period of three years, focuses on archaeological-geophysical prospection, systematic inspection and the processing of old finds from a centre of the early Tuscan culture. The aim of the project is to gain a better understanding of Bisenzio in a broader context - both in relation to other important centres in southern Etruria and more generally in the context of urbanisation processes and social developments in the wider Mediterranean region. Prof. Dr. Christopher Pare (JGU) and Dr. Andrea Babbi (RGZM) are responsible for the project. The geophysical measurements are carried out by LBI ArchPro (Vienna).
The work of the i3mainz within the international cooperation project “Bisenzio. Multi-disciplinary research of an important Etruscan centre from the Late Bronze Age to the Archaic Period” focus on ensuring a sufficiently accurate geodetic reference frame for the prospecting work of the cooperation partners and the consolidation and sustainable provision of the research data obtained.
Bisenzio is located on the western shore of Lake Bolsena in the Volsin Mountains north of Rome. The hilltop of Monte Bisenzio, which is connected to the adjacent hills to the west by a ridge of high ground, pushes into the lake. River courses have cut through the tufa rock and wide alluvial fans have been heaped up to the north and south of Monte Bisenzio. They form the area of the Roman city of Visentium and the Etruscan settlement abandoned around 500 BC, whose ancient name has not been handed down.
The first traces of settlement on Monte Bisenzio date back to the 10th century BC and thus to the Bronze Age. Among experts, however, the Etruscan Bisenzio is mainly known because of numerous grave finds from the necropolises of Olmo Bello, Polledrara or San Bernardino in the vicinity of the settlement area.
The starting point for the activities of the i3mainz is the agricultural survey area, which covers an area of 2.5 km² and is completely geophysically prospected in the accessible areas by the LBI ArchPro. According to the geology of the survey area, different georadar systems (ground penetrating radar, GPR) are used, which record signals with a spatial resolution of approx. 8x8 cm and provide information about the reflection behaviour of surfaces in the subsurface. This mapping of ground encroachment by humans is evaluated in combination with the results of the field survey, during which superficially exposed features and objects are documented tachymetrically. The measurement network must therefore ensure the necessary accuracy of the positional determinations of both methods in the 2.5 km² area, so that the results of the fieldwalking and the GPR measurements can be reliably located in relation to each other.
They form the basis for the evaluation of the chronological development and the internal spatial and functional division of the Etruscan settlement on Monte Bisenzio.
Margaritha Vogt and Kai-Christian Bruhn carried out the surveying work in the first campaign of the project from 5 July to 17 July 2015. A total of 76 points were re-marketed and surveyed in the study area. An additional 7 measurements supported the geophysical survey work and the location of geological boreholes in the study area was surveyed for colleagues from ISPRA in Naples.
The position of the points is determined in four superior coordinate systems (WGS84, ETRS2000 UTM32N, ETRS2000 UTM33N and ECEF). The transformation parameters, especially from WGS84 coordinates to an old system of the Italian national survey (Gauss-Boaga), were determined on site.
A local coordinate system was determined for the archaeological survey work (KaMa-Bisenzio). The heights in the KaMa-Bisenzio grid are geometric heights that refer to the geoid model EGG97.
In the run-up to the work on site, Tobias Kohr, Thomas Engel and Axel Kunz collected geodata from the study area and prepared data sets for the research work that were made available by Italian geodata agencies through Andrea Babbi. They are available to all project partners via a web-based GIS, which is realised with the GeoExplorer framework and also serves the exchange of data between the cooperation partners during the course of the project.
The results of the activities in the first project year are the WebGIS application, which represents all existing information in its spatial reference and is successively supplemented by the project partners. In addition, a summary report, a detailed point documentation and the archived survey data form the basis for the survey work and field visits.