The document describes the NuraghEO project which uses aerial and satellite data to study Sardinian Nuragic archaeological sites. The project aims to develop a methodology using remote sensing to identify areas of interest for excavation and monitor sites for subsidence or other changes. Researchers are analyzing interferometric radar data to detect ground motions and optical data to map vegetation and temperature anomalies that could indicate buried structures. The Planetek Rheticus Platform is providing multi-temporal aerial and satellite imagery which is analyzed using algorithms to identify areas needing further study and monitoring to help archaeological research.

1. NuraghEO, a methodology based on aerial and
satellite data for the preliminary study of
Sardinian Nuragic sites
Roberto Demontis, CRS4

2. CENTER FOR ADVANCED STUDIES, RESEARCH AND
DEVELOPMENT IN SARDINIA (ITALY)
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3. Introduction
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Sardinia island has an enormous
cultural and identity heritage from
the Pre-Nuragic (3200−2700 BC)
and Nuragic (up to the 2nd century
AD) periods.
It is estimated that there are about of
5000 Nuraghes, more than 550
domus de janas, 60 holy wells, 500
giants’ graves, 200 villages and 110
menhirs.
https://nurnet.crs4.it/nurnetgeo/

4. Introduction
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The excavation activities can be
difficult in terms of effort and costs:
satellite and aerial images can be
useful to assess in advance the need
of excavation activities for a specific
area.
Phenomena such as natural and
induced subsidence could prevent
access to buried structures and even
damage the emerged ones.

5. The NuraghEO Project
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6. NuraghEO - Main Objective
The main objective of the project is to define a methodology allowing a new
approach for the study of archaeological sites through the pervasive use
of remote sensing technologies. The method could be systematically applied
to other territories and it consists of:
1. the analysis of EO data to identify and document areas of interest with
possible buried structures (e.g. a village near a nuraghe)
2. the integration of the results of different detection techniques
(photogrammetry, georadar, LIDAR, thermal camera) within a well-defined
experimental set, in which to verify and increase the quality of the
produced results
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7. NuraghEO: Identity Card
● NuraghEO is connected to ArchaeoSardinia, a project funded by the Sardinia
Regional Government (RAS/CRP, LR7/2007) and focused on the "Nuraghe Nanni
Arrù", a polilobate semi-buried nuraghe near Cagliari.
● OCRE mini competition:
start date: March 2022
end date: May 2022
● Voucher amount:
75.000 Euro
● NuraghEO project:
start date: 1 June 2022
end date: 31 May 2023
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8. Study Area
Area: 315 km²
Sites of interest: 10
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9. EO Services
Thanks to OCRE’s Earth Observation voucher for Planetek Rheticus Platform, the
CRS4 researchers are able to overcome the need of managing high data volumes
and having strong data processing capacities.
Two main types of analysis:
○ Multi-Temporal Interferometric analysis (MTI) of SAR images to detect
and monitor land surface changes around archaeological sites that may be
subject to subsidence or landslides
○ Multi-Temporal/Multi-Sensor analysis with new generation optical EO
data: calculation of indices related to the vegetation state, temperature
and soil moisture
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10. Multi-Temporal Interferometric analysis
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✔ Ground motion analysis over 48 months of high resolution data!
✔ Persistent Scatters calculated with millimeter precision
• Monitoring of movements, both on the nuraghe and on the surrounding areas
• Support for identifying areas with potential buried archaeology

11. Multi-temporal/multi-sensor analysis
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Planet Fusion Monitoring:
✔ New product data-fusion between
Planet e Sentinel-2
✔ Higher frequency and higher
accuracy (3.7m)

12. Multi-temporal/multi-sensor analysis
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• Mapping of areas with
homogeneous characteristics
• Identification of anomalies that can
be potentially related to buried
archeology
• Monitoring of environmental
conditions in the study area

13. Rethicus Cloud hosted Platform
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Variable size
Cells definition
The satellite
collects the
information
The algorithms analyze
and classify the portions
of territory
Rheticus® Safeland
shows the areas to
monitor
End user
makes the
decisions
Cloud-hosted platform,
fully owned and operated by Planetek
Easy and
intuitive
Reporting

14. Rethicus Cloud hosted Platform
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Easy and
intuitive
Reporting
Optical
Radar
The satellite
collects the
information
The algorithms analyze
and classify the portions
of territory
Rheticus® Safeland
shows the areas to
monitor
End user
makes the
decisions

15. Rheticus Displacement - MTI results

16. Rheticus Displacement - MTI results

17. Multi-temporal/multi-sensor analysis
➢ Indices computed for years 2018-2022:
➢ Automatic data processing pipeline

18. Sentinel-2 NDWI- July 2018 PlanetFusion NDVI- July 2018 LST- July 2018
Multi-temporal/multi-sensor analysis
➢ Example: Nuraghe Nanni Arrù
Nuraghe Nanni Arrù

19. Multi-temporal/multi-sensor analysis
NDWI
NDMI
NAI
MSI

20. Multi-temporal/multi-sensor analysis
NDVI
MSAVI2
CVI

21. Multi-temporal/multi-sensor analysis
Multi-temporal
AI-based
clustering

22. Conclusions
The availability of the voucher to access the Planetek Rheticus Platform
allowed CRS4 to simplify the complexity and management of data.
This opportunity accelerates the path towards the achievement of the
results, avoiding the development from scratch and internally.
In short:
a valid opportunity that is worth to be considered also for
future works!
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23. Thanks