Spectroscopy and Geochemistry of chert. Reconstructing human mobility in the Pyrenees from the first Modern Humans to the last Pleistocene hunter-gatherers

Project Information

SPEGEOCHERT

Grant agreement ID: 101075451

DOI

10.3030/101075451

EC signature date 28 November 2022

Start date 1 October 2023

End date 30 September 2028

Funded under

• European Research Council (ERC)

Total cost

€ 1 500 000,00

EU contribution

€ 1 500 000,00

Coordinated by

UNIVERSITAT DE BARCELONA
Spain

Periodic Reporting for period 1 - SPEGEOCHERT (Spectroscopy and Geochemistry of chert. Reconstructing human mobility in the Pyrenees from the first Modern Humans to the last Pleistocene hunter-gatherers)

Reporting period: 2023-10-01 to 2026-03-31

Summary of the context and overall objectives of the project

During the Late Pleistocene, the Pyrenean range presented highly variable climatic conditions, alternating between glacial phases and temperate periods. Archaeological evidence demonstrates that human groups adapted to these harsh environments and occupied high-altitude areas previously considered uninhabitable, such as Montlleó (Lleida, Spain). These findings challenge traditional models that restricted trans-Pyrenean mobility to the western and eastern extremes. Geochemical analyses of lithic raw materials from Upper Palaeolithic assemblages reveal long-distance connections between northern and southern slopes, suggesting multiple crossing routes, including central sectors of the range. Similarities in symbolic expressions, such as cave art motifs, further support the hypothesis of a shared trans-Pyrenean cultural territory.
Building on these premises, the project aims to:
1. Investigate how hunter-gatherer groups adapted to the environmental constraints of a high mountain range, particularly regarding the procurement and management of lithic resources;
2. Identify mobility routes across the Pyrenees and assess whether these changed over time in response to climatic fluctuations;
3. Compare territorial strategies of the first Modern Humans with those of Late Pleistocene hunter-gatherers to understand their evolution.
By integrating archaeological, geological, and geochemical data, the project seeks to reconstruct patterns of resource exploitation and mobility, contributing to broader debates on human resilience and adaptation in extreme environments.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Over the past two years, our project has focused on understanding how human groups moved across the Pyrenees from the arrival of the first Modern Humans to the last hunter-gatherers of the Pleistocene. We aim to uncover how these communities adapted to extreme mountain environments and identify the routes they used to cross this natural barrier.
To achieve this, we are applying innovative methods to study chert, the raw material most used for stone tools. By precisely characterizing chert from archaeological sites and linking it to its geological sources, we can trace mobility patterns and resource management strategies.
In the first 24 months our work has included:
• Mapping geological sources of four key types of chert widely used during the Upper Palaeolithic. Extensive field surveys have documented outcrops across the Pyrenees, collecting thousands of samples for analysis.
• Building an open-access database that will host detailed information on these sources and analytical results, creating a valuable resource for future research.
• Developing advanced analytical techniques, including spectroscopic and geochemical methods, to classify chert samples and compare archaeological and geological materials.
• Creating predictive models using GIS and glaciation data to reconstruct possible mobility routes and understand how climate shaped human movement.
So far, more than 2,000 geological samples have been analyzed, and computational models are being developed to interpret this vast dataset. In the coming months, we will integrate archaeological data to reveal how hunter-gatherers navigated the Pyrenean landscape and adapted to changing climates—shedding light on resilience and connectivity in prehistoric Europe.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

In the first two years of the project, we achieved a major scientific milestone: applying Laser-Induced Breakdown Spectroscopy (LIBS) to the study of chert, a material widely used for prehistoric tools. This innovative technique, combined with advanced data processing, now stands alongside established methods like ED-XRF and LA-ICP-MS. It allows us to classify chert types with greater precision, opening new possibilities for tracing human mobility and resource use during the Last Glacial Period.
Another key achievement is the creation of a comprehensive project database, currently in restricted access but designed for future open use by the scientific community. Unlike existing resources, our database will not only map geological outcrops but also include detailed analytical data for each sample—covering more than 3,000 geological chert specimens and, later, archaeological artifacts. This will be the first open-access platform of its kind in Spain, marking a significant step forward in European research on prehistoric raw materials.
These advances will help us answer fundamental questions: How did hunter-gatherers adapt to extreme mountain environments? Which routes did they use to cross the Pyrenees? How did climate change shape their movements and survival strategies? By combining cutting-edge science with archaeological evidence, our project will shed light on human resilience and connectivity in prehistoric Europe—providing insights that resonate far beyond the Pyrenees.