Learn more about the science conducted by the ICONOPASTT team members
After six thousand years of Holocene history where marine predation of territories was slow, the 21st century marks a radical change in the rates of modification of coastal landscapes.
The natural formations and fossilized markers of human activity are witnesses and analogues that allow us to better understand the resilience of these environments and human occupations. Past flooding/submergence zones are zones of preferential fragility, thus presenting the highest probability of reactivation in the context of a rapid rise in sea level, in contrast to zones where habitats have remained stable over the millennia.
During these periods of strong variations in the natural environment, coastal communities were able to adjust and even adapt despite their vulnerability by demonstrating a certain flexibility in the occupation and exploitation of a mobile territory (change of subsistence economy, withdrawal, developments...). However, this memory is lost within one or two centuries and exists only in the archaeological archives, which are still incompletely recorded and studied on the coast, even though they are disappearing as the sea level rises.
This project aims to collect observations from the collective memory through the banking of private iconographic documents (photos, postcards, ...). It is part of the dynamics of several projects launched in 2013, the LITAQ projects (INTERLABEX COTE/LASCARBX: From the Pleistocene to the Anthropocene: knowing the past mechanisms of evolution of populations -plant, animal, human- and environments to predict future responses. L'exemple du LITtoral AQuitain, 2013-2015, http://litaq.huma-num.fr) and EC2CO DRIL FAST-LITAQ (Formations Argilo-Sableuses & Tourbes LITtorales AQuitaines: de leur intérêt dans l'évolution des falaises dunaires du Médoc, 2016-2017, http://www.geocean.net/wikilitaq/doku.php). These two projects were linked by combining the multidisciplinary skills of archaeologists, geographers and geologists in order to better understand the dynamics of human/environmental/climate evolution of the northern Médoc coastlines on a prehistoric and historical scale. They are now relayed by the New Aquitaine ESTRAN project (Erosion and Society in the Long Term on the Shores of New Aquitaine) which involves a very broad non-academic community (Communauté de Communes Médoc-Atlantique- CDCMA, Département des Recherches Archéologiques Subaquatiques et Sous-Marines-DRASSM, Bordeaux Métropole, Service Archéologique Départemental de Charente-Maritime, Service Régional de l'Archéologie Nouvelle-Aquitaine, Service du Patrimoine et de l'Inventaire - Site de Bordeaux, Archives Départementales de la Gironde, Archives du Port Maritime de Bordeaux, BRGM Direction Nouvelle-Aquitaine).
Our work aims at reconstructing the evolution of coastal territories and habitats in the past in order to identify critical areas in a context of accelerated sea level rise. Thanks to the scientific advances obtained since 2013, the discussions held with all the partners, and the exchanges with the walkers during our excavations on the beach, it appeared obvious that our observations could be enriched by an effective participation of the local or passing population, notably through the collection of iconographic documents. Many witnesses spontaneously report their memories of events and discoveries on the beach that they have sometimes photographed. This project relies on the growing interest that the inhabitants have for their territory, which has been weakened by the major environmental transition that characterizes the 21st century.
We hope to collect unpublished documents and thus create an observatory of the memory of the changes that have marked the last 120 years, and thus ensure the banking and perpetuation.
One of the concrete objectives of this project is to constitute an illustrated retrospective calendar filling the gaps in scientific observations because our field missions remain punctual, we know to miss important events because the variability of the state of the beaches is great with a moving sand cover from one tide to another on the formations. Another problematic aspect is
related to the works carried out on the beach which, to recharge these last ones in sand, can also alter the studied formations.
The latest report of the IPCC Aquitaine highlights the dimension of loss of "memory" suffered by our modern societies for half a century as a factor of aggravation of risks (Garnier et al., 2017). If this societal oblivion is difficult to circumvent (over-focus on current issues), a "memory" remains in the recent geological archives of the coasts, such as those of the Soulac/mer sector. The submergence of ancient societies during the rise in sea level over the last ten millennia has indeed trapped traces of anthropic activities throughout the maritime territory. These submerged vestiges or in the process of being submerged constitute exceptional witnesses of the resilience of territories and societies.
From this geological or archaeological memory, which is not very readable for non-specialists, we wish to move towards a citizen memory, accessible to all and built by all.