Assessing natural vs anthropogenic horizons through deposit modelling strategies at the Medieval Site of Santa Margarida (Martorell, Barcelona, Spain)

Abstract

Geophysical surveys have been one of the most useful tools for non‐invasive archaeological field assessment. Whereas they have been regularly put into practice at the archaeological site of Santa Margarida (Martorell, Barcelona, Spain), the particular features of the site required a more specific strategy to identify the contact interface between anthropogenic and natural deposits and, therefore, to conclude the archaeological excavation. As the archaeological site is settled on Quaternary alluvia at the confluence of two rivers, and in the absence of built structures in some areas, it was extremely difficult to distinguish between anthropic layers and those silty or sandy natural deposits during fieldwork. Extensive soil survey by means of borehole logging, full‐coring, and Dynamic Penetrometer Super Heavy testing within this site has proved to be a useful strategy to identify the geological horizon and to map the original relief of past landscape before excavation tasks. This enabled us to plan our fieldwork better and to interpret particular features of the site. This paper aims at summarising the results of recent surveys and discussing the potential of this approach for the study of rural settlements and agrarian landscapes in the Middle Age.