Airborne lidar intensity and geoarchaeological prospection in river valley floors

Abstract

Archaeological applications of airborne lidar topographic data are now well known and documented in the academic literature. Rather less well explored by archaeologists are the potential of lidar intensity data. In this paper we explore the application of lidar intensity for geoarchaeological prospection in river valley floors. After briefly considering the context of archaeological remote sensing in river valleys, we examine some factors influencing the lidar intensity record and explore processing steps that may be required to effectively utilize intensity data, before reviewing the utility of intensity data for the geoarchaeological assessment of test sites in the Trent Valley of the English Midlands (UK). Results suggest that intensity imagery may assist greatly in the interpretation of airborne lidar topographic data and that its analysis contributes to a qualitative understanding of land cover and the burial environment of archaeological remains, either cultural or environmental; furthermore in some circumstances it is possible to identify anthropogenic archaeological cropmarks in intensity imagery. It is concluded that the standard methodology employed in using airborne lidar for archaeological survey should as a matter of course include the collection and analysis of intensity data. © 2011 John Wiley & Sons, Ltd.