Coastal landslide monitoring at Aldbrough, East Riding of Yorkshire, UK.

The paper describes results to date of an ongoing monitoring study of coastal ‘soft cliff’ recession at the British Geological Survey (BGS)’s ‘Coastal Landslide Observatory’ (CLO) on the east coast of England at Aldbrough, East Riding of Yorkshire, UK. The cliffed site, part of the 50 km long Holderness coast, consists of glacial deposits, and is one of the most rapidly eroding coastlines in Europe. This rapid rate of erosion provides an ideal opportunity for observation and process understanding because it facilitates the collection of data over periods of time encompassing significant new landslide events at the same location. The results of two approaches are reported: firstly terrestrial LiDAR surveying (TLS) and secondly the installation of instrumented boreholes. The aim of the research is to combine these to investigate the role of landslides and their pre-conditioning factors and the influence of geology, geotechnics, topography and environmental factors on cliff recession. To date, an average recession rate of 1.8 m per year and a maximum rate of 3.4 m per year have been recorded for the site. The establishment of the CLO and its conceptual geological / geotechnical model are described in a related article (Hobbs et al. 2019a).