14Four hundred square kilometres of one metre binned, full coverage swath bathymetry data, 15 integrated with similar resolution onshore topography, has been used to generate a seamless 16 onshore to offshore bedrock map covering an extensive area adjacent to the "Jurassic Coast" 17 World Heritage site. Analysis of these data provides new insights into the structural development 18 of the Purbeck Monocline Cenozoic inversion structure, in particular, variations in the expression 19 of strain between the hanging wall block and the fault inversion zone. The footwall to the basin-20 pdf bounding faults compartmentalized deformation and uplift, and acted as a buttress to 21 compression. The data also show a lack of significant thickness changes within the major 22 lithostratigraphical divisions, and a notable absence of basin-related extensional faulting in the 23 offshore area that is in marked contrast to the more extensively studied onshore region. This 24Sanderson et al MS Click here to download Article text Sanderson Dix Westhead Collier MS.indicates that prior to inversion, the basin evolved by intermittent activity on a few major 25 extensional faults. This improved understanding of the development of the basin and inversion 26 structures results from our ability to integrate and quantitatively manipulate these high resolution 27 and spatially extensive offshore and onshore datasets. 28

Recent advances in marine acoustic survey and land-based topographic monitoring technologies have resulted in increasingly cost-effective data acquisition in coastal areas. The DEFRA-funded National Network of Regional Coastal Monitoring Programmes of England are, for example, utilising swath bathymetry and airborne light detection and ranging (LiDAR) technology more routinely to survey the coastal zone around the coastline of England. The demand for data processing, visualisation and interpretation techniques to keep pace with such advances in data acquisition is clear. This study discusses collection and processing techniques for such data on the south coast of Dorset, England, which have enabled the production of a seamless, high spatial resolution digital elevation model across the coastal zone. Case studies demonstrate how this elevation model can be viewed and analysed using state-of-the-art digital techniques to allow geological mapping to be extended from onshore to offshore in unprecedented detail, effectively eliminating what is known as the 'White Ribbon' for coastal geological mapping. The potential for rolling out such techniques for wider surveying programmes across many environmental disciplines is significant, which could contribute towards improving the multi-disciplinary scientific evidence base in the complex coastal zone.

The demand for marine-related spatial information has become increasingly apparent in recent years at a European and national scale, due to the increased pressures on the sea-floor environments and marine resources of UK territorial waters. The advent of economically viable swath bathymetry data acquisition in the coastal zone and effective collaborative partnerships between the Channel Coastal Observatory, Maritime and Coastguard Agency, UK Hydrographic Office, British Geological Survey and academic institutions, have opened up new opportunities to produce a robust scientific evidence base to inform integrated coastal zone management objectives and contribute to wider scientific initiatives. Interpretation of high-quality bathymetric data, acoustic backscatter and ground-truthing data allows zones of exposed bedrock, rock outcrops and pinnacles to be identified, along with areas of mobility or stability of surficial sediments. Temporal and spatial analyses of coastal and marine monitoring datasets also contribute to improved understanding of interactions between natural coastal process and coastal-defence and beach-management operations. Furthermore, developments in three-dimensional mapping techniques and visualisation technologies have enabled seamless high-resolution coastal geology maps to be re-interpreted and extended offshore, providing a more complete picture of the baseline geology, physical properties, structure and geohazards in the coastal and nearshore zone. The full paper details the methodology developed to produce a range of indicative marine mapping layers, and presents examples from eastern and southern England where marine-related spatial data has contributed to the multi-disciplinary scientific evidence base to inform development of UK marine policy and planning, coastal management and coastal zone geological mapping.

No abstract