North Walsham, Norfolk: Report on Ground Penetrating Radar Survey, December 2021
Author(s): Nicola Fairs
Phase Site Investigations Ltd was commissioned to carry out a ground penetrating radar (GPR) survey at several locations across the town centre of North Walsham, Norfolk as part of the High Street Heritage Action Zone and the ongoing Historic England Historic Area Assessment of the town centre. The objective of the survey is to attempt to locate significant anomalies related to any surviving archaeology or historic intervention. Five survey locations were specified around the Market Place and Paston College, North Walsham. Visual analysis of the GPR profiles indicates that the effective average depth penetration of the GPR data for the majority of the survey areas was generally up to 2 m. Features located at depths greater than this are unlikely to have been identified by the GPR survey. It should be noted, however, that the majority of the GPR data was relatively ‘noisy’ with a disturbed and variable background, particularly in the upper 0.5 m. So, whilst penetration was generally quite good the ‘noise’ could mask responses from some features and so not all sub-features, even those of reasonable size and contrast to the surrounding material, will have been identified.Despite the ‘noisy’ data a variety of GPR anomalies have been identified across the survey areas. Anomalies indicative of basements have been identified and additional anomalies that could also be related to parts of basements are also present. In some instances, the interpretation of the cause of some anomalies was not clear and the full extents of the underlying feature may not have been determined.
- Report Number:
- 37/2022
- Series:
- Research Report
- Pages:
- 16
- Keywords:
- Geophysical Survey Ground Penetrating Radar