Samples and associated geological data are held at the British Geological Survey for Maritime Coastguard Agency (MCA), Civil Hydrography Programme (CHP), Bathymetric Survey HI1447; Blakeney Overfalls, Area in SqKm: 93, (26/01/2014 to 20/02/2014), Standard: IHO S44ed5 Order 1a. Contract: Medium. FY 2013/14. Contractor: MMT UK.