2013 Marine Geophysics Data Acquisition, Processing and Interpretation Guidance Notes 1 Contents List of acronyms ................................................................3 7 Processing and analysis of geophysical data ...............32 7.1 General data processing, presentation Preface ................................................................................4 and interpretation ......................................................32 7.1.1 General geophysical data processing ..........................32 Part I Standards for geophysical survey .....................4 7.1.2 General geophysical data presentation .......................33 7.1.3 General geophysical data interpretation .....................33 1 Legislation, existing standards and guidance ...............4 7.2 Side scan sonar processing, presentation and interpretation ......................................................34 2 Geophysics and maritime archaeology .........................6 7.2.1 General side scan sonar processing, presentation and interpretation ......................................................34 3 General guidance .........................................................6 7.2.2 Side scan sonar processing, presentation 3.1 Justification for a geophysical survey ...........................6 and interpretation for wreck sites ...............................35 3.2 Fieldwork .....................................................................7 7.2.3 Side scan sonar processing, presentation 3.3 General equipment statement ......................................8 and interpretation for submerged landscapes .............36 3.3.1 Navigation ....................................................................8 7.3 Bathymetry processing, presentation 3.3.2 Side scan survey ...........................................................8 and interpretation ......................................................36 3.3.3 Bathymetric survey .......................................................8 7.3.1 General bathymetry processing, presentation 3.3.4 Sub-bottom profiler survey ...........................................8 and interpretation ......................................................36 3.3.5 Magnetometer survey ...................................................8 7.3.2 Bathymetry processing, presentation and interpretation for wreck sites ...............................37 3.4 Data treatment .............................................................8 7.3.3 Bathymetry processing, presentation 3.5 Data interpretation .......................................................8 and interpretation for submerged landscapes .............38 3.6 The survey report .........................................................8 7.4 Sub-bottom profiler processing, presentation 3.7 Data archiving and dissemination ................................9 and interpretation ......................................................39 7.4.1 General sub-bottom profiler processing, Part II Planning and reporting for a marine presentation and interpretation ..................................39 archaeo-geophysical survey ...........................................9 7.4.2 Sub-bottom profiler processing, presentation and interpretation for wreck sites ...............................40 4 Archaeology and planning ............................................9 7.4.3 Sub-bottom profiler processing, presentation and interpretation for submerged landscapes .............40 5 MoRPHE – a project’s life cycle ....................................9 7.5 Magnetometer processing, presentation 5.1 Start-up and project proposal .......................................9 and interpretation ......................................................41 5.2 Initiation and project design .........................................9 5.3 Execution stages .........................................................10 References and further reading ..................................42 5.3.1 Desk-based assessment ...............................................10 5.3.2 Fieldwork ...................................................................10 Contacts and useful addresses ....................................47 5.3.3 Data processing and analysis ......................................11 5.3.4 Assessment of data potential for further analysis .......11 5.3.5 The survey report .......................................................11 5.3.6 The main project report ..............................................11 5.3.7 End of project report ..................................................11 5.3.8 Final (digital) archiving and dissemination ................11 Part III Practitioner’s guide – techniques and geophysical instrumentation ..............................12 6 Application of techniques ...........................................12 6.1 Navigation, positioning and datum ............................12 6.1.1 Navigation and positioning ........................................12 6.1.2 Datum, coordinate system and projections .................14 6.2 Side scan sonar survey ...............................................15 6.2.1 Instrumentation – side scan sonar ..............................15 6.2.2 Survey design – side scan sonar .................................17 6.3 Bathymetry survey ......................................................19 6.3.1 Instrumentation – bathymetry ....................................19 6.3.2 Survey design – bathymetry .......................................20 6.4 Sub-bottom profiler survey .........................................23 6.4.1 Instrumentation – sub-bottom profiler .......................23 6.4.2 Survey design – sub-bottom profiler ...........................25 6.5 Magnetometer survey .................................................26 6.5.1 Instrumentation – magnetometer ...............................26 6.5.2 Survey design – magnetometer ..................................28 6.6 Integrated surveys ......................................................29 6.7 Other systems .............................................................30 2 List of acronyms ADS JNAPC UNESCO Archaeology Data Service Joint Nautical Archaeology Policy United Nations Educational, Scientific and ALSF Committee Cultural Organization Aggregate Levy Sustainability Fund JNCC UKHO BGS Joint Nature Conservation Committee UK Hydrographic Office British Geological Survey LBL UKOOA BMAPA Long Baseline United Kingdom Offshore Operators British Marine Aggregate Producers LINZ Association Association Land Information New Zealand USBL BODC MAG Ultra-short Baseline British Oceanographic Data Centre Maritime Affairs Group USGS CEFAS MBARI United States Geological Survey Centre for Environment, Fisheries and Monterey Bay Aquarium Research Institute US MMS Aquaculture Science MCA United States Minerals Management COWRIE Maritime and Coastguard Agency Service Collaborative Offshore Wind Research Into MEDIN UTM the Environment Marine Environmental Data Information Universal Transverse Mercator DBA Network VENUS Desk-based Assessment MESH Virtual Exploration of Underwater Sites DCLG Mapping European Seabed Habitats VORF Department for Communities and Local MEPF Vertical Offshore Reference Frame Government Marine Environment Protection Fund WGS84 DCMS MMO World Geodetic System 1984 Department for Culture Media and Sport Marine Management Organisation Defra MoRPHE Department for Environment, Food and Management of Research Projects in the Rural Affairs Historic Environment DGPS ms Differential Global Positioning System milliseconds DNH nT Department of National Heritage nanotesla DoE NIEA Department of the Environment Northern Ireland Environment Agency EH NOAA English Heritage National Oceanic and Atmospheric EIA Administration Environmental Impact Assessment OASIS ETRS89 Online AccesS to the Index of archaeological European Terrestrial Reference System investigationS 1989 PPK GEBCO Post-Processed Kinematic General Bathymetric Chart of the Oceans RCAHMS GPS Royal Commission on the Ancient and Global Positioning System Historic Monuments of Scotland GRS80 RCAHMW Geodetic Reference System 1980 Royal Commission on the Ancient and HER Historic Monuments of Wales Historic Environment Record REC HWTMA Regional Environmental Characterisation Hampshire and Wight Trust for Maritime ROV Archaeology Remotely Operated Vehicles Hz/kHz RTK hertz/kilohertz Real Time Kinematic ICOMOS SAR International Council on Monuments and Synthetic Aperture Radar Sites SAS IHO/IHB Synthetic Aperture Sonar International Hydrographic Organisation/ SBL Bureau Short Baseline IfA TWTT Institute for Archaeologists Two-way Travel Time 3 Preface We have tried to make these guidelines On a European scale, the UK govern- both practical and informative and able ment has ratified the European Convention These guidelines are part of the ALSF’s dis- to be used alongside other guidelines and on the Protection of the Archaeological semination of heritage information, which standards without major conflicts. It is Heritage (European Commission 1992) is managed by English Heritage. Previously impossible to produce fixed standards that and has signed the Charter on the the ALSF has funded studies of the potential can be used in all circumstances. Therefore, Protection and Management of Underwater and applicability of geophysical techniques the surveyor and researcher should have Cultural Heritage (ICOMOS 1996). Both for maritime archaeology, to provide basic some freedom to apply his or her own documents encourage the use of non- information for and characterisation