dbSEABED Global Seabed Google Earth Browser

(Version 0.6 release, March 2022)


Download then open: dbS_global.kml
Startup image


This page delivers a compilation of information on the materials that make the world's seafloors - the rocks, sediments, biological remains.
The newest release, in April 2021, is the fifth public issue of the project.

The data show the integrated results from decades of seafloor sampling by scientists, engineers, surveyors, fishermen, divers and others.
It is based on the dbSEABED database of over 6 million described sites in 9,700 datasets, worldwide. Only the surficial seabed materials are shown here - they of greatest interest for habitats and ecology, and surveys and managament.

Users can browse values of seabed grainsize, strength, colour, composition, and also on small-scale features which are present. Images from the displays may be used in papers, reports, school projects,or for general interest.

dbSEABED uses a variety of computing and math methods to efficiently and reliably integrate the diverse data: basic database operations, fuzzy set theory (FST), geographic information systems (GIS), geostatistics.

The pointwise results here are a low-resolution  display of dbSEABED data, restricted to a small number of variables, and  involve no interpolation. The results are given as basic statistics on the seabed materials in bins of the size of a 0.1 degree (latitude/longitude) bin at the equator. The bins therefore maintain size - and therefore visibility - to the poles.  If finer data, interpolated maps or point data are needed, please contact the project office.

Back to dbSEABED Main page.
To access the coverage
  • Alternatives like GoogleMaps, Cesium or ESRI ArcEarth may display the project at top-level but unfortunately do not have full functionality required - like region-fading and networklinks.
  • The computer needs to be online for effective use of the display (network links)

Figure 2: The Bering Sea, Chukchi Sea and Gulf of Alaska seabeds are dominated by sand (yellow) and muds (green) with scattered cells with dominant gravel (red) or rock (purple). Blank areas have yet to be sampled. Grey cells have data on parameters such as carbonate content, but not on texture. The next step is to click on  and query individal cells.		Expanded image NZ


How to Use The Display

GENERAL VIEW

From the startup view (Figure 1, with banner image), zoom in to a region. When close enough (at about 8000km altitude) the cells become queriable. Then click on any cell to query for the seafloor properties which have been observed there.

Figure 3: Mapping of bottom types in the region of the Amazon Delta, showing the results of a query in a KML balloon. The mud-delta is marked in green and does not extend to the outer shelf. Instead sands and gravels (yellows, reds), many of biogenic origin, dominate in that region.Amazon Delta data and how to query



COLOR DISPLAY

The points' colours use a classification by dominant textural class: rock, gravel, sand or mud. These classes divide the seafloor at a 'top level' into hard / soft, and also into granular / cohesive, and immobile / mobile types that have great significance for seabed behaviour under stresses, erosion, and biological colonization. The classification has been popular for marine area managers because it indicates what texture type will likely be first and repeatedly encountered by sampling operations and also organisms at each location.

The DOMNT classes are defined by: first (i) rock > 66% or >50%; then (ii) which of gravel, sand, mud is dominant and >66% (superdominant), or dominant and >50%, or dominant, and >33% (i.e. subdominant). Written codes corresponding with superdominant, dominant, subdominant are of the form: GVL, Gvl, (gvl), etc. The colors are pure for dominant cases and greyish for subdominant cases. In dbSEABED purple, red, gold, green are consistently used for rock, gravel, sand and mud.

Bins where a DOMNT code cannot be computed on the existing information (but which have information on other properties like organic carbon content) but have been sampled and are queryable, are shown in gray.


Figure 4: Schematicof the Dominants2019 classification of seafloor substrates which is based on the dominant (most abundant) textural component.The Dominant Textures Classification



THE DATA-POPUPS

Each popup balloon contains summary information about the seabed which has been observed within the bin. Here are the explanations.

Sample query result

Figure 5: Example query result shown in a KML balloon.
BIN: x,y are the counts of 1/10th degree cells on the globe from -180dg meridian and -90dg (south pole) ; q is the count of equatorial 1/10th degree cells around from the -180dg meridian.

Lat,Lon: Midpoint latitude/longitude of the bin (WGS84 system)

Water depths: Median (Max..Min) in metres
Max..Min values are not shown if the same as the median value.

Samples: The number of observations and samples

Methods: Types of samplers / imagers / observations / probes

DataSources: Internal dbSEABED database "collection:index" keys.
The detailed information will be provided on request.

Parameters: Coded: Parameter|number per treatment/type; repeated.
{E=Extracted analysis or P=Parsed description} )
Note: Counts for Calculated/estimation results {C} are not shown.

DominantBottomType: Dominants2019 class for sediment texture; single result.
Syntax: [super-dominant XXX, dominant Xxx, subdominant (xxx)]; Example: "Snd=sand is dominant". Specific percentage thresholds apply.
FolkCodes: Folk codes for sediment texture; repeated.
Syntax: [(slightly x) y-ly Z]; Example: "(s)mG=slightly sandy, mudy, gravel". Specific percentage thresholds apply. The EMOD-BGS Folk classification is used.

Rock | Gravel|Sand|Mud: RockExposure % |  GravelContent | SandContent | MudContent %
(Max..Min | Max..Min|Max..Min|Max..Min %)
The GSM texture classes are by Wentworth Scale; note that due to CoDA effects, the statics on G:S:M may not total 100%, even though point and grid dbSEABED data do have CoDA closure - see HERE.

Carbt|OrgCarbn: Median (Max..Min) % | Median (Max..Min) %

Colours: Munsell Colour Codes (HueValue/Chroma; repeated)

Compnts/Featrs: Component or feature|Median (Max..Min) %; repeated. 


ABBREVIATIONS AND CODES

Parameters:  gvl - Gravel [%]; snd - Sand [%]; mud - Mud (Silt+Clay) [%]; cly - Clay [%];
                    grz - Mean Grainsize [Phi]; srt - Grainsize Sorting [Phi];
                    fac - Facies [namecode];  facmshp - Facies Membership [/1];
                    flk - Folk Sediment Texture Code [code];
                    rck - Rock Exposure [%]; veg - Soft Vegetation Cover (e.g., soft algae and seagrass) [%];
                    crb - Carbonate Content [%]; mun - Munsell Colour Code [code]; ocbn - Organic Carbon [%];
                    shrstr - Shear Stress [kPa]; por - Porosity [%]; pwvel - P-Wave Sound Velocity [km/s];
                    rghns - Bottom Roughness [V:H log2(mm)]; cshrstrs - Critical Shear Stress [kPa];
                    geoage - Geological Age of Formation [young limit Ma:old limit Ma]

Components: calct - Calcite; dolmt - Dolomite; qtz - Quartz;
            kaol - Kaolinite (Analysed); smect - Smectite (Analysed);
            pyrt - Pyrite; hvy_min - Heavy Minerals; glauc - 'Glauconite'; 
            mica - Micas; fld - Feldspars; phspht - Phosphate; hydrt - Hydrotroilite;
            silca - Silica (Amorphous); gyps - Gypsum; zeol - Zeolites; sulfd - Sulphides; 
            coralgl - Coral & Calcareous Algal; crl - Hard Coral (whole);
            crl_dbr - Coral Debris; sol_crl - Solitary Hard Corals; ostr - Ostracods;
            octcor - Octocoral Remains; brncl - Barnacle Remains; 
            mlsc - Mollusc (incl. 'clams', gastropods, scaphopods, etc); biv - Bivalve;
            oyst - Oyster; musl - Mussels; shl - Shell (unbroken); shl_dbr - Shell Debris;
            rzr_clm - Razor Clams; scllp - Scallops; gstrpd - Gastropod;
            bryz - Bryozoan; brach - Brachiopod; srpul - Serpulid; crustcn - Crustacean;
            crinod - Crinoid; ophiurd - Ophiuroid (Brittle Star); echnoid - Echinoid (Sea Urchin);
            snd_dollr - Sand Dollar (Clypasteroid); c_alg - Calcareous Algal; rhodl - Rhodolith; halmda - Halimeda;
            nan - Nannofossil (Coccolith); ptr - Pteropod; rad - Radiolarian; diat - Diatom;
            frm - Foraminifera (Foram); plnk_frm - Planktic Foram; bnth_frm - Benthic Foram;
            lrg_frm - Large Forams (benthic, e.g. Marginopora); coal - Coal and Peat; 
            wood - Wood; oolt - Oolite; volgls - Volcanic Glass; baslt - Basalt; chrt - Chert;
            gbbro - Gabbro; umafic - Ultramafic Rock; volc - Volcanic and Volcanoclastic; \
            fe_nod - Iron (Oxide, Hydroxide) Nodules; metlif - Metalliferous; pumc - Pumice;
            calc_nod - Calcareous Nodules; clst - Clasts; mn_nod - Manganese Nodules.

Features: gas_F - Gas, Gas Bubble, Gas Escape Features;
            odr_F - Odours; h2s_F - Hydrogen Sulphide Odour;
            weed_F - Weed (Algae & Seagrass); seagrs_F - Seagrass;
            void_F - Voids; 
            ripl_F - Ripples, Megaripples; erosn_F - Erosion (Flute, Crag & Tail) Features;
            fces_F - Faeces, Fecal Pellets; burw_F - Burrowing;
            hydrthrml_vnt_F - Hydrothermal vents & Venting; 
            hrdgrond_F - Hardgrounds, Crusts.

Note:
Whereas components have abundances which should sum to 100%, features (marked with an '_F')
      have intensities of development which are not constrained that way.
Some of the above component classes overlap (e.g. 'shell' and 'bivalve'), so total abundances not sum to 100%.

MORE INFORMATION

Some statistics for the coverage in April 2021:
   
    Number of described sites: 3,965,605
             observations:   5,921,628
             contributing datasets:  11,248
             data values: 118,432,560

    Number of cores into subbottom (>10cm penetration): 210,934
    
    Number of  0.1dg cells having data:    155,912 (16,797 have no data on texture, are colored grey)
   
    Percent of 0.1dg ocean cells sampled:    3.6% of the total 4,431,461 ocean 0.1dg cells
   
    Median distance to nearest cell with data at 0.1dg scale:
            any ocean cell :    75km
            any ocean cell in ~photic zone (0-50m WD): 22km
            any ocean cell of continental shelves (0-200m WD): 24km

Note: Although it is commonly used in papers, the statistic "average minimum distance between cells with data" lacks meaning
and can be very misleading. For instance if there is an intense survey of one area within a larger map area. Most of the map
may not have any data. Therefore instead, we use median distance to data from all marine cells in a map area.


Helpful pages on the dbSEABED website:
     Specification of Output Formats
     dbSEABED Helpful pages.

From Floor of the Ocean LLC,
delivered by CU Boulder, March 2022