dbSEABED Google Earth Browser

(Version 0.2 release, June 2018)



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 June 2018, is version 2 of the project.

The site shows 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, worldwide. Only the surficial seabed materials are shown here - since 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: fuzzy set theory (FST), geographic information systems (GIS), geostatistics, machine learning (ML), and natural language processing (NLP).

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 each 0.1 degree (latitude/longitude) bin.  If 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.

Figure to the right: southern New Zealand shallow seabed is dominated by exposed rock (purple) under the influence of Southern Ocean wave climate and the uplift tectonics. Sand (yellow) dominates the shelves otherwise, with some small patches of muds (green) and scattered cells with gravel (red) dominant. Blank areas have yet to be sampled. Each cell can be queried for a summary of the data and the seafloor there.
Expanded image



How to Use The Display

GENERAL VIEW


From the startup view, zoom in to a region. When close enough (at about 1000km altitude) the cells become queriable. Then click on any cell to find out the seafloor properties that have been observed there.

General view of the Kml page



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 to soft and solid / granular / cohesive, and immobile / mobile areas that have great significance for behaviour under stress, erosion and biological colonization.

The DOMNC classes are defined by (i) rock > 66% or rock>50%, then (ii) which of gravel, sand, mud is dominant and >66%, or dominant and >33% (i.e. subdominant). The colors are pure for dominant cases and greyish for subdominant cases. In dbSEABED purple, red, yellow, green are consistently used for rock, gravel, sand and mud.


The Dominant Textures Classification

Cells with an outline but no color have been sampled and are queryable, but a DOMNC code cannot be computed on the existing information.

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 DATA-POPUPS

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

Example data balloon

CELL:
1/10th degree cell on the globe

Lat,Lon: Midpoint latitude/longitude of the cell (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.

FolkCodes: Folk codes for sediment texture; repeated.
Syntax: [slightly X) Y-ly Z]; Example: "(s)mG=slightly sandy, mudy, gravel". Specific percentage thresholds apply.

Rock | Gravel|Sand|Mud: RockExposure % |  GravelContent | SandContent | MudContent %

(Max..MinMax..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*:

   
    Number of well-described sites: 3,298,655
             observations (seabed surface):   3,800,691
             contributing datasets:  6,321
             data items: 36,573,740

    Number of cores into subbottom (>10cm penetration): 79,646
   
    Number of  0.1dg cells 
having data:    155,912 (16,797 with no data on texture, coloured 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

Notes:
* These tallies apply to sites giving the information presented here. Many other sites give different
information that is useful for other purpses, for example in geoacoustics, biogeochemistry, sediment transport.
**Although commonly used in papers, the statistic "average minimum distance between cells having data"  is meaningless
because an intense survey of one area will skew the results overall to small distances.



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

CJJ Boulder 04 June 2018