Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance: Ratio of wave- and current-induced shear stress to critical values for oil-sand ball and sediment mobilization

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: P. Soupy Dalyander

Originator: Joseph W. Long

Originator: Nathaniel G. Plant

Originator: David Thompson

Publication_Date: 2012

Title:

Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance: Ratio of wave- and current-induced shear stress to critical values for oil-sand ball and sediment mobilization

Edition: 1.0

Geospatial_Data_Presentation_Form: vector digital data

Series_Information:

Series_Name: Open-File Report (OFR)

Issue_Identification: 2012-1234

Publication_Information:

Publication_Place:

St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL

Publisher: U.S. Geological Survey, Coastal and Marine Geology Program

Online_Linkage: <http://pubs.usgs.gov/of/2012/1234/datafiles.html>

Larger_Work_Citation:

Citation_Information:

Originator: Nathaniel G. Plant

Originator: Joseph W. Long

Originator: P.Soupy Dalyander

Originator: David Thompson

Publication_Date: 2012

Title:

Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance

Edition: 1.0

Series_Information:

Series_Name: Open-File Report (OFR)

Issue_Identification: 2012-1234

Publication_Information:

Publication_Place:

St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL

Publisher: U.S. Geological Survey, Coastal and Marine Geology Program

Online_Linkage: <http://pubs.usgs.gov/of/2012/1234/>

Description:

Abstract:

The U.S. Geological Survey has developed a method for estimating the mobility and potential alongshore transport of heavier-than-water sand and oil agglomerates (tarballs or surface residual balls, SRBs). During the Deepwater Horizon spill, some oil that reached the surf zone of the northern Gulf of Mexico mixed with suspended sediment and sank to form sub-tidal mats. If not removed, these mats can break apart to form SRBs and subsequently re-oil the beach. A method was developed for estimating SRB mobilization and alongshore movement. A representative suite of wave conditions was identified from buoy data for April, 2010, until August, 2012, and used to drive a numerical model of the spatially-variant alongshore currents. Potential mobilization of SRBs was estimated by comparing combined wave- and current-induced shear stress from the model to critical stress values for several sized SRBs. Potential alongshore flux of SRBs was also estimated to identify regions more or less likely to have SRBs deposited under each scenario. This methodology was developed to explain SRB movement and redistribution in the alongshore, interpret observed re-oiling events, and thus inform re-oiling mitigation efforts.

Purpose:

This GIS layer contains an estimate of the ratio of combined wave- and current- induced shear stress in the shallow northern Gulf of Mexico (Alabama and portion of the Florida coast) for a single set of wave conditions to the critical stress of surface residual balls (SRB) of various sizes and local sediment. Values greater than one indicate the threshold for incipient motion is exceeded, and the SRB or sediment is likely mobilized. This output is based on numerical model output of wave and circulation patterns for a given wave height scenario, corresponding to a particular set of offshore wave conditions at NOAA NDBC buoy 42040. The specific wave conditions for a given shapefile are indicated by the file name (of format Hh_Dd_mobile) and may be found by comparing the scenario name (Hh_Dd) to the look-up table included in the GIS zip file, wave_scenarios.txt. Characteristics of SRB classes and the sediment properties used may be found in the look-up table included in the GIS zip file, SRB_casses.txt. This data layer is intended to show regions of likely mobilization for intended use by individuals in SRB mitigation attempting to explain redistribution or burial of SRBs under specific wave conditions.

Supplemental_Information:

This data layer is a subset of USGS Open-File Report 2012-1234, Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance. It is part of a set of data layers describing mobility for a range of wave climate scenarios. The specific wave conditions for this layer are indicated by the file name (of format Hh_Dd_mobile), and in attributes in the shapefile, and may be found by comparing the scenario name (Hh_Dd) to the look-up table included in the GIS zip file, wave_scenarios.txt. SRB class and sediment properties may be found in the look-up table included in the GIS zip file, SRB_casses.txt.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20100401

Ending_Date: 20120801

Currentness_Reference: ground condition

Status:

Progress: Planned

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -88.716961

East_Bounding_Coordinate: -85.412528

North_Bounding_Coordinate: 30.690796

South_Bounding_Coordinate: 29.400356

Keywords:

Theme:

Theme_Keyword_Thesaurus: General

Theme_Keyword: bottom shear stress

Theme_Keyword: U.S. Geological Survey

Theme_Keyword: USGS

Theme_Keyword: Woods Hole Coastal and Marine Science Center

Theme_Keyword: WHCMSC

Theme_Keyword: Coastal and Marine Geology Program

Theme_Keyword: CMGP

Theme_Keyword: wave

Theme_Keyword: current

Theme_Keyword: Delft3D

Theme_Keyword: St. Petersburg Coastal and Marine Science Center

Theme_Keyword: SPCMSC

Theme_Keyword: tarballs

Theme_Keyword: surface residual balls

Theme_Keyword: SRBs

Theme_Keyword: sediment mobility

Theme_Keyword: surf zone

Theme_Keyword: alongshore currents

Theme_Keyword: wave-driven currents

Theme:

Theme_Keyword_Thesaurus: ISO 9115 Topic Category

Theme_Keyword: oceans

Theme_Keyword: oceans and estuaries

Theme_Keyword: oceans and coastal

Theme_Keyword: geoscientificInformation

Place:

Place_Keyword_Thesaurus: General

Place_Keyword: Gulf of Mexico

Place_Keyword: Florida

Place_Keyword: Alabama

Place_Keyword: United States

Place_Keyword: North America

Place_Keyword: Atlantic Ocean

Place_Keyword: Mobile Bay

Place_Keyword: Pensacola Bay

Place_Keyword: Choctawhatchee Bay

Place_Keyword: Santa Rosa

Place_Keyword: Fort Pickens

Place_Keyword: Gulf Shores

Place_Keyword: Panama City

Place_Keyword: Little Lagoon

Stratum:

Stratum_Keyword_Thesaurus: General

Stratum_Keyword: seafloor

Access_Constraints: None

Use_Constraints:

Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: P. Soupy Dalyander

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2290

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: sdalyander@usgs.gov

Browse_Graphic:

Browse_Graphic_File_Name: model_bathymetry.jpg

Browse_Graphic_File_Description:

Graphic showing the numerical model domain over which analysis is conducted.

Browse_Graphic_File_Type: JPEG

Native_Data_Set_Environment:

Microsoft Windows Vista Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 9.3.1.4095

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The attributes in this data layer corresponds to the ratio of combined wave-current shear stress to the critical stress value for surface residual balls (SRBs) and sediment of a particular size and density (specific parameters may be found in the included SRB_classes.txt files) for the wave conditions of Hh_Dd, characteristics of which may be found in the included wave_scenarios.txt file. Statistical values will vary if a different numerical model is used for the hydrodynamics, or if a different method is used in calculating wave-current stress or critical stress.

Logical_Consistency_Report:

No duplicate features are present. All polygons are closed, and all lines intersect where intended. No undershoots or overshoots are present.

Completeness_Report:

This statistic was calculated at all locations (wet grid cells) where model output exists. Because of differences between the scenarios, not all grid cells may be included in all scenarios. The statistic was calculated for a particular scenario (Hh_Dd), the characteristics of which may be found in the included wave_scenarios.txt file, and for sediment and various classes of SRBs, the characteristics of which may be found in the included SRB_classes.txt file. The bottom shear stress was calculated from wave and current estimates generated with Delft3D, and would vary if different models were used or if different model inputs (such as bathymetry, forcing winds, and boundary conditions) or parameterizations were chosen. Calculated currents were depth-averaged and therefore the calculated mobility values are expected to be most valid in well-mixed regions, e.g., the surf zone. Mobility estimates would vary for different size or density objects and/or if a different formulation for calculating the critical stress value is used.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Numerical models are used in the generation of hydrodynamic conditions used in creating this data layer. Because the overall horizontal accuracy of the data set depends on the accuracy of the model, the underlying bathymetry, forcing values used, and so forth, the spatial accuracy of this data layer cannot be meaningfully quantified.

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: NOAA National Centers for Environmental Prediction (NCEP)

Publication_Date: 20110601

Title: NOAA/NCEP Global Forecast System (GFS) Atmospheric Model

Publication_Information:

Publication_Place: Camp Springs, MD

Publisher: NOAA National Centers for Environmental Prediction

Online_Linkage: <http://nomads.ncdc.noaa.gov/data.php>

Type_of_Source_Media: online

Source_Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20100401

Ending_Date: 20120531

Source_Currentness_Reference: publication date

Source_Citation_Abbreviation: NOAA GFS

Source_Contribution:

Wind speed data at 10 m above the sea surface from the NOAA Global Forecast System (GFS) 0.5 degree model is interpolated by NOAA to the 4' Wavewatch3 grid and archived. These archived data are used to drive the numerical wave and circulation model that creates estimated of bottom shear stress.

Source_Information:

Source_Citation:

Citation_Information:

Originator: NOAA National Centers for Environmental Prediction (NCEP

Publication_Date: 20121001

Title: NOAA/NWS/NCEP 4' Wavewatch III Operational Wave Forecast

Publication_Information:

Publication_Place: Camp Springs, MD

Publisher: NOAA National Centers for Environmental Prediction

Online_Linkage: <http://polar.ncep.noaa.gov/waves/index2.shtml>

Type_of_Source_Media: online

Source_Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20100401

Ending_Date: 20120531

Source_Currentness_Reference: publication date

Source_Citation_Abbreviation: NOAA WW3

Source_Contribution:

Boundary conditions for the wave model were provided by the 4' NOAA/NWS/NCEP Wavewatch III operational ocean wave forecast.

Process_Step:

Process_Description:

The D-Flow and D-Waves components of the Deltares Delft3D numerical model suite (version 4.00.01) were used to estimate bottom orbital velocity, peak period, peak wave direction, and east and north components of wind and wave-driven velocity for the offshore wave conditions corresponding this scenario Hh_Dd (characteristics of which may be found in the included wave_scenarios.txt file) in each grid cell in the model domain. The wave model D-Waves, based on the Simulating WAves Nearshore (SWAN) model, is a 3rd generation phase-averaged numerical wave model which conserves wave energy subject to generation, dissipation, and transformation processes and resolves spectral energy density over a range of user-specified frequencies and directions. D-Wave was used in stationary mode. D-Flow solves the shallow water Navier Stokes equations and is run in 2-D depth-averaged mode, with linkage to D-Waves allowing the generation of wave-driven currents via wave radiation stress forcing. Default values for model parameters governing horizontal viscosity, bottom roughness, and wind drag were used. Neumann boundary conditions were used along the east, west, and south model boundaries with harmonic forcing set to zero. Model bathymetry was provided by the NOAA National Geophysical Data Center Northern Gulf Coast digital elevation map, referenced to NAVD88.

Significant wave height, dominant wave period, and wave direction were prescribed as D-Wave TPAR format files every 30 grid cells along the model boundary using results from the NOAA Wavewatch III 4' multi-grid model for a representative moment in time corresponding to the offshore wave conditions of the scenario, the specific time of which may be found in the included wave_scenarios.txt file. A JONSWAP (JOint NOrth Sea WAve Project) spectral shape was assumed at these boundary points. Wind forcing was provided using the archived WavewatchIII 4' winds, extracted from the NOAA GFS wind model, for this time. The D-Wave directional space covers a full circle with a resolution was 5 degrees (72 bins). The frequency range was specified as 0.05-1 Hz with logarithmic spacing. Bottom friction calculations used the JONSWAP formulation with a uniform roughness coefficient of 0.067 m2/s3. 3rd-generation physics are activated which accounts for wind wave generation, triad wave interactions and whitecapping (via the Komen et al parameterization). Depth-induced wave breaking dissipation is included using the method of Battjes and Janssen with default values for alpha (1) and gamma (0.73). Wave model outputs of bottom orbital velocity, peak period, and peak wave direction were extracted on the wave model grid, and current model outputs of east and north current velocity component were extracted and interpolated to the wave model grid (staggered points in relation to the current model grid).

NDBC observations from station 42012 for the representative scenario time periods were used to validate the wave model results.

Source_Used_Citation_Abbreviation: NOAA GFS

Source_Used_Citation_Abbreviation: NOAA WW3

Process_Date: 2012

Source_Produced_Citation_Abbreviation: DELFT3D

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: Joseph W. Long

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 600 4th Street S

City: St. Petersburg

State_or_Province: FL

Postal_Code: 33701

Country: USA

Contact_Voice_Telephone: (727) 803-8747 x3024

Contact_Facsimile_Telephone: (727) 803-2032

Contact_Electronic_Mail_Address: jwlong@usgs.gov

Process_Step:

Process_Description:

Use the wave model and current model results to calculate the bottom shear stress within each model grid cell using Mathworks MATLAB software (v2012A). The wave-current stress was calculating following the method of Soulsby (1995) to parameterize four methods giving good overall performance for estimating wave-current stress, based on original formulations by Grant and Madsen (1979), Fredsøe (1984), Huynh-Thanh and Temperville (1991), and Davies et al. (1998). The combined wave-current stress for the individual components of wave and current stress was calculated for hydrodynamic model output following the method prescribed in Soulsby (1997) for each of the four methods. The mean value of the four methodologies was used to estimate the combined wave-current shear stress for the hydrodynamic scenario. Wave direction, bottom orbital velocity, and period, and depth-averaged current magnitude and direction, required for this calculation, are calculated internally by the model. The roughness used is 1/12 the diameter of the SRB or sediment being analyzed, following Soulsby (1997). Stress values are saved in MATLAB .mat format.

The same individual who completed this processing step completed all additional processing steps.

References: Davies, A.G., Soulsby, R.L., King, H.L. (1988). A numerical model of the combined wave and current bottom boundary layer. J. Geophys. Res. 93, 491-508.

Fredsøe, J. (1984). Turbulent boundary layer in wave-current motion. J. Hydraul. Eng. ASCE (110), 1103-1120.

Grant, W.D., Madsen, O.S. (1979). Combined wave and current interaction with a rough bottom. J. Geophys. Res. (84), 1797-1808.

Huynh-Thanh, S., Temperville, A. (1991). A numerical model of the rough turbulent boundary layer in combined wave and current interaction, in Sand Transport in Rivers, Estuaries, and the Sea, eds. R. L. Soulsby and R. Bettess, pp 93-100. Balkema, Rotterdam.

Soulsby, R.L. (1995). Bed shear-stresses due to combined waves and currents, in Advances in Coastal Morphodynamics, eds. M.J.F. Stive, H.J. de Vriend, J. Fredsøe, L. Hamm, R.L. Soulsby, C. Teisson and J.C. Winterwerp, pp. 4-20 and 3-23. Delft Hydraulics, Netherlands.

Soulsby, R.L. (1997). Dynamics of Marine Sands. Thomas Telford Publications: London, 249 pp.

Source_Used_Citation_Abbreviation: DELFT3D

Process_Date: 2012

Source_Produced_Citation_Abbreviation: WC STRESS

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: P. Soupy Dalyander

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02540

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2290

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: sdalyander@usgs.gov

Process_Step:

Process_Description:

Estimate the critical shear stress for 300 micron quartz sediment and 6 SRB size classes and take the ratio of the combined wave-current stress to this critical value at each grid point. The specific characteristics for the sediment and SRB classes may be found in the included SRB_classes.txt file. Calculations are performed in Mathworks MATLAB (v2012A). Critical stress thresholds are calculated using the Shield's parameter following Soulsby (1997) and saved in MATLAB .mat format. In the case of SRBs, the Shield's parameter is identified as a "high" critical stress value, corresponding to instances when an SRB of the identified size is within a uniform bed of similarly sized SRBs. Exposure above the bed, such as may occur with a single SRB on a sand band, reduces the critical shear stress value for incipient motion. Based on field observations of gravel and sand mixtures, a "medium" critical stress value is calculated from a constant non-dimensional Shields parameter of 0.02, and a "low" critical stress value is calculated from a constant non-dimensional Shields parameter of 0.01 (Andrews, 1983; Bottacin-Busolin et al, 2008; Fenton and Abbott, 1977; Wiberg and Smith, 1987; Wilcock, 1998). Because the in-situ sediment is assumed to be of a relatively uniform size, a single critical stress value based on the Shields parameter is used.

References:

Andrews, E.D. (1983). Entrainment of gravel from naturally sorted riverbed material. Geo. Soc. Amer. Bull. (94), 1225-1231.

Bottacin-Busolin, A., Tait, S.J., Marion, A., Chegini, A., Tregnaghi, M. (2008). Probabilistic description of grain resistance from simultaneous flow field and grain motion measurements. Water Resources Res. (44), WO9419.

Fenton, J.D., Abbott, J.E. (1977). Initial movement of grains on a stream bed: the effect of relative protusion. Proc. R. Soc. Lond. A. (352), 523-537.

Soulsby, R., 1997. Dynamics of Marine Sands, a Manual for Practical Applications. Thomas Telford Publications, London.

Wibert, P.L., Smith, J.D. (1987). Calculations of the Critical Shear Stress for Motion of Uniform and Heterogenous Sediments. Water Resources Res. (23), 1471-1480.

Wilcock, P.R. (1998). Two-Fraction Model of Initial Sediment Motion in Gravel-Bed Rivers. Science (280), 410-412.

Source_Used_Citation_Abbreviation: WC STRESS

Process_Date: 2012

Source_Produced_Citation_Abbreviation: RATIO

Process_Step:

Process_Description:

Export the values for each grid cell from MATLAB format into an ArcGIS shapefile using the Mathworks MATLAB Mapping Toolbox (v2012A). Land grid cells are not exported to Arc. The shapefile is written with the "shapewrite" command. Because MATLAB does not assign a projection, the projection corresponding to the projection associated with the bathymetry used in the numerical models is added in ArcCatalog 9.3. The file was then quality checked in ArcMap to insure values were properly exported to the shapefile from MATLAB.

Source_Used_Citation_Abbreviation: RATIO

Process_Date: 2012

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference: Gulf of Mexico

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: G-polygon

Point_and_Vector_Object_Count: 661210

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Geographic:

Latitude_Resolution: 0.000001

Longitude_Resolution: 0.000001

Geographic_Coordinate_Units: Decimal degrees

Geodetic_Model:

Horizontal_Datum_Name: D_WGS_1984

Ellipsoid_Name: WGS_1984

Semi-major_Axis: 6378137.000000

Denominator_of_Flattening_Ratio: 298.257224

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988

Altitude_Resolution: 0.01 m

Altitude_Distance_Units: meters

Altitude_Encoding_Method:

Explicit elevation coordinate included with horizontal coordinates

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label: Hh_Dd_mobility

Entity_Type_Definition:

Ratio of wave- and current-induced shear stress to critical values for oil-sand ball and sediment mobilization for specific wave scenarios

Entity_Type_Definition_Source: USGS

Attribute:

Attribute_Label: FID

Attribute_Definition: Internal feature number.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain:

Sequential unique whole numbers that are automatically generated.

Attribute:

Attribute_Label: Shape

Attribute_Definition: Feature geometry.

Attribute_Definition_Source: ESRI

Attribute_Domain_Values:

Unrepresentable_Domain: Coordinates defining the features.

Attribute:

Attribute_Label: Scenario_H

Attribute_Definition:

Scenario wave height number (e.g., "h" in Hh_Dd, see wave_scenarios.txt)

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 1

Range_Domain_Maximum: 5

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 1

Attribute:

Attribute_Label: Scenario_D

Attribute_Definition:

Scenario wave direction number (e.g., "d" in Hh_Dd, see wave_scenarios.txt)

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 1

Range_Domain_Maximum: 16

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 1

Attribute:

Attribute_Label: sediment

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress to the critical stress for 300 micron quartz sand calculated from the Shield's parameter. Values greater than one indicate sand is likely mobilized under the wave conditions associated with this scenario.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB1_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 1 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB1_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 1 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB1_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 1 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB2_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 2 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB2_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 2 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB2_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 2 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB3_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 3 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB3_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 3 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB3_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 3 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB4_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 4 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB4_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 4 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB4_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 4 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB5_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 5 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB5_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 5 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB5_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 5 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB6_high

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 6 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relatively high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB6_med

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 6 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Attribute:

Attribute_Label: SRB6_low

Attribute_Definition:

Unitless ratio of the combined wave- and current-induced shear stress for this scenario to the critical stress for SRB class 6 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.

Attribute_Definition_Source: USGS

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum: 0

Range_Domain_Maximum: 100

Attribute_Units_of_Measure: non-dimensional

Attribute_Measurement_Resolution: 0.01

Distribution_Information:

Distributor:

Contact_Information:

Contact_Person_Primary:

Contact_Person: P. Soupy Dalyander

Contact_Organization: U.S. Geological Survey

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Road

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2290

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: sdalyander@usgs.gov

Resource_Description:

Hh_Dd_mobility.shp: ratio of combined wave- and current-induced shear stress for Hh_Dd scenario to critical stress for sediment and various size SRBs (see SRB_classes.txt). NOTE: Specific layer name indicates the scenario (Hh_Dd) for the layer, with specific characteristics given in the included wave_scenarios.txt.

Distribution_Liability:

Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials.

Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: SHP

Format_Version_Number: 3.3

Format_Specification: ESRI shapefile

Format_Information_Content:

WinZip archive file containing the shapefile components. The WinZip file also includes FGDC compliant metadata.

File_Decompression_Technique: WinZip 12.0 archive

Transfer_Size: 60-70 MB

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name: <http://pubs.usgs.gov/of/2012/1234/datafiles.html>

Fees: None

Technical_Prerequisites:

These data are available in Environmental Systems Research Institute (ESRI) shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from ESRI at www.esri.com.

Metadata_Reference_Information:

Metadata_Date: 20121211

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: U.S. Geological Survey

Contact_Person: P. Soupy Dalyander

Contact_Position: Oceanographer

Contact_Address:

Address_Type: mailing and physical address

Address: 384 Woods Hole Role

City: Woods Hole

State_or_Province: MA

Postal_Code: 02543-1598

Country: USA

Contact_Voice_Telephone: (508) 548-8700 x2290

Contact_Facsimile_Telephone: (508) 457-2310

Contact_Electronic_Mail_Address: sdalyander@usgs.gov

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time

Metadata_Access_Constraints: None

Metadata_Use_Constraints: None

Metadata_Extensions:

Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>

Profile_Name: ESRI Metadata Profile