50-Meter Digital Elevation Model of Coastal Bathymetry Collected in 2012
from the Chandeleur Islands, Louisiana (U.S. Geological Survey Field Activity
Numbers 12BIM03 and 12BIM04)
Metadata:
- Identification_Information:
-
- Citation:
-
- Citation_Information:
-
- Originator: U.S. Geological Survey
- Publication_Date: 2014
- Title:
- 50-Meter Digital Elevation Model of Coastal Bathymetry Collected in
2012 from the Chandeleur Islands, Louisiana (U.S. Geological Survey
Field Activity Numbers 12BIM03 and 12BIM04)
- Geospatial_Data_Presentation_Form: raster digital data
- Online_Linkage: https://pubs.usgs.gov/ds/847/data/raster/Chan12_DEM.zip
- Larger_Work_Citation:
-
- Citation_Information:
-
- Originator: Nancy T. DeWitt
- Originator: Julie C. Bernier
- Originator: William R. Pfeiffer
- Originator: Jennifer L. Miselis
- Originator: James G. Flocks
- Originator: B.J. Reynolds
- Originator: Dana S. Wiese
- Originator: Kyle W. Kelso
- Publication_Date: 2014
- Title:
- Coastal Bathymetry Data Collected in 2012 from the Chandeleur
Islands, Louisiana
- Geospatial_Data_Presentation_Form: multimedia
presentation
- Series_Information:
-
- Series_Name: U.S. Geological Survey Data Series
- Issue_Identification: 847
- Publication_Information:
-
- Publication_Place: St. Petersburg, FL
- Publisher: U.S. Geological Survey
- Online_Linkage: https://pubs.usgs.gov/ds/847
- Description:
-
- Abstract:
- As part of the Barrier Island Evolution Research Project, scientists
from the U.S. Geological Survey's St. Petersburg Coastal and Marine
Science Center conducted nearshore geophysical surveys off the northern
Chandeleur Islands, Louisiana, in Julyof 2012. The overall objective of
the study is to better understand barrier-island geomorphic evolution,
particularly storm-related depositional and erosional processes that shape
the islands over annual to interannual timescales (1-5 years). The
collection of geophysical data will allow us to identify relationships
between the geologic history of the island and its present day morphology
and sediment distribution. This mapping effort was the first in a series
of three planned surveys in this area. High resolution geophysical data
collected in each of 3 consecutive years along this rapidly changing
barrier-island system will provide a unique time-series dataset that will
significantly further the analyses and geomorphological interpretations of
this and other coastal systems, improving our understanding of coastal
response and evolution over short time scales (1-5 years). This report
serves as an archive of processed interferometric swath and single-beam
bathymetry data that were collected during two cruises (USGS Field
Activity Numbers 12BIM03 and 12BIM04) along the northern portion of the
Chandeleur Islands, Breton National Wildlife Refuge, Louisiana, in July of
2012. Geographic information system data products include a 50 m-cell-size
interpolated bathymetry grid surface, trackline maps, and point data
files. Additional files include error analysis maps, Field Activity
Collection System logs, and formal Federal Geographic Data Committee
metadata.
- Purpose:
- This 50-meter cell size digital elevation model is an interpretive
product that was derived from the processed single-beam and
interferometric swath bathymetry data collected in July of 2012 around the
northern Chandeleur Islands, Louisiana.
- Supplemental_Information:
- Both the single-beam and swath surveys were acquired and processed to
a geodetic reference ellipsoid. The swath survey used OmniSTAR High
Precision for the Differential Geographic Positioning System (DGPS) at
datum ITRF2005, and the single-beam post-processed DGPS navigation was
referenced to WGS84 (G1150)/ITRF00. Both datasets were transformed
horizontally to NAD83 and then vertically to NAVD88 using GEOID09 (NOAA
NGS VDatum software version 3.2 - http://vdatum.noaa.gov/) and the final
x,y,z position data from each survey were merged to generate a digital
elevation model with a resolution of 50-meter cell size.
- Time_Period_of_Content:
-
- Time_Period_Information:
-
- Range_of_Dates/Times:
-
- Beginning_Date: 20120712
- Ending_Date: 20120804
- Currentness_Reference: ground condition
- Status:
-
- Progress: Complete
- Maintenance_and_Update_Frequency: none
- Spatial_Domain:
-
- Bounding_Coordinates:
-
- West_Bounding_Coordinate: -88.916815
- East_Bounding_Coordinate: -88.795726
- North_Bounding_Coordinate: 30.096010
- South_Bounding_Coordinate: 29.908091
- Keywords:
-
- Theme:
-
- Theme_Keyword_Thesaurus: ISO 19115 Topic Category
- Theme_Keyword: elevation
- Theme_Keyword: geoscientificInformation
- Theme_Keyword: imageryBaseMapsEarthCover
- Theme_Keyword: oceans
- Theme:
-
- Theme_Keyword_Thesaurus: General
- Theme_Keyword: marine geology
- Theme_Keyword: bathymetry
- Theme_Keyword: interferometry
- Theme_Keyword: swath
- Theme_Keyword: CARIS
- Theme_Keyword: HIPS and SIPS
- Theme_Keyword: single beam
- Theme_Keyword: echosounder
- Theme_Keyword: Knudsen
- Theme_Keyword: 320 BathyProfiler
- Theme_Keyword: hydrography
- Theme_Keyword: geophysical
- Theme_Keyword: U.S. Geological Survey
- Theme_Keyword: USGS
- Theme_Keyword: Coastal and Marine Geology Program
- Theme_Keyword: CMGP
- Theme_Keyword: St. Petersburg Coastal and Marine Science
Center
- Theme_Keyword: SPCMSC
- Theme_Keyword: Barrier Island Evolution Research Project
- Theme_Keyword: Barrier Island Mapping
- Theme_Keyword: 12BIM03
- Theme_Keyword: 12BIM04
- Place:
-
- Place_Keyword_Thesaurus: Geographic Names Information
System (GNIS)
- Place_Keyword: Chandeleur Islands
- Place_Keyword: Gulf of Mexico
- Place_Keyword: Chandeleur Sound
- Place_Keyword: Louisiana
- Access_Constraints: None
- Use_Constraints:
- The U.S. Geological Survey requests that it be referenced as the
originator of this dataset in any future products or research derived from
these data. These data should not be used for navigational purposes.
- Point_of_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy T. DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: Mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address: ndewitt@usgs.gov
- Data_Set_Credit:
- U.S. Geological Survey, Coastal and Marine Geology Program, St.
Petersburg Coastal and Marine Science Center
- Native_Data_Set_Environment:
- Microsoft Windows 7 Service Pack 1; Esri ArcGIS 10.1 SP1 (Build 3143)
- Data_Quality_Information:
-
- Attribute_Accuracy:
-
- Attribute_Accuracy_Report:
- The accuracy of the data is determined during data collection. The
single-beam and interferometric swath bathymetry data were collected
during concurrent research cruises in July, 2012. Methods are employed to
maintain data collection consistency aboard various platforms. During
mobilization, each piece of equipment, single-beam and swath, is isolated
to obtain internal and external offset measurements with respect to the
survey platform. All critical measurements are recorded manually and
digitally and entered into their respective programs for calibration. Once
calibration is complete and the calibration status is considered
acceptable, survey operations commence. Each system has a dedicated
computer, and efforts are made to use the same equipment and software
versions on both systems. However, upgrades and changes can occur and
require additional setup, measurements, and notation. For single-beam
bathymetry, offsets between the single beam transducers and the Ashtech
antenna reference point (ARP) were measured and accounted for in
post-processing. Bar checks were performed as calibration efforts and
accounted for any drift in the echosounder. Differential Geographic
Positioning System (DGPS) coordinates were obtained using post-processing
software packages (National Geodetic Survey On-Line Positioning User
Service, OPUS, and Waypoint Product Group GrafNav, version 8.3). For the
interferometric swath bathymetry, offsets between the sonar head and the
DGPS antennas were measured and entered into the CodaOctopus F190R
internal setup program. DGPS was provided through the OmniSTAR High
Performance wide-area GPS service. DGPS is always implemented for
navigational accuracy either during acquisition or as a post-processing
step. These bathymetric data have not been independently verified for
accuracy.
- Logical_Consistency_Report:
- The single-beam and interferometric swath bathymetry data were collected
during concurrent research cruises in July, 2012. Refer to the online data
series linkage for field logs, vessel platform descriptions, and other
survey information. This dataset was created to provide a single
post-processed bathymetric grid from the merged datasets. The digital
elevation model is 50-meter cell-size resolution; data gaps between
acquisition tracklines are predicted values generated by the gridding
algorithm.
- Completeness_Report:
- This is a completely processed digital elevation model representing an
interpolated bathymetric surface derived from the acoustic interferometric
swath and single-beam bathymetry data.
- Positional_Accuracy:
-
- Horizontal_Positional_Accuracy:
-
- Horizontal_Positional_Accuracy_Report:
- All static base station sessions were processed through the On-Line
Positioning User Service (OPUS) maintained by the National Oceanic and
Atmospheric Administration (NOAA) and the National Geodetic Survey
(NGS). The base location results from OPUS were entered into a
spreadsheet to compute a final, time-weighted positional
coordinate-latitude, longitude, and ellipsoid height-. Base station
positional error for each GPS session was calculated as the absolute
value of the final position minus the session position value. The
maximum horizontal error of the base station coordinates used for
post-processing the single-beam bathymetry was 0.00042 seconds latitude
and 0.00096 seconds longitude for TMRK and 0.00036 seconds latitude and
0.00047 seconds longitude for BERM. The stated horizontal accuracy of
the OmniSTAR HP navigation subscription used during swath bathymetry
acquisition is reported by the service as +/-15 centimeters (cm)(95
percent of the time).
- Quantitative_Horizontal_Positional_Accuracy_Assessment:
-
- Horizontal_Positional_Accuracy_Value: 0.00000 - 0.00042
- Horizontal_Positional_Accuracy_Explanation: latitude
decimal seconds
- Quantitative_Horizontal_Positional_Accuracy_Assessment:
-
- Horizontal_Positional_Accuracy_Value: 0.00000 - 0.00096
- Horizontal_Positional_Accuracy_Explanation: longitude
decimal seconds
- Vertical_Positional_Accuracy:
-
- Vertical_Positional_Accuracy_Report:
- All static base station sessions for TMRK and BERM were processed
through the On-Line Positioning User Service (OPUS) maintained by the
National Oceanic and Atmospheric Administration (NOAA) and the National
Geodetic Survey (NGS). The base location results from OPUS were entered
into a spreadsheet to compute a final, time-weighted positional
coordinate-latitude, longitude, and ellipsoid height. Base station
positional error for each GPS session was calculated as the absolute
value of the final position minus the session position value. SPCMSC
standards define the maximum acceptable vertical error for any
individual base station GPS session as less than or equal to 3 times the
standard deviation of the ellipsoid height; any occupations exceeding
this error are removed and the base station coordinates are
recalculated. For the TMRK base location the standard deviation of the
ellipsoid height was 0.014 m, and the maximum difference from the
average ellipsoid for any GPS session was +/- 0.030 m. For BERM base
location the standard deviation of the ellipsoid height was 0.021 m and
the maximum difference from the average ellipsoid for any GPS session
was +/- 0.031 m. All the processed single-beam bathymetry data (x,y,z)
for 2012 are referenced to these base station coordinates. The
differentially corrected navigation files-base station GPS processed to
boat GPS- were exported from GrafNav and then imported into CARIS HIPS
and SIPS version 7.1, and then merged, by time, with the HYPACK (version
10.0.5.31) raw data files, at which point the soundings were
geometrically corrected for motion and speed of sound. For the
single-beam soundings, elevation differences at all trackline crossings
were less than or equal to 0.14 m, and the elevation differences were
within +/- 0.10 m for 89.28 percent of the 653 crossings. The stated
vertical accuracy of the OmniSTAR HP navigation subscription used during
swath bathymetry acquisition is +/-0.15 m (95 percent of the time). The
Coda Octopus F190R IMU, which integrates the OmniSTAR HP position with
motion, measures vessel velocity (+/- 0.014 meters/second (m/s)), roll
and pitch (< 0.025 degrees), heading (1 m baseline 0.1 degrees), and
heave (5 cm per meter (m) of depth). The vertical accuracy for the
SWATHplus-H system varies with depth and across track range. At 57 m it
is accurate to 10 cm vertically. Maximum vertical transformation error
reported by VDatum is 0.171 m or 17.1 cm for eastern Louisiana. The sum
of the errors (+/- 0.031 m plus +/-0.15 m plus 0.171 m) in the vertical
is equal to +/-.352 m or +/- 35.2 cm.
- Lineage:
-
- Process_Step:
-
- Process_Description:
- GPS Acquisition: A GPS base station was erected at a temporarily
installed USGS benchmark (TMRK) located on the sound side of the
Chandeleur Islands. A second base station (BERM) was erected on the
furthest northern island, providing differential GPS coverage for the
survey area within a 15 kilometer (km) radius of either benchmark. GPS
receivers recorded the 12-channel full-carrier- phase positioning
signals (L1/L2) from satellites via the Thales choke-ring antenna at the
base stations. This GPS instrument combination was duplicated on the
single-beam survey vessel (rover). The base receiver and the rover
receiver record their positions concurrently at 1-second (s) recording
intervals throughout the survey.
- Process_Date: 2012
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy T. DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Single-Beam Bathymetry Acquisition: The single-beam bathymetric data
were collected aboard the 22-foot RV TwinVee. Boat motion was recorded
at 50-millisecond (ms) intervals with a Teledyne TSS Dynamic Motion
Sensor (TSS DMS-05). HYPACK version 10.0.5.31, a marine surveying,
positioning, and navigation software package, managed the
planned-transect information and provided real-time navigation,
steering, correction, data quality, and instrumentation-status
information to the boat operator. Depth soundings were recorded at 50 ms
intervals with a Knudsen 320BP echosounder system using a 200 kilohertz
(kHz) transducer. Data from the GPS receiver, motion sensor, and
fathometer were recorded in real-time and merged into a single raw data
file (.raw) in HYPACK. Each device string was referenced by a device
identification code and time stamped to UTC. Sound velocity measurements
were collected using an Applied Microsystems Smart Sound Velocity
Profiler (SVP). The instrument was cast overboard periodically,
throughout the survey, to observe changes in water column speed of sound
(SOS).
- Process_Date: 2012
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy T. DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Swath Bathymetry Acquisition: The interferometric swath bathymetry
data were collected aboard the RV Survey Cat using a SEA SWATHplus-H 468
kHz interferometric sonar system mounted on a sled attached to a rail
system, which was fastened between the catamaran halls. This allowed the
instrument to align directly below the GPS antennae and minimize
geometry errors. Boat position and motion data were recorded in
real-time with a CodaOctopus F190R wetpod inertial measurement unit(IMU)
mounted underwater between the transducer heads, to minimize lever arm
geometry errors between the observed depths and associated vessel
motion. Real-time corrected positions were acquired with an OmniSTAR HP
(High-Precision differential global navigation satellite system)
satellite constellation subscription. OmniSTAR HP position correction
data and motion data from the IMU were integrated with interferometric
soundings in the SWATHplus software package versions 3.7.17, with
positional and calibration offsets pre-defined by a session file(.sxs),
allowing for real-time- corrected depths. Prior to deployment, all
equipment offsets were surveyed in dry dock with a laser total station.
During the survey, all swath tracklines were recorded in SEA SWATHplus
raw data format (.sxr). A Valeport Mini Sound Velocity Sensor (SVS) was
attached to the transducer mount and collected continuous speed of sound
(SOS) measurements at the depth of the transducers. These values were
directly read and incorporated into the SWATHplus acquisition software,
giving real-time speed of sound at the transducer while underway. In
addition, a separate sound velocity profiler (Valeport miniSVP) was used
to collect SOS profiles (water surface to seafloor) at intervals
throughout the survey.
- Process_Date: 2012
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy T. DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Swath Bathymetry Processing: Position data recorded by the
Coda-Octopus F190R IMU system were corrected in real time via the
OmniSTAR HP differential navigation system. The IMU applied real-time
motion corrections for heave, roll, and pitch to the vertical component
of each position fix. The corrected positions were integrated with the
observed bathymetric values to calculate a final ellipsoid height and
position, representing the elevation of the seafloor with respect to the
geodetic reference frame ITRF05 across the swath range. SWATHplus served
as both an acquisition software and initial processing software.
Preliminary roll calibration trackline data were collected and processed
with Systems Engineering and Assessment Ltd SWATHplus and Grid Processor
software version 3.7.17. Instrument offset and calibration values were
entered into the session file (.sxs) and the raw data files (.sxr) were
processed using the updated system configuration containing roll
calibration values, measured equipment offsets, acquisition parameters,
navigation and motion from the F190R, SOS at the sonar head, and SVP
cast data. Any calibration offsets or acoustic filtering applied in
SWATHplus was also written to the processed data file (.sxp). The
initial real-time processing datum for the swath and backscatter data
was ITRF05, which is the acquisition datum for OmniSTAR HP position and
navigation data. Processed data files were imported into CARIS HIPS and
SIPS version 7.1, and original sounding data were edited for outliers
using the program's depth filters and reference surfaces. Remaining
outliers were deleted out manually. A CARIS Bathymetry with Associated
Statistical Error (BASE) surface with associated Combined Uncertainty
and Bathymetry Estimator(CUBE) sample surface was created from the
edited soundings dataset. A BASE hypothesis is the estimated value of a
grid node representing all soundings within a chosen resolution or
grid-cell size (for example, 5 m) weighted by uncertainty and proximity,
giving the final value as a "sample" of the data within the specific
grid cell. This algorithm allows for multiple grid-node hypotheses to be
verified or overridden by the user, while maximizing processing
efficiency. A 5-m resolution CUBE surface was created to perform initial
hypothesis editing using the CARIS Subset Editor tool, followed by
higher resolution surface detail editing within the subset editor. The
sample x,y,z data were exported as ASCII text at a 5-m by 5-m sample
resolution in the ellipsoid datum of ITRF05.
- Process_Date: 2013
- Source_Produced_Citation_Abbreviation:
12BIM03_IFB_04_005_ITRF05.txt
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Differentially Corrected Navigation Processing: The coordinate
values of the GPS base station (TMRK) are the time-weighted average of
values obtained from the National Geodetic Survey's On-Line Positioning
User Service (OPUS). The base station coordinates were imported into
GrafNav version 8.1 (Waypoint Product Group) and the kinematic GPS data
from the survey vessel were post-processed to the concurrent GPS session
data at the base stations. During processing, steps were taken to ensure
that trajectories between the base and the rover were clean, resulting
in fixed positions. By analyzing the graphs, trajectory maps, and
processing logs that GrafNav produces for each GPS session, GPS data
from satellites flagged by the program as having poor health or
satellite time segments that had cycle slips could be excluded, or the
satellite elevation mask angle could be adjusted to improve the position
solutions. The final differentially corrected precise DGPS positions
were computed at 1-second (s) intervals for each rover GPS session and
exported in ASCII text format to replace the uncorrected real-time rover
positions recorded during acquisition. The GPS data were processed and
exported in World Geodetic System of 1984 (WGS84) (G1150) geodetic
datum.
- Process_Date: 2013
- Source_Produced_Citation_Abbreviation:
- Post-processed differential navigation data for the rover (boat) in
ASCII text format. 3 files-forward, reverse, and combined trajectories-
are produced for each GPS session file.
- Process_Step:
-
- Process_Description:
- Single-beam bathymetry processing: All data were processed with
CARIS HIPS and SIPS (Hydrographic Information Processing System and
Sonar Information Processing System) version 7.1. The raw HYPACK
(version 10.0.5.31) data files were imported into CARIS; the
differentially corrected navigation files were imported using the
generic data parser tool within CARIS; and any SVP profile casts were
entered and edited using the SVP editor within CARIS. The bathymetric
data components-position, motion, depth, and SOS- were merged and
geometrically corrected in CARIS to produce processed x,y,z data. Next
the data were edited for outliers and further reviewed in the Subset
Editor utility for crossing status, and questionable data points or
areas. The geometrically corrected point data were then exported as an
x,y,z ASCII text file referenced to WGS84(G1150), which is equivalent to
ITRF00, and ellipsoid height in meters.
- Source_Used_Citation_Abbreviation:
- Post-processed differential navigation data and raw HYPACK
bathymetric data in ASCII text format.
- Process_Date: 20120601
- Source_Produced_Citation_Abbreviation:
12BIM04_SBB_ITRF00_03_xxx.txt
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Datum transformation: Using the transformation software VDatum
version 3.2, both the interferometric swath and single-beam bathymetric
data were transformed horizontally from their data acquisition
datums-swath, ITRF05; single-beam, ITRF00- to the North American Datum
of 1983 (NAD83) reference frame and the orthometric vertical datum
NAVD88 using the National Geodetic Survey (NGS) geoid model of 2009
(GEOID09).
- Source_Used_Citation_Abbreviation:
12BIM03_IFB_04_005_ITRF05.txt
- Source_Used_Citation_Abbreviation:
12BIM04_SBB_ITRF00_03_xxx.txt
- Process_Date: 2013
- Source_Produced_Citation_Abbreviation:
12BIM03_IFB_NAD83_NAVD88_GEOID09.txt
- Source_Produced_Citation_Abbreviation:
12BIM04_SBB_NAD83_NAVD88_GEOID09.txt
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Process_Step:
-
- Process_Description:
- Gridding Bathymetric data: Using Esri ArcGIS version 10.1, the swath
and the single-beam elevations were examined for spatial distribution
and vertical agreement. After combining the point data (x,y,z), a
triangulated irregular network (TIN) was generated. The TIN surface and
elevation point- shapefile were used in conjunction to visually scan for
any remaining discrepancies. Once all data were reviewed, a 50-m by 50-m
cell resolution digital elevation model (DEM) was generated using the
natural neighbor algorithm in ArcGIS software. A raster mask was created
from the polygon survey extent with the ArcGIS "polygon to raster"
conversion tool. The DEM was then clipped to the raster mask using the
ArcGIS Spatial Analyst "extract by raster mask" tool. To help reduce
uncertainty in the final DEM, the ArcGIS Spatial Analyst "neighborhood"
low pass raster-data filter was applied.
- Source_Used_Citation_Abbreviation:
12BIM03_IFB_NAD83_NAVD88_GEOID09.txt
- Source_Used_Citation_Abbreviation:
12BIM04_SBB_NAD83_NAVD88_GEOID09.txt
- Process_Date: 2013
- Source_Produced_Citation_Abbreviation:
Chandeleurs_2012_50_NAD83_NAVD88_GEOID09_DEM.tif
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address:
ndewitt@usgs.gov
- Spatial_Data_Organization_Information:
-
- Direct_Spatial_Reference_Method: Raster
- Raster_Object_Information:
-
- Raster_Object_Type: Grid Cell
- Row_Count: 413
- Column_Count: 227
- Vertical_Count: 1
- Spatial_Reference_Information:
-
- Horizontal_Coordinate_System_Definition:
-
- Planar:
-
- Grid_Coordinate_System:
-
- Grid_Coordinate_System_Name: Universal Transverse
Mercator
- Universal_Transverse_Mercator:
-
- UTM_Zone_Number: 16
- Transverse_Mercator:
-
- Scale_Factor_at_Central_Meridian: 0.9996
- Longitude_of_Central_Meridian: -87.0
- Latitude_of_Projection_Origin: 0.0
- False_Easting: 500000.0
- False_Northing: 0.0
- Planar_Coordinate_Information:
-
- Planar_Coordinate_Encoding_Method: row and column
- Coordinate_Representation:
-
- Abscissa_Resolution: 50
- Ordinate_Resolution: 50
- Planar_Distance_Units: meter
- Geodetic_Model:
-
- Horizontal_Datum_Name: D North American 1983
- Ellipsoid_Name: GRS 1980
- Semi-major_Axis: 6378137.0
- Denominator_of_Flattening_Ratio: 298.257222101
- Vertical_Coordinate_System_Definition:
-
- Depth_System_Definition:
-
- Depth_Datum_Name: North American Vertical Datum 88 (NAVD88)
- Depth_Resolution: 0.1
- Depth_Distance_Units: meter
- Depth_Encoding_Method: Implicit coordinate
- Distribution_Information:
-
- Distributor:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: (727) 502-8000
- Contact_Electronic_Mail_Address: ndewitt@usgs.gov
- Resource_Description: Downloadable data
- Distribution_Liability:
- This publication was prepared by an agency of the United States
Government. Although these data were processed successfully on a computer
system at the U.S. Geological Survey, no warranty expressed or implied is
made regarding the display or utility of the data on any other system, nor
shall the act of distribution imply any such warranty. The U.S. Geological
Survey shall not be held liable for improper or incorrect use of the data
described and (or) contained herein. Reference herein to any specific
commercial product, process, or service by trade name, trademark,
manufacturer, or otherwise does not constitute or imply its endorsement,
recommendation, or favoring by the United States Government or any agency
thereof.
- Standard_Order_Process:
-
- Digital_Form:
-
- Digital_Transfer_Information:
-
- Format_Name: GeoTIFF
- File_Decompression_Technique: ZIP
- Transfer_Size: 161 KB
- Digital_Transfer_Option:
-
- Online_Option:
-
- Computer_Contact_Information:
-
- Network_Address:
-
- Network_Resource_Name: https://pubs.usgs.gov/ds/847/data/raster/Chan12_DEM.zip
- Offline_Option:
-
- Offline_Media: DVD-ROM
- Recording_Capacity:
-
- Recording_Density: 4.75
- Recording_Density_Units: GB
- Recording_Format: UDF
- Fees: none
- Technical_Prerequisites:
- The raster contained in the .zip file is available as a GeoTIFF file. To
utilize this data, the user must have a GIS software package capable of
reading .tif format.
- Metadata_Reference_Information:
-
- Metadata_Date: 20131231
- Metadata_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: U.S. Geological Survey
- Contact_Person: Nancy DeWitt
- Contact_Position: Geologist
- Contact_Address:
-
- Address_Type: mailing and physical
- Address: 600 4th Street South
- City: St. Petersburg
- State_or_Province: FL
- Postal_Code: 33701
- Country: USA
- Contact_Voice_Telephone: 727-502-8000
- Contact_Electronic_Mail_Address: ndewitt@usgs.gov
- Metadata_Standard_Name: FGDC Content Standard for Digital
Geospatial Metadata
- Metadata_Standard_Version: FGDC-STD-001-1998
- Metadata_Use_Constraints:
- The U.S. Geological Survey requests that it be referenced as the
originator of this dataset in any future products or research derived from
these data.
- Metadata_Security_Information:
-
- Metadata_Security_Classification_System: None
- Metadata_Security_Classification: Unclassified
- Metadata_Security_Handling_Description: None
Generated by mp
version 2.9.26 on Mon Apr 7 11:11:22 2014