Breton2014_IFB_SBB_100_NAD83_NAVD88_UTM16N_GEOID09_DEM: A geotiff of the
100-meter cell size digital elevation model derived from the processed
interferometric swath, single beam bathymetry, and Lidar data
points.
Metadata:
- Identification_Information:
-
- Citation:
-
- Citation_Information:
-
- Originator: U.S. Geological Survey
- Publication_Date: 2016
- Title:
- Breton2014_IFB_SBB_100_NAD83_NAVD88_UTM16N_GEOID09_DEM: A geotiff of
the 100-meter cell size digital elevation model derived from the
processed interferometric swath, single beam bathymetry, and Lidar data
points.
- Geospatial_Data_Presentation_Form: raster digital data
- Online_Linkage:
- http://pubs.usgs.gov/ds/1005/data/raster/Breton2014_IFB_SBB_100_NAD83_NAVD88_UTM16N_GEOID09_DEM.zip
- Larger_Work_Citation:
-
- Citation_Information:
-
- Originator: Nancy T. DeWitt
- Originator: Jake J. Fredericks
- Originator: James G. Flocks
- Originator: Jennifer L. Miselis
- Originator: Stanley D. Locker
- Originator: Jack G. Kindinger
- Originator: Julie C. Bernier
- Originator: Kyle W. Kelso
- Originator: B.J. Reynolds
- Originator: Dana S. Wiese
- Originator: Trevor Browning
- Publication_Date: 2015
- Title:
- Archive of bathymetry and backscatter data collected in 2014
nearshore Breton and Gosier Islands, Breton National Wildlife
Refuge, Louisiana.
- Geospatial_Data_Presentation_Form: multimedia
presentation
- Series_Information:
-
- Series_Name: U.S. Geological Survey Data Series
- Issue_Identification: 1005
- Publication_Information:
-
- Publication_Place: St. Petersburg, FL
- Publisher: U.S. Geological Survey
- Online_Linkage: http://pubs.usgs.gov/ds/1005
- Description:
-
- Abstract:
- As part of the Barrier Island Monitoring Project, scientists from the
U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science
Center conducted nearshore geophysical surveys off Breton and Gosier
Islands, Louisiana, in July and August of 2014. To assist the United
States Fish and Wildlife Service (USFWS) with restoration planning
efforts, the USGS was tasked with answering fundamental questions about
the physical environment of the southern Chandeleur Islands, including the
geology, morphology, and oceanography. Baseline data needed to answer
these questions was either insufficient or missing in the area. The USGS
conducted a comprehensive geologic investigation in the summer of 2014 by
collecting geophysical and sedimentological data. Breton Island, located
at the southern end of the Chandeleur Island chain, Louisiana, was
recognized as a natural and globally important nesting sanctuary for
several bird species and was established as the Breton National Wildlife
Refuge (NWR) in 1904. The aerial extent of Breton Island has diminished
90% since 1920. Land loss is attributed to ongoing relative sea-level
rise, diminished sediment supply, and storm impacts. The bird population
on Breton Island has also declined over the years, most notably after
Hurricane George in 1998 and Hurricane Katrina in 2015, which completely
submerged the island. Despite the decreasing habitable acreage, migratory
seabirds continue to return and utilize Breton Island. To prevent the
island from being completely submerged in the future and to protect,
stabilize, and provide more nesting and foraging areas for the birding
population, the USFWS is proposing a restoration effort to rebuild Breton
Island to its pre-Katrina footprint. This Data Series serves as an archive
of processed interferometric-swath, single-beam bathymetry, and side-scan
sonar data collected in the nearshore of Breton and Gosier Islands, NWR,
Louisiana. The data were collected during two USGS cruises (USGS Field
Activity Numbers 2014-314-FA and 2014-317-FA) in July and August 2014.
Geographic Information System data products include a 100 meter-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
(FGDC) metadata.
- Purpose:
- This 100-meter cell size digital elevation model is an interpretive
product that was derived from the processed interferometric swath,
single-beam bathymetry, and Lidar data collected in July and August 2014,
around the southern Chandeleur Islands, Louisiana.
- Supplemental_Information:
- The interferometric swath bathymetry navigation data was acquired with
Marinestar High Precision Differential Geographic Positioning System
(DGPS),which used the ITRF2005 datum.
For the single-beam bathymetry,
the differential positioning was obtained through post-processing the base
station data to the rover data. All datasets were transformed from their
initial datums (ITRF00 for SBB and ITRF05 for IFB) to NAD83 using GEOID09
(NOAA NGS VDatum software version 3.2 - http://vdatum.noaa.gov/). The final
x,y,z position data was gridded at a 100-meter cell size resolution to
create the digital elevation model.
- Time_Period_of_Content:
-
- Time_Period_Information:
-
- Single_Date/Time:
-
- Calendar_Date: 2014
- Currentness_Reference: ground condition
- Status:
-
- Progress: Complete
- Maintenance_and_Update_Frequency: none
- Spatial_Domain:
-
- Bounding_Coordinates:
-
- West_Bounding_Coordinate: -89.303995
- East_Bounding_Coordinate: -89.013844
- North_Bounding_Coordinate: 29.598653
- South_Bounding_Coordinate: 29.371525
- 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: 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 Mapping
- Theme_Keyword: Interferometric Bathymetry
- Theme_Keyword: 2014-314-FA
- Theme_Keyword: Digital Elevation Model
- Theme_Keyword: 2014-317-FA
- Theme_Keyword: 14BIM01
- Theme_Keyword: 14BIM02
- Theme_Keyword: 14BIM03
- Theme_Keyword: 14BIM05
- Place:
-
- Place_Keyword_Thesaurus: Geographic Names Information
System (GNIS)
- Place_Keyword: Louisiana
- Place_Keyword: Gulf of Mexico
- Place_Keyword: Chandeleur Islands
- Place_Keyword: Chandeleur Sound
- Place_Keyword: Breton Island
- Place_Keyword: Gosier Islands
- Place_Keyword: Breton Island National Wildlife Refuge
- Stratum:
-
- Stratum_Keyword_Thesaurus: None
- Stratum_Keyword: datum
- Stratum_Keyword: water
- Stratum_Keyword: shoreline
- Temporal:
-
- Temporal_Keyword_Thesaurus: None
- Temporal_Keyword: July 2014
- Temporal_Keyword: August 2014
- 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:
- Funds for this report are part of project funds for the Louisiana Outer
Coast Early Restoration Project, obtained by the natural resource trustees
for the Deepwater Horizon Oil Spill, pursuant to the Framework for Early
Restoration Addressing Injuries Resulting from the Deepwater Horizon Oil
Spill executed April 20, 2011. USFWS is the project lead for the North
Breton Island Barrier Island Restoration project. Acknowledgment of the U.S.
Geological Survey, St. Petersburg Coastal and Marine Science Center, as a
data source would be appreciated in products developed from these data, and
such acknowledgment as is standard for citation and legal practices. Sharing
of new data layers developed directly from these data would also be
appreciated by the U.S. Geological Survey staff. Users should be aware that
comparisons with other datasets for the same area from other time periods
may be inaccurate due to inconsistencies resulting from changes in
photointerpretation, mapping conventions, and digital processes over time.
These data are not legal documents and are not to be used as such.
- Native_Data_Set_Environment:
- Microsoft Windows 7 Service Pack 1; Esri ArcGIS 10.1 Service Pack 1
Build 3143; Esri ArcCatalog 10.1 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 two research cruises, one in July 2014 and the other in August
2014. 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 the critical
measurements are recorded manually and digitally and entered into their
respective programs for calibration. Once calibration is complete and
calibration status is considered acceptable, survey operations commence.
Each system has a dedicated computer, and efforts are made to utilize the
same equipment and software versions on both systems. However, upgrades
and changes occur and require additional setup, measurements, and
notation. For the 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 a
calibration check and accounted for any drift in the echosounder.
Differential Global 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 8.5). 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
Marinestar High Performance wide-area GPS service by Fugro, Inc. 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 interferometric swath and single beam bathymetry data were collected
during two research cruises one in July 2014 and the other in August 2014
(2014-314-FA and 014-317-FA respectively. Refer to the online data series
linkage for field logs, vessel platform descriptions, and other survey
information available at http://pubs.usgs.gov/ds/1005/ds-logs.
The single-beam and interferometric swath bathymetry data were collected
during two research cruises, one in July 2014 and the other in August 2014
(2014-314-FA and 2014-317-FA, respectively).
These datasets were merged
to provide a single post-processed bathymetric digital elevation model (DEM)
at 100-meter cell-size resolution. The data gaps between acquisition
tracklines are predicted values generated by the gridding algorithm. These
bathymetric data have not been independently verified for accuracy.
- Completeness_Report:
- This is a completely processed digital elevation model representing an
interpolated bathymetric surface derived from the acoustic interferometric
single-beam and swath 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 0.00060 seconds latitude and 0.00125 seconds
longitude for the USGS benchmark, BRET, and 0.00023 seconds latitude and
0.00030 seconds longitude for BRT2. The stated horizontal accuracy of
the Marinestar HP navigation subscription used during swath bathymetry
acquisition is reported by the service as +/-15 cm (95% of the time).
- Quantitative_Horizontal_Positional_Accuracy_Assessment:
-
- Horizontal_Positional_Accuracy_Value: -0.00060 to
+0.00060
- Horizontal_Positional_Accuracy_Explanation: latitude
decimal degrees
- Quantitative_Horizontal_Positional_Accuracy_Assessment:
-
- Horizontal_Positional_Accuracy_Value: -0.00125 to
+0.00125
- Horizontal_Positional_Accuracy_Explanation: longitude
decimal degrees
- Vertical_Positional_Accuracy:
-
- Vertical_Positional_Accuracy_Report:
- All static base station sessions for BRET and BRT2 were processed
through 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 three times
the standard deviation of the ellipsoid height; any occupations
exceeding this error are removed and the base station coordinates are
recalculated. For the BRET base station 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 +/- 0.036 m. For the BRT2 base
station location, the standard deviation of the ellipsoid height was
0.012 m and the maximum difference from the average ellipsoid for any
GPS session was +/- 0.029 m. All the processed single-beam bathymetry
data (x,y,z) for 2014 are referenced to these base station coordinates.
The differentially corrected navigation files (base station GPS
processed to boat GPS) were exported from GrafNav version 8.5 and then
imported into CARIS HIPS and SIPS version 8.1.7 and merged, by time,
with the HYPACK (versions 13.0.9.17 and 14.0.9.47) raw data files at
which point the soundings are then geometrically corrected for motion
and speed of sound.
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 centimeters for eastern Louisiana. The sum of the
errors ([+/- 0.013 m] + [+/-0.15 m] +[0.171 m]) in the vertical
direction is equal to +/-.334 m or +/- 33.4 cm.
- Lineage:
-
- Process_Step:
-
- Process_Description:
- GPS Acquisition: A GPS base station was erected at a temporarily
installed USGS benchmark (BRET) located on the sound side of the
Chandeleur Islands. A second base station (BRT2) was temporarily
installed on top of a short piling located approximately 0.40 km
southwest of the BRET base location to provide a backup base station.
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. A similar GPS instrument combination was duplicated on
the survey vessel (rover). The base receivers and the rover receivers
recorded their positions concurrently at the same time intervals
(1.0-second(s) for 14BIM02 and 0.1-s for 14BIM03) throughout the survey.
- Process_Date: 2014
- 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 R/V Jabba Jaw and a 15 ft Personal
Water Craft (PWC) R/V Chum Bucket. Boat motion was recorded at
50-millisecond (ms) intervals using a Teledyne TSS Dynamic Motion Sensor
(TSS DMS-05). HYPACK version 14.0.9.47, 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 using an Odom
echotrac CV100 sounder with 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, with
each device string referenced by a device identification code and time
stamped to UTC.
Sound velocity profile (SVP) measurements were
collected using a SonTek Castaway Conductivity, Temperature, and Depth
(CTD) instrument. The instrument was periodically cast overboard to
observe changes in water column speed of sound (SOS). The recorded
profiles were later incorporated during post-processing to correct the
depth for temporal and spatial SOS changes throughout the water column.
- Process_Date: 2014
- 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 R/V Sallenger in July 2014 and the R/V
Tommy Munro in August 2014, using the SEA SWATHplus-H 468 kHz
interferometric sonar system. The system was fastened to a static pole
mount with the sonar transducer in line with the Novatel GPS antennas
sitting atop the mount. Boat position and motion data were recorded in
real-time using 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 via
Marinestar HP (High-Precision differential global navigation satellite
system) differential subscription service from Fugro, Inc. Marinestar HP
position correction data and motion data from the IMU were integrated
with interferometric soundings in the SWATHplus software version
3.10.2.0 with positional and calibration offsets pre-defined by a
session file (.sxs), allowing for real-time-corrected depths. Before
deployment, all equipment offsets were measured. During the survey, all
swath tracklines were recorded in SWATHplus raw data format (.sxr). A
Valeport Mini Sound Velocity Sensor (miniSVS) was attached to the
transducer mount and collected continuous SOS measurements at the depth
of the transducers. These values were directly read and incorporated
into the SWATHplus raw data format during acquisition providing a
real-time speed of sound measurement at the transducer, while underway.
In addition, a separate Mini Sound Velocity Profiler (Valeport miniSVP)
was used to collect speed of sound profiles (water surface to seafloor)
at intervals throughout the survey.
- Process_Date: 2014
- 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:
- Differentially Corrected Navigation Processing: The coordinate
values of the GPS base station (BRET and BRT2) are the time-weighted
average of values obtained from the National Geodetic Survey On-Line
Positioning User Service (OPUS). The base station coordinates were
imported into GrafNav version 8.5 (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 the trajectories between the base and
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 the respective time intervals of
the roving GPS (1.0 s and 0.10 s) and exported in ASCII text format to
replace the uncorrected rover positions, recorded during acquisition.
The GPS data were processed and exported in the World Geodetic System of
1984 (WGS84)(G1150) geodetic datum.
- Process_Date: 2014
- Source_Produced_Citation_Abbreviation:
- Post-processed differential navigation data for the rover (boat), in
ASCII text format. Three files (forward, reverse, and combined
trajectories) are produced for each GPS session file.
- 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 Processing: All data were processed using
CARIS HIPS and SIPS (Hydrographic Information Processing System and
Sonar Information Processing System) version 8.1.7. The raw HYPACK
(version 13.0.9.17 for 14BIM03 and 14.0.9.47 for 14BIM02) 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 then merged and geometrically corrected in CARIS to produce
processed x,y,z data. Next, the data were edited for outliers and then
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), equivalent to ITRF00; ellipsoid height is presented in meters.
An in house naming convention for the source files used and source files
produced in this process step contain the symbols “xxx” which is a
placeholder for a the naming schema.
- Source_Used_Citation_Abbreviation:
- Post-processed differential navigation data and raw HYPACK
bathymetric data in ASCII text format.
- Process_Date: 2014
- Source_Produced_Citation_Abbreviation:
14BIM02_SBB_ITRF00_03_xxx.txt and 14BIM03_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:
- Swath Bathymetry Processing: The interferometric swath bathymetry
data were collected aboard the R/V Sallenger and the R/V Tommy Munro
using a 468 kHz Systems Engineering and Assessment Ltd. (SEA),
SWATHplus-H (high frequency) interferometric sonar system. SWATHplus
serves as both an acquisition software and initial processing software
package. Preliminary roll calibration trackline data were collected and
processed using SEA SWATHplus version 3.10.2.0 and Grid Processor
software version 3.10.0.0. Instrument offsets and calibration values
were input into the session file (.sxs), and the raw data files (.sxr)
were then 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 and acoustic filtering
utilized in SWATHplus is then applied to each raw data file to create a
processed data file (.sxp), which was then imported into advanced
sounding data processing software CARIS HIPS and SIPS® version 8.1. The
initial real-time processing datum for the swath and backscatter data
was ITRF05, which is the acquisition datum for Marinestar HP position
and navigation data.
All processed data files (.sxp) were imported
into CARIS HIPS and SIPS® version 8.1. Outliers for the navigation data
and processed soundings were removed using program filters. Any
remaining data outliers were then edited 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. A CUBE hypothesis is the
estimated value of a grid node representing all the 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
subset editor. The sample x,y,z data were exported as an ASCII text
file, at a 5-m x 5-m sample resolution in the ellipsoid datum of ITRF05.
The data were then transformed into NAD83 and NAVD88 (GEOID09) using
VDatum version 3.2.
- Process_Date: 2014
- Source_Produced_Citation_Abbreviation:
14BIM01_IFB_04_5m_ITRF05.txt and 14BIM05_IFB_04_5m_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:
- Datum Transformation: Using the transformation software VDatum
version 3.2, the interferometric swath bathymetric data were transformed
horizontally from their data acquisition datum (ITRF05 for the IFB and
ITRF00 for the SBB) to the North American Datum of 1983 (NAD83)
reference frame using the National Geodetic Survey (NGS) geoid model of
2009 (GEOID09). An in-house naming convention for the source files used
and source files produced in this process step contain the symbols “xxx”
which is a placeholder for a the naming schema.
- Source_Used_Citation_Abbreviation:
- 14BIM01_IFB_LEVEL_04_XXX_ITRF05.txt
14BIM02_SBB_Level_03_xxx_ITRF00.txt 14BIM03_SBB_Level_03_xxx_ITRF00.txt
14BIM05_IFB_Level_04_xxx_ITRF05.txt
- Process_Date: 2014
- Source_Produced_Citation_Abbreviation:
- 14BIM01_IFB_04_5m_NAD83_NAVD88_GEOID09.txt
14BIM02_SBB_04_NAD83_NAVD88_GEOID09.txt
14BIM03_SBB_04_NAD83_NAVD88_GEOID09.txt
14BIM05_IFB_04_5m_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: An encompassing digital elevation model
(DEM) was created using the soundings from the individual platforms (R/V
Sallenger--IFB, R/V Tommy Munro--IFB, R/V Jabba Jaw--SBB, and R/V Chum
Bucket--SBB) and lidar data collected in 2014. A running mean of 2 m was
applied to each dataset using the open-source software package, Generic
Mapping Tools (GMT), version 4.5 blockmean filter to avoid aliasing
short wavelengths (Wessel and others 1994). Since the shallow water data
collected by the jet skis overlapped the water depth measurements from
the topobathy lidar survey, the two data files were merged, and a
blockmean filter was applied to the merged data. The data was first
sorted by geographic position so that the blockmean filter would
prioritize by position rather than acquisition platform.
The
resulting data file was then gridded into 100 m grid cells, using the
GMT Tools surface algorithm with a search radius of 200 m to initialize
the grid, and a tension filter of 0.03 to suppress spurious
oscillations. A grid mask generated from a polygon digitized around the
survey area was applied to the resulting grid to exclude areas of "no
data", using the GMT Tools grdmask and grdmath functions. The grid file
in Network Common Data Form (NetCDF) was converted to a raster using
Esri’s ArcMap version 10.2.2 Multidimension Tool "Make NetCDF Raster
Layer" and exported as a GeoTIFF. Additionally, the DEM was converted
into a point file using Esri’s raster to point conversion tool and the
easting and northing positions populated using XTools Pro version 11.1.
The elevation range for the 2014 Breton Island DEM is +1.53 meters to
-10.45 m.
- Source_Used_Citation_Abbreviation:
- The text files below were used to create the final grid file. The
use of "sort" in the file name indicates that the dataset was sorted by
position. The "bm2" identifier indicates that the dataset was sent
through the Generic Mapping Tools (GMT) version 4.5 blockmean filter.
14BIM_jet_lidar_sort_bm2.txt 14BIM01_Sal_ifb_bm2.txt
14BIM02_twin_sbb_bm2.txt 14BIM03_jet_sbb_bm2.txt
14BIM05_Munro_ifb_bm2.txt 14LGC_lidar_bm2.txt
- Process_Date: 2015
- Source_Produced_Citation_Abbreviation:
Breton2014_IFB_SBB_10m_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: 247
- Column_Count: 277
- 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: 100
- Ordinate_Resolution: 100
- 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 1988
(NAVD88)
- Depth_Resolution: 0.001
- 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 have been 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: 12.9
- Digital_Transfer_Option:
-
- Online_Option:
-
- Computer_Contact_Information:
-
- Network_Address:
-
- Network_Resource_Name:
- http://pubs.usgs.gov/ds/1005/data/raster/Breton_2014_IFB_SBB_100_NAD83_NAVD88_UTM16N_GEOID09_DEM.zip
- Fees: none
- Technical_Prerequisites:
- The raster contained in the .zip file is available as a GeoTIFF. To
utilize this data, the user must have a GIS software package capable of
reading the .tif format.
- Metadata_Reference_Information:
-
- Metadata_Date: 2016
- Metadata_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
- 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 2.9.33 on Tue May 17 08:36:11 2016