Short Citation:
Office for Coastal Management, 2021: Hudson River Sub_Bottom Profile Data - Raw SEG-Y Files (*.sgy), https://www.fisheries.noaa.gov/inport/item/47919.

Item Identification

Title: Hudson River Sub_Bottom Profile Data - Raw SEG-Y Files (*.sgy)
Short Name: ny_hr09_sbp-segy-meta
Status: Completed
Publication Date: 2010
Abstract:

Hudson River Estuary Shallow Water Surveys. Subbottom data was collected November 5 to December 15, 2009, in the estuary north from Saugerties to Troy. Data Collection and Processing: Subbottom Data - Fugro utilized the EdgeTech SB216 Chirp subbottom profiler system for seismic data collection. This system was operated using a swept frequency range of 2-16 KHz, maximizing subsurface resolution within the very shallow near-surface material (1- 5 m beneath seafloor). Subbottom data was processed and interpreted using Discover and SMT Kingdom software. The intent of the processing was to provide the NYSDEC with SEG-Y files that were properly filtered and spatially oriented to allow for near-surface interpretation of sediments in the Hudson River. Processing steps for the subbottom data included swell filtering to compensate for sea conditions during survey operations, compiling correct shotpoint navigation, and adjusting data gains for optimal interpretation. An isopach (sediment thickness) of the unconsolidated surficial sediments was created from the seafloor and mapped sediment horizon base using an acoustic two-way travel time of 1500 meters/second. Subbottom data was used to assist in selecting sediment sampling locations. Graphical sub-bottom profiles for areas of interest were produced and descriptive results will be included in the final report. Points were created every 300th shot (approximately 100 meters).

Original contact information:

Contact Name: John Ladd

Contact Org: Hudson River National Estuarine Research Reserve, NYS DEC

Phone: 845-889-4745

Email: jxLadd@gw.dec.state.ny.us

Purpose:

Our work was consistent with the Statement of Work prepared by the New York State Department of Environmental Conservation (NYSDEC) to develop detailed bathymetric maps, acoustic reflectivity and acoustic character maps of the shallow portions of the Hudson River Estuary from the Verrazano Narrows north to the federal dam in Troy. In addition NYSDEC requested the collection of grab samples and 100 sediment cores at least one meter in length distributed throughout the same shallow portions of the Estuary. This project was being conducted as part of the Hudson River Estuary Action Plan promulgated by NYSDEC and approved by the Governor in 1996 which committed the State to, among other things, -Conduct a submerged habitat inventory to define areas most in need of protection for Hudson River fish, blue crab, and food chain species. -To conserve, protect, and, where possible, enhance critical river and shoreline habitats to assure that the life cycles of key species are supported for human enjoyment and to sustain a healthy ecosystem. -To conserve for future generations the rich diversity of plants, animals and habitats that are key to the vitality, natural beauty and environmental quality of the Hudson River Valley. Previous work in the Estuary was limited, in that detailed bathymetry was not acquired in areas of the estuary shallower than about 4 meters due to financial constraints. About a third of the estuary was not surveyed this third is the area that is home to important submerged aquatic vegetation (SAV) beds which sustain much of the biologic community in the estuary. Utilizing advanced technology and the experience of the previous benthic mapping projects, this project provided NYSDEC maps of the shallow areas that were not addressed with the previous studies. Pilot studies (Maher, 2006; Strayer et al., 2006; Yeung and McConnaughey 2008) have indicated that variations in remote sensing acoustic data are strongly correlated to variations in benthic macro invertebrate communities. This primary goal of this project, guided by NYSDEC, was to acquire acoustic data in the shallow water areas of the estuary that would facilitate classification of the substrate into biologically significant units.

Notes:

10076

Supplemental Information:

Geographic limits of the project survey covered some or all shallow areas of the estuary from the Verrazano Narrow Bridge north to the federal dam at Troy. The landward limit of surveys along the eastern shore of the estuary was the low tide line or the railroad tracks that extend up the east shore of the estuary whichever was most westward on a given line of latitude including Schodack Creek north to Little Schodack Island. The landward limit of surveys along the western shore was the low tide line or the railroad tracks that extend up the west shore of the estuary whichever is most eastward on a given line of latitude except for tidal portions of tributaries such as the Binnen Kill north of Interstate 90 and Catskill Creek north of Bridge Street. For the purposes of this project the low-tide line was the line of zero depth relative to mean lower low water (MLLW) depicted on NOAA charts 12347 and 12348. The EdgeTech FS-SB subbottom profiler deployed during survey operations operated at a swept frequency range of 2-16 kHz. However, a transducer ping rate of 6-8 Hz (depending on water depths) corresponded to a hardware-applied data sampling interval of 40 microseconds. A built in anti-alias filter ensured a recorded frequency cut-off of 12 kHz. This is the maximum frequency that can be sampled at 40 microseconds, ensuring that no higher frequency events (above 12kHz) are aliased as a lower frequency event in the data. Given that high frequency events tend to rapidly attenuate in the water column and immediate subsurface, the lack of recorded frequencies above 12 kHz does not adversely impact data resolution (.02 meters estimated resolution for 16 kHz and .03 meters for 12 kHz) or subsurface mapping capabilities given the system's stated overall resolution (incorporating lower frequencies toward 2 kHz) of .1 meter.

Keywords

Theme Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Science Keywords Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Benthic
Global Change Master Directory (GCMD) Science Keywords Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Coastal
Global Change Master Directory (GCMD) Science Keywords Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Estuary
ISO 19115 Topic Category environment
None Environment Monitoring
None Subbottom, Profile, Chirp, Shallow Water, River

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords Continent > North America > United States Of America > New York
None Hudson River
None New York
None USA

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: None Planned
Data Presentation Form: Map (digital)
Entity Attribute Overview:

Sub bottom profile trace header data in SEG-Y format

Entity Attribute Detail Citation:

Fugro

Distribution Liability:

NOAA manages much of the data to users of digital geographic data.NOAA is in no way condoning or endorsing the application of this data for any given purpose.It is the sole responsibility of the user to determine whether or not the data is suitable for the intended purpose.It is also the obligation of the user to apply the data in an appropriate and conscientious manner.NOAA provides no warranty,nor accepts any liability occurring from any incomplete,incorrect, or misleading data, or from any incorrect,incomplete, or misleading use of the data.Much of the data is based on and maintained with ARC/GIS software developed by the Environmental Systems Research Institute (ESRI).In addition, much of the information presented uses conventions and terms popularized by ARC/GIS and its user community. NOAA in no way represents the interests of ESRI,nor acts as agents for them.

Data Set Credit: Patrick Nissen, Robbie Dame, Jeff Carothers, Gilbert Suarez, Cindy Pratt, Fugro

Support Roles

Data Steward

CC ID: 612787
Date Effective From: 2010
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address: coastal.info@noaa.gov
Phone: (843) 740-1202
URL: https://coast.noaa.gov

Distributor

CC ID: 612789
Date Effective From: 2010
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address: coastal.info@noaa.gov
Phone: (843) 740-1202
URL: https://coast.noaa.gov

Metadata Contact

CC ID: 612790
Date Effective From: 2010
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address: coastal.info@noaa.gov
Phone: (843) 740-1202
URL: https://coast.noaa.gov

Point of Contact

CC ID: 612788
Date Effective From: 2010
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address: coastal.info@noaa.gov
Phone: (843) 740-1202
URL: https://coast.noaa.gov

Extents

Currentness Reference: Publication Date

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 612793
W° Bound: -73.933423
E° Bound: -73.685289
N° Bound: 42.752039
S° Bound: 42.06449

Extent Group 1 / Time Frame 1

CC ID: 612792
Time Frame Type: Discrete
Start: 2009

Spatial Information

Spatial Representation

Representations Used

Grid: Yes

Access Information

Security Class: Unclassified
Data Access Constraints:

None

Data Use Constraints:

None

Distribution Information

Distribution 1

CC ID: 750574
Download URL: ftp://ftp.coast.noaa.gov/pub/benthic/Sub-Bottom_Profile_Data/NY_HudsonRiver_sbp.zip
Distributor:
File Name: Bulk Download
Description:

FTP download of data files.

Activity Log

Activity Log 1

CC ID: 612805
Activity Date/Time: 2017-03-30
Description:

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 612804
Activity Date/Time: 2017-11-14
Description:

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using 'fgdc_to_inport_xml.pl' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 717929
Activity Date/Time: 2018-02-08
Description:

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 750575
Activity Date/Time: 2018-04-11
Description:

Partial upload to move data access FTP links to Distribution Info and remove broken URLs.

Technical Environment

Description:

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.3.0.1770

Data Quality

Horizontal Positional Accuracy:

Data are geo-referenced using differential GPS (DGPS) which results in a lateral accuracy of <+/-1 meter.

Completeness Report:

The data covers the area of the estuary north from Saugerties to Troy in areas of shallow water (defined as any part of the estuary covered by water at low tide and shallower than 5 meters relative to NAVD88. For the purposes of this project the low-tide line was the line of zero depth relative to mean lower low water (MLLW) depicted on NOAA charts 12347 and 12348.

Conceptual Consistency:

Fugro utilized the EdgeTech SB216 Chirp subbottom profiler system for seismic data collection. This system was operated using a swept frequency range of 2-16 KHz, maximizing subsurface resolution within the very shallow near-surface material (1- 5 m beneath seafloor). Position of the device was determined every second. After acquisition, navigation data was examined for outliers and applied to the subbottom profiler data to ensure proper positioning in the spatial domain.

Lineage

Process Steps

Process Step 1

CC ID: 612781
Description:

The position recorded in the header of the SEG-Y file comes from the GPS navigation system interfaced to the sub bottom profiler computer, whereas the time comes from the sub bottom profiler computer clock. It has been determined that the time of the sub bottom profiler PC clock was offset from GPS time (as collected by the side scan sonar system). The positions found in the SEG-Y file headers and the SBP_points attribute tables represent the position of the subbottom profiler source at the GPS times for that position as found in the XTF headers and the Sidescan Sonar ping shape file attribute table. Users should not use time but rather geographic positions to compare the sub bottom profile and side scan sonar datasets. Subbottom data was processed and interpreted using Discover and SMT Kingdom software. The intent of the processing was to provide the NYSDEC with SEG-Y files that were properly filtered and spatially oriented to allow for near-surface interpretation of sediments in the Hudson River. Processing steps for the subbottom data included swell filtering to compensate for sea conditions during survey operations, compiling correct shotpoint navigation, and adjusting data gains for optimal interpretation. Ship GPS data were acquired using a Trimble AG332 GPS receiver, operating at 1 Hz. The GPS position of the sub bottom fish was calculated in the Discover software on the XStar topside processor by applying a layback (the offset of the towfish from the GPS antenna). The raw GPS data were viewed in ArcGIS for any outliers, and the processed data were applied to the SEG-Y files in Kingdom. Final corrected positions are accurate to <+/- 1 meter.

Process Date/Time: 2010-01-01 00:00:00

Process Step 2

CC ID: 612782
Description:

The position recorded in the header of the SEG-Y file comes from the GPS navigation system interfaced to the sub bottom profiler computer, whereas the time comes from the sub bottom profiler computer clock. It has been determined that the time of the sub bottom profiler PC clock was offset from GPS time (as collected by the side scan sonar system). The positions found in the SEG-Y file headers and the SBP_points attribute tables represent the position of the subbottom profiler source at the GPS times for that position as found in the XTF headers and the Sidescan Sonar ping shape file attribute table. Users should not use time but rather geographic positions to compare the sub bottom profile and side scan sonar datasets. Subbottom data was processed and interpreted using Discover and SMT Kingdom software. The intent of the processing was to provide the NYSDEC with SEG-Y files that were properly filtered and spatially oriented to allow for near-surface interpretation of sediments in the Hudson River. Processing steps for the subbottom data included swell filtering to compensate for sea conditions during survey operations, compiling correct shotpoint navigation, and adjusting data gains for optimal interpretation. Ship GPS data were acquired using a Trimble AG332 GPS receiver, operating at 1 Hz. The GPS position of the sub bottom fish was calculated in the Discover software on the XStar topside processor by applying a layback (the offset of the towfish from the GPS antenna). The raw GPS data were viewed in ArcGIS for any outliers, and the processed data were applied to the SEG-Y files in Kingdom. Final corrected positions are accurate to <+/- 1 meter.

Process Date/Time: 2010-01-01 00:00:00

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity (ENT) SEG-Y headers

Catalog Details

Catalog Item ID: 47919
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-14 12:57+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2019-07-02 15:17+0000
Metadata Record Published: 2018-04-11
Owner Org: OCM
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2019-04-12