U.S. Geological Survey
2018
Cape Cod Bay: Polygon boundaries for source data of a continuous bathymetry and topography terrain model of the Massachusetts coastal zone and continental shelf: (Esri polygon shapefile, Geographic, NAD 83).
1.0
Vector Digital Data Set (Polygon)
data release
DOI:10.5066/F72806T7
Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts
U.S. Geological Survey, Coastal and Marine Geology Program
https://doi.org/10.5066/F72806T7
https://www.sciencebase.gov/catalog/item/5a464a15e4b0d05ee8c0548d
Brian D. Andrews
Wayne E. Baldwin
Daniel W. Sampson
William C. Schwab
2018
Continuous bathymetry and elevation models of the Massachusetts coastal zone and continental shelf
1.0
data release
DOI:10.5066/F72806T7
Reston, Virginia
U.S. Geological Survey
Suggested citation: Andrews, B.D., Baldwin, W.E., Sampson, D.W., and Schwab, W.C., 2018, Continuous bathymetry and elevation models of the Massachusetts coastal zone and continental shelf: U.S. Geological Survey data release, https://doi.org/10.5066/F72806T7.
https://doi.org/10.5066/F72806T7
https://www.sciencebase.gov/catalog/item/5a451a3ce4b0d05ee8bedfdc
Integrated terrain models covering 16,357 square kilometers of the Massachusetts coastal zone and offshore waters were built to provide a continuous elevation and bathymetry terrain model for ocean planning purposes. The area is divided into the following four geographical areas to reduce file size and facilitate publishing: Massachusetts Bay from the Massachusetts-New Hampshire border south to Provincetown and Scituate and east to Stellwagen Bank; Cape Cod Bay from Provincetown to Scituate and south to Hyannis; Buzzards Bay from the Cape Cod Canal southwest to the State border including the Elizabeth Islands and extending north to Fall River and Mount Hope Bay; and Nantucket and Vineyard Sounds, from Hyannis south to the border of the Massachusetts Coastal zone approximately 8 kilometers south of Nantucket. A Triangulated Irregular Network was created from public-domain bathymetric and LiDAR data using the ArcGIS terrain-model framework and then interpolated into a 32-bit GeoTiff of 10 meter resolution. The grids for each of the four geographical areas are referenced to the Universal Transverse Mercator, Zone 19, North American Datum of 1983 coordinate system, and the North American Vertical Datum of 1988. A polygon shapefile recording the source datasets accompanies each of the four grids.
The purpose of this polygon feature class is to identify the spatial extent and provenance of the source data used to create the continuous elevation surface. In addition the shapefile will also provide an inventory of the most recent elevation and bathymetry datasets within the Massachusetts coastal zone and offshore water and identify areas of the offshore waters that are only covered by historical lead-line soundings and should be updated by using new survey methods.
This shapefile should be used in conjunction with "CapeCodBay_10m.tif" to understand the collection date, and spatial resolution of the source data are variable and should be considered when using this raster for analysis at fine scales. The attribute table of the “CapeCodBay_Source.shp” provides details about the collection date, and web address of the source data.
1933
2016
ground condition
None planned
-70.838962
-69.756605
42.134424
41.680251
USGS Metadata Identifier
USGS:5a464a15e4b0d05ee8c0548d
none
U.S. Geological Survey
USGS
Massachusetts Office of Coastal Zone Management
CZM
National Ocean Service
NOS
National Oceanic and Atmospheric Administration
NOAA
U.S. Army Corps of Engineers
USACE
shapefile
LiDAR
multibeam
swath bathymetry
fathometer
lead line
ISO 19115 Topic Category
oceans
boundaries
inlandwaters
USGS Thesaurus
bathymetry
sea-floor characteristics
digital elevation models
Geographic Names Information System (GNIS)
United States of America
Commonwealth of Massachusetts
Plymouth County
Barnstable County
Cape Cod
Cape Cod Bay
Plymouth Bay
Green Harbor
Gurnet Point
Manomet Point
Cape Cod Canal
Sandy Neck
Barnstable Harbor
Billingsgate Shoal
Chatham Harbor
Race Point
Provincetown
none
1933
1934
1940
1954
1955
1968
1971
1998
2003
2005
2006
2007
2010
2011
2013
2015
2016
None.
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information. Users are advised to read the data set's metadata thoroughly to understand appropriate use and data limitations.
Brian Andrews
U.S. Geological Survey
Geographer
mailing and physical address
384 Woods Hole Rd.
Woods Hole
MA
02543-1598
USA
508-548-8700 x2348
508-457-2310
bandrews@usgs.gov
https://www.sciencebase.gov/catalog/file/get/5a464a15e4b0d05ee8c0548d?name=CapeCodBay_Source.jpg
Image of source data boundaries for the terrain model of Cape Cod Bay and surrounding elevations of the Massachusetts Coastal Zone. File is located in the compressed zip file.
JPEG
Please recognize the U.S. Geological Survey (USGS) as the source of this information.
Version 6.2 (Build 9200) ; Esri ArcGIS 10.3.1.4959
No formal attribute accuracy tests were conducted.
Polygon boundaries were created to outline the spatial extents of each input data source for the terrain model. The boundaries for the LiDAR and multibeam data were created by converting the boundary of the raster data to a polygon. The boundaries for the historical NOS sounding data were created by digitizing a boundary polygon around the extent for each of the datasets such that adjacent polygons do not overlap. The perimeter boundary of all four polygon datasets published in this data release were designed to overlap in order to create a seamless surface if the resulting GeoTIFFs are mosaicked together. General guidelines were established for the selection of the source elevation data, but for such a large area and complicated series of possible input datasets, the same source dataset may not have been chosen – therefore areas of overlap of the four individual datasets (BuzzBay_Source, CapeCodBay_Source , MassBay_Source, and Ntk_VS_Source) may not indicate the same source dataset.
The individual polygons only delineate the extent of data used to compile the terrain model and may not include all the data collected during the individual survey. Gaps exist between adjacent polygons.
This polygon shapefile was generated by a combination of digitizing around actual sounding data, and converting rasters to polygons. Each feature in the shapefile encompasses the extent of each input dataset. The horizontal accuracy is dependant on the accuracy of the input dataset, and the scale used to digitize/edit the polygon features.
PROCESS STEP 1: CREATE EMPTY POLYGON FEATURE CLASS TO STORE THE OUTLINES OF ALL THE SOURCE DATA.
Create an empty polygon feature class within a file geodatabase using the context menu in ArcCatalog (v. 10.3.1). Projection is set to UTM Zone 19 NAD 83. Add the following fields to the new feature class using the "add field" menu in the attribute table view: Source, SurvYear, PubLink, SourceType. All processing steps were completed by Brian Andrews.
201606
CapeCodBay_Source (feature class)
Brian Andrews
U.S. Geological Survey
Geographer
mailing and physical address
384 Woods Hole Rd
Woods Hole
MA
02543-1598
USA
508-548-8700 x2348
508-457-2310
bandrews@usgs.gov
PROCESS STEP 2: CREATE POLYGON BOUNDARY FILES FOR ALL LiDAR DATA.
An 8-bit integer raster was created for each source LiDAR GeoTIFF listed in "Step 2" of the CapeCodBay_10m.tif metadata using the grid query "Value less than 1000." The resulting integer raster was converted to polygon using the Raster to Polygon tool in ArcGIS (v. 10.3.1).
201607
"SurveyName"_Mask
PROCESS STEP 3: CREATE BOUNDARY FILES FOR SWATH AND MULITBEAM DATA.
An 8-bit integer raster was created for each source swath bathymetry grid listed in "Step 3 and 4" of the CapeCodBay_10m.tif metadata using the grid query "Value less than 0." The resulting integer raster was converted to polygon using the Raster to Polygon tool in ArcGIS (v. 10.3.1)
201607
"SurveyName"_Mask
PROCESS STEP 4: CREATE BOUNDARY FILES FOR ALL HISTORICAL NOS SOUNDING DATA.
Create an empty polygon feature class for each of the historical NOS surveys using the context menu in ArcCatalog (v. 10.3.1). Projection is set to UTM Zone 19, NAD 83 (2011). Edit each of the polygons and digitize a boundary that encompasses all the input soundings.
201607
"SurveyName"_Mask
PROCESS STEP 5: CLIP AND MERGE THE SOURCE POLYGONS INTO ONE FEATURE CLASS.
This process was completed in three basic steps based on a data hierarchy using both qualitative and quantitative comparison between datasets in any areas of overlap. Starting with the LiDAR data, the individual polygons for each of the LiDAR surveys were compared for areas of overlap. In areas of overlap the newest LiDAR data with highest quality was generally used to clip (remove) overlapping older data used to create the terrain model. Qualitative criteria for determining which data to keep in areas of overlap included data density, data collection date, and data quality (are survey line artefacts visible). For example, along the south shore of Cape Cod, overlap exists between the 2007 and 2010 Army Corps of Engineers surveys. The full extent of the 2010 survey was used to clip (remove), the areas from the 2007 polygon because the 2010 data were more recent. The resulting clipped polygons were used later to extract the desired data for export as multipoint feature classes into the feature dataset used to create the terrain model. The vertical difference between overlapping raster data (LiDAR, swath, or multibeam) was used as a quantitative criteria for determining which data to retain in areas of overlap. Once these comparisons were conducted the polygons were clipped, then appended to the "MassBay_Source" feature class created in Step 1 above.
Second, the polygons for swath and multibeam created in Step 3 above were clipped and appended to the "CapeCodBay_Source" feature class in a similar manner as the LiDAR polygons. Polygon masks of newer multibeam data were used to clip older survey data in the areas of overlap. The final polygons representing swath and multibeam data were used later to extract the desired depth data for export as a multipoint feature class to create the terrain model. Each source survey was exported as a separate multipoint, or simple point, feature class to facilitate data management.
Finally, the polygons for each of the historical NOS surveys from Step 4 above were compared in areas of overlap with newer multibeam or LiDAR data and clipped to remove older historical sounding data. During the clip process, an additional buffer of 50 to 100 meters was applied using the "Buffer Distance" in the ArcGIS Clip Tool under the Edit Menu. This 50-100 meter gap created a smoother transition during the gridding process between high resolution data (LiDAR and multibeam) and low resolution data (historical NOS soundings). These edited polygons were then used to extract the desired sounding data for export as point feature class into the Terrain Model feature data set. The final polygons for each survey were appended to the "CapeCodBay_Source" feature class.
"SurveyName"_Mask
201607
CapeCodBay_Source
PROCESS STEP 6: EXPORT FEATURE CLASS TO SHAPEFILE:
Finally, exported the CapeCodBay_Source feature class into a Esri Shapefile using the context menu in ArcCatalog (v. 10.3.1). The projection of the output shapefile was set to Geographic NAD 83 during the export process.
CapeCodBay_Source feature class
201607
CapeCodBay_Source.shp
Added keywords section with USGS persistent identifier as theme keyword.
20200807
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Vector
GT-polygon composed of chains
34
0.000001
0.000001
Decimal degrees
D_North_American_1983
GRS 1980
6378137.0
298.257222101
CapeCodBay_Source
Table containing attribute information associated with the data set.
USGS
FID
Internal feature number.
Esri
0
33
Shape
Feature geometry.
Esri
Coordinates defining the features.
Source
Simplified name of the survey used as input data using either the agency acronym, and date, or in just the survey ID (NOAA).
USGS
character set
SurvYear
The year the survey was conducted, in some cases, the source grid included data collected during several years. In these cases, the SurvYear is the first year of the multiple surveys which are documented in the metadata for the"CapeCodBay_10m.tif"
USGS
1933
2016
Year
PubLink
URL to published data files and metadata for each survey. For LiDAR datasets, this is the url where the laz files were downloaded.
USGS
character set
SourceType
Sensor or method used to collect the data
Producer defined
Lead Line
Hand-deployed sounding device that is usally positioned with visual bearings to know objects ashore. These data, collected in the 1930', are the oldest sounding and of lowest quality.
NOS
Fathometer
refers to a digital sounding device recorded on paper used in the 1940's. Navigation for these surveys used three-point triangulation from visual observations to objects ashore.
NOS
LiDAR
LIght Detection and Range
USGS
Multibeam
Multibeam Sonar
USGS
Swath
Interferometric Sonar
USGS
Shape_Leng
Length of the polygon feature in meters calculated in the feature class using UTM Zone 19 meters NAD 83, before it was exported as shapefile.
Esri
4415.975
1793836.69113
meters
Shape_Area
Area of feature in meters squared calculated in the feature class using UTM Zone 19 meters NAD 83, before exporting to shapefile.
Esri
205481.5477
566277137.820454
meters squared
U.S. Geological Survey-ScienceBase
mailing and physical address
Denver Federal Center, Building 810, Mail Stop 302
Denver
CO
80225
USA
1-888-275-8747
sciencebase@usgs.gov
CapeCodBay_Source.zip: file contains the polygon feature class (CapeCodBay_Source.shp), CapeCodBay_Source.jpg browse graphic, and the associated FGDC CSDGM metadata in XML, HTML, FAQ, and text formats.
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.
shapefile
ArcGIS (v. 10.3.1)
Esri polygon shapefile
This WinZip file contains a polygon shapefile, and associated metadata for source data used to produce the terrain model of Cape Cod Bay.
WinZip
5.6
https://www.sciencebase.gov/catalog/file/get/5a464a15e4b0d05ee8c0548d?name=CapeCodBay_Source.zip
https://www.sciencebase.gov/catalog/item/5a464a15e4b0d05ee8c0548d
None
To utilize this data, the user must have software capable of reading an Esri shapefile.
20200807
Brian Andrews
U.S. Geological Survey, Northeast Region
Geographer
mailing address
384 Woods Hole Road
Woods Hole
MA
02543
508-548-8700 ext. 2348
bandrews@usgs.gov
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time