The geophysical mapping utilized a suite of high-resolution instrumentation to map the surficial sediment distribution, depth and sub-surface geology: dual-frequency 100/500 KHz sidescan-sonar system, 234-KHz interferometric sonar, and 500 Hz -12 KHz chirp sub-bottom profiler. The survey was conducted aboard the M/V Megan Miller August 9-13, 2007. The study area covers 35 square kilometers from about 0.2 km to 5-km offshore of the south shore of Martha's Vineyard, and ranges in depth from ~ 5 to 20 meters.
U.S. Geological Survey, 2009, SVP: Location of sound velocity profiles collected by the U.S. Geological Survey off the southern shore of Martha's Vineyard, MA, 2007 (ESRI POINT SHAPEFILE): Open-File Report 2008-1288, U.S. Geological Survey, Woods Hole.This is part of the following larger work.Online Links:
- <https://pubs.usgs.gov/of/2008/1288/GIS_catalog/Bathy/svp.zip>
- <https://pubs.usgs.gov/of/2008/1288/html/gis.html>
Denny, J.F., Danforth, W.W., Foster, D.S., and Sherwood, C.R., 2009, Geophysical Data Collected off the South Shore of Martha's Vineyard, Massachusetts: Open-File Report 2008-1288, U.S. Geological Survey, Woods Hole.Online Links:
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees.
The horizontal datum used is D_WGS_1984.
The ellipsoid used is WGS_1984.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257224.
Sequential unique whole numbers that are automatically generated.
Coordinates defining the features.
Range of values | |
---|---|
Minimum: | 364504 |
Maximum: | 373503 |
Units: | meters |
Range of values | |
---|---|
Minimum: | 4573848 |
Maximum: | 4577889 |
Units: | meters |
Range of values | |
---|---|
Minimum: | 1 |
Maximum: | 13 |
Units: | incremental svp station identification |
Range of values | |
---|---|
Minimum: | 8.5 |
Maximum: | 22 |
Units: | meters |
Range of values | |
---|---|
Minimum: | 0 |
Maximum: | 23 |
Units: | hour |
Range of values | |
---|---|
Minimum: | 0 |
Maximum: | 60 |
Units: | minute |
Range of values | |
---|---|
Minimum: | 0 |
Maximum: | 60 |
Units: | second |
Range of values | |
---|---|
Minimum: | 221 |
Maximum: | 225 |
Units: | Julian Day |
JPG image file depicting SVP profile for given station
Range of values | |
---|---|
Minimum: | -70.618758 |
Maximum: | -70.511816 |
Units: | Decimal Degrees |
Range of values | |
---|---|
Minimum: | 41.305003 |
Maximum: | 41.342546 |
Units: | Decimal Degrees |
U.S. Geological Survey
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
This dataset is used to display the location of sound velocity profiles collected during USGS Cruise 07011 off the southern shore of Martha's Vineyard, 2007. The information contained within the sound velocity profiles is needed to adequately account for refraction artifacts that may be present within raw swath bathymetric data. This dataset contains hyperlinks to graphs of the sound velocity profile within the water column at each station location, as well as location in easting and northing (UTM, Zone 19N, WGS84, meters), latitude, longitude, time of day and date.
.
Swath bathymetric data were collected using an SEA Ltd SWATHplus 234-kHz Interferometric Bathymetric Sonar (<http://www.sea.co.uk/swathplus.aspx?nav=products> ) during survey operations. The SWATHplus system was mounted as a sidemount and positioned on the starboard side of the R/V Megan Miller. Line spacing varied from 40 meter in ~ 5 to 15 meter water depth to 70 meters in ~15 - 25 meter water depth. Data files were recorded by SEA software SWATHplus 3.05.19 in the SWATHplus SXR format. Data collection parameters are saved into a SWATHplus session file in SEA's SXS format that can be later used for data replay.
Pitch, roll, heading, and heave information were recorded using a Coda Octopus F180R motion reference unit (MRU) (see: <http://www.codaoctopus.com/motion/f180/index.asp>) and transmitted via network connection to the SWATHplus data collection software. The MRU sensor was mounted directly above the SWATHplus transducers, thereby minimizing "lever arm" offsets which can lead to positioning and depth errors in the bathymetric data. The F180R series MRU uses two L1 antennas for position and heading accuracy. These were mounted directly above the MRU with an offset of 6.76 meters. The antennas are mounted on a rigid horizontal pole with a separation of 1 meter and are offset from the MRU in a forward/aft configuration. The forward offset of the primary antenna from the MRU is 0.5 meters, with no port/starboard offset.
Sound Velocity Profiles (SVP): Fourteen sound velocity casts were collected at various intervals during the USGS cruise 07011 using an Applied Microsystems SV Plus v2 instrument (see <http://www.appliedmicrosystems.com/products/productDetails.aspx?id=1> for details). Sound velocity profiles (SVP) were generally collected at the eastern and western ends of the survey area, corresponding to the start and/or end of geophysical line data collection. This procedure was primarily followed to coordinate collection of SVP casts with the beginning or end of trackline. This was acceptable because only small variations in the speed of sound were noted throughout the survey area and negligible refraction artifacts were visible within the swath bathymetric data.
At each pre-defined station (i.e. location), the SV plus v2 was slowly lowered to the seafloor using a small shipboard winch. The SV plus v2 was monitored by a member of the science party and as the instrument made contact with the seafloor, the position (i.e. location) was recorded in the lab using HYPACK navigation software. The position was then manually recorded within the cruise log and SWATHplus acquisition software. Upon recovery, the SV plus was connected to an onboard computer via serial port in order to download data using the SV plus v2 communications software, SmartTalk.
Software: SV plus v2 SmartTalk (no version)
Person who carried out this activity:
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
Software: Microsoft Excel 2004; Adobe Photoshop CS3 (10.0.1)
Person who carried out this activity:
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
Software: AWK (no version)
Person who carried out this activity:
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
Software: ArcGIS 9.2
Person who carried out this activity:
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
Software: ArcGIS 9.2
Person who carried out this activity:
508-548-8700 x 2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
Software: ArcGIS 9.2
Person who carried out this activity:
508-458-8700 x 2311 (voice)
508-457-2310 (FAX)
jdenny@usgs.gov
Real-Time Kinematic (RTK) navigation data were collected using an Ashtech Z-Extreme receiver, mounted on the SWATHplus sidemount and recorded using navigation software from HYPACK, Inc (<http://www.hypack.com/new/>). RTK provides accuracies on the order of 10s of centimeters (<http://www.navcen.uscg.gov/>). However, the horizontal and vertical offsets between the hand-winch used to deploy the SV plus v2 sound velocity profiler and the RTK antenna on the SWATHplus sidemount were not accounted for in determining the location of the sound velocity profiler. Thus, the horizontal accuracy of the sound velocity locations is considered to be +/- 10 meters.
Water depth of the sound velocity profile locations were acquired by reading the depth from the SWATHplus acquisition system. Precise depths are recorded within the sound velocity profile as it is lowered and recovered through the water column.
Vertical and horizontal position of the SWATHplus system were acquired with Differential Global Positioning System (DGPS) navigation. DGPS data were acquired with the forward, or primary, Coda Octopus F180R Motion Reference Unit (MRU) DGPS antenna and transmitted via a network connection to the SWATHplus data collection software. The F180R MRU is part of the rigid sidemount used to deploy the SWATHplus bathymetric system, and is mounted on the bracket holding the SWATHplus transducers. The F180R MRU consists of 2 L1 antennas used for position and heading. The antennas are mounted on a rigid horizontal pole, 6.76 meters above the F180R MRU, offset in a forward/aft configuration (see 'source contribution' for a full description of the F180R). DGPS accuracy is 1 to 3 meters, depending on the distance from a US Coast Guard coastal repeater station (<http://www.navcen.uscg.gov/>). However, offsets between the winch used to deploy the sound velocity profiler and the DGPS antenna were not recorded. Therefore, water depths provided are intended to give a general depth at the sound velocity profile location (within 1 meter).
All sound velocity profiles collected during USGS Cruise 07011 are included in this ESRI shapefile.
All sound velocity profiles were acquired with the same instrument during the course of USGS Cruise 07011; an Applied Microsystems SV plus v2.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
Downloadable Data
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.
Data format: | WinZip file containing ESRI point shapefile and associated metadata for sound velocity profiles collected during USGS Open-File Report 2008-1288 in format WinZip (version 9.0) Size: 36 KB |
---|---|
Network links: |
<https://pubs.usgs.gov/of/2008/1288/GIS_catalog/Bathy/svp.zip> |
This zip file contains data available in Environmental Systems Research Institute (ESRI) point shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from ESRI at www.esri.com.
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov