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, HYPACK NAVIGATION: Text files of the Real-time Kinematic (RTK) navigation logged with HYPACK Software during USGS Cruise 07011 conducted off the southern shore of Martha's Vineyard, 2007.: 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/Nav/hypack.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 Point data set.
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.
FTP: The first record located at the top of the header used to identify the file format.
VER: HYPACK version number.
INF: General survey information filled in by the data technician.
FIL: Raw format file.
ELL: Ellipsoid information. The name of the ellipsoid followed by the semi-major axis in meters and the flattening ration.
PRO: Project information record where TME indicates Transverse Mercator and the central meridian of -69 indicates UTM, zone 19.
DTM: Datum transformation record
GEO: Geoid model. Blank if not present.
HVU: Horizontal and Vertical Units (meters)
TND: Survey time and date in UTC.
DEV 0: Indicated that the lines collected with device designation 0 are lines of single-beam echo sounder.
OFF: device offsets (none used during this data collection)
DEV 1: Indicates that lines collected with device designation 1 are using Ashtech Z-Extreme, capable of recording antenna elevations above a vertical datum (i.e. real-time kinematic, RTK)
OFF: device offsets (non used during data collection)
LIN 2: planned line data follows
PTS: planned line waypoints (eastings and northings, UTM, zone 19N, meters)
LBP: planned line begin point (easting and northings, UTM zone 19N, meters)
LNN 1: planned line name
EOL: end of planned line
EOH: end of header
The remaining elements have similar information in the first 3 columns. The first column will indicate the data type, the second column will indicate the device that recorded the information (e.g. 1 for Ashtech receiver) and the third column is the time tag (seconds past midnight) that is also sometimes referred to as the latency. The remaining information on each line is specific to the data type.
MSG: Message string in the format "MSG dn t message" where dn=device number; t=time tag (seconds past midnight); message is the message sent from the device.
EC1: echo sounding (singe frequency). Format "EC1 dn t rd", where dn=device number, t=time tag (seconds past midnight), rd=raw depth.
POS: Position of the ship in the format "POS dn t x y" where dn=device number; t=time tag (seconds past midnight); x=easting; y=northing. On this cruise these values are in UTM, Zone 19, WGS84.
QUA: Position quality information in the format "QUA dn t n m h sat mode" where dn=device number; t=time tag (seconds past midnight); n=number of values to follow; m = 10 minus HDOP (horizontal dilution of precision); h=HDOP; sat=number of satellites; mode=GPS mode (NMEA 0183 standard values) where 0=fix not available or invalid; 1=GPS fix; 2=Differential GPS fix; 3=GPS PPS Mode fix; 4=RTK fix; 5=RTK float.
RAW: Position information in the format "RAW dn t n lat long alt utc" where dn=device number; t=time tag (seconds past midnight); n=number of values to follow; lat=raw latitude X 100; long=raw longitude X 100; alt=antenna altitude above ellipsoid (meters); utc=GPS time in the format HHMM.
TID: Tide correction. Format "dn t dc", where dn=device number, t=time tag (seconds past midnight), dc = draft correction.
FIX: Fix (event) mark. Format "FIX vn", where n=FIX format version number, Always 2nd record in file.
The (National Marine Electronics Association) NMEA strings $GPGGA, $GPVTG, and $GPZDA are stored in the HYPACK file. These are defined as follows.
$GPGGA is GPS fix data in the format "$GPGGA, t, lat, lath, long, longh, q, sat, h, a, M, alt, M, t2, refcheck" where t=time in UTC in the format hhmmss.ss; lat=latitude in the format ddmm.mmmmmm; lath= N or S indicating the latitude hemisphere; long=longitude in the format dddmm.mmmmmm; longh=E or W indicating the hemisphere; q=fix quality where 0=fix not available or invalid; 1=GPS fix; 2=Differential GPS fix; 3=GPS PPS Mode fix; 4=RTK fix; 5=RTK float; sat=number of satellites; h=Horizontal Dilution of Precision (HDOP); a=Antenna altitude above mean sea level (geoid); M= units of antenna altitude in meters; alt=height of geoid above WGS84 ellipsoid; M=units of geoidal height in meters; t2=time since last DGPS update; refcheck=DGPS reference station id and the checksum.
Example: $GPGGA,163052.00,4118.964217,N,07036.966471,W,4,10,00.9,00005.332,M,-030.544,M,01,*57 UTC Time = 163052 Latitude = 4118.964217 N Longitude = 7036.966471 W Fix Quality = 4 Number of satellites = 10 HDOP = 00.9 relative accuracy of horizontal position Altitude = 5.332 meters above mean sea level Height of geoid above WGS84 ellipsoid = -30.554 meters Time since last update = 01 Checksum = *57.
$GPVTG is track made good and ground speed in the format "$GPCTG, true, T, mag, M, grsp, N, grdp, K, mode", where t=true course made good over ground in degrees, T= True, m=magnetic course made good over ground in degrees, M=magnetic, gdsp=ground speed, N=Knots, grsp=ground speed, K=Kilometers per hour, mode=Mode indicator (A=Autonomous, D=Differential, E=Estimated, N=Data not valid).
Example: $GPVTG,089.23,T,104.82,M,004.86,N,009.02,K,D*28 True course made good: 089.23 Magnetic course made good: 104.82 Ground speed (knots) = 4.86 Ground speed (kilometers) = 9.02 Mode=Differential
$GPZDA is UTC Date/Time and Local Time Zone Offset in the format "$GPZDA,hhmmss.ss,xx,xx,xxxx,xx,xx" where hhmmss.ss=UTC, xx=Day, 01 to 31, xx=month, 01 to 12, xxx=Year, xx=Local zone description, 00 to +/- 13 hours, xx=Local zone minutes description (same sign as hours), checksum.
Example: $GPZDA,163053.00,09,08,2007,,*60 UTC= 163053.00 UTC day = 09 UTC month = 08 UTM year = 2007 Local zone hours = null Local zone minutes = null Checksum = *60
(508) 548-8700x2311 (voice)
5084572310 (FAX)
jdenny@usgs.gov
These data are supplied to provide the raw navigation collected by an Ashtech Z-Extreme receiver and logged using HYPACK, Inc. navigation software (www.hypack.com). RTK navigation was not incorporated to any of the geophysical systems during data acquisition. These data were stored in order to post-process the RTK navigation to provide improved vertical and horizontal accuracies for the swath bathymetric data. RTK provides accuracies on the order of 10s of centimeters (<http://www.navcen.uscg.gov/>).
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Raw navigation data were saved in HYPACK format (<http://www.hypack.com>). File name convention is LLL_TTTT.DDD, where LLL is the HYPACK line number, TTTT is the 24 hour time (UTC) for the beginning of the file, and DDD is the Julian day. Times in the file were recorded in UTC (Coordinate Universal Time).
Person who carried out this activity:
(508) 548-8700 x2311 (voice)
(508) 457-2310 (FAX)
jdenny@usgs.gov
HYPACK, Inc, 2009, HYPACK Hydrographic Survey Software User Manual.Online Links:
Real-Time Kinematic (RTK) data were collected using an Ashtech Z-Extreme receiver and were processed and recorded using navigation software from HYPACK, Inc (<http://www.hypack.com/>). These data were not incorporated into the geophysical data during acquisition. These data were stored in order to post-process the RTK navigation to provide improved vertical and horizontal accuracies for the swath bathymetric data during post-cruise processing. RTK provides accuracies on the order of 10s of centimeters (<http://www.navcen.uscg.gov/>).
Data from the Z-Extreme were also logged to Ashtech's Geodetic Base Station Software (GBSS), and recorded locally to hard disk. GPS signal correction data from a Z-Extreme base station located at the USGS warehouse facility were transmitted via radio modem out to the ship. These data were used by the HYPACK software to provide height offsets from the WGS 84 ellipsoid. These offsets were then translated to water level heights based on the 2003 geoid model (see: <http://www.ngs.noaa.gov/GEOID/GEOID03/> for more information), which approximates mean seal level (MSL).
These files represent all the real-time kinematic (RTK) navigation recorded by the HYPACK software during USGS cruise 07011 off the southern shore of Martha's Vineyard, 2007.
These are the original raw data files recorded by the HYPACK navigation software. No additional checks or corrections have been made to these files.
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) 548-8700 x2311 (voice)
(508) 457-2310 (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: | This WinZip file contains the ANSI text HYPACK navigation files as well as the associated metadata files. in format WinZip (version 9.0) Size: 27 MB |
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Network links: |
<https://pubs.usgs.gov/of/2008/1288/GIS_catalog/Nav/hypack.zip> |
The user must have software capable of uncompressing the WinZip file, such as WinZip or pkUnzip.
(508) 548-8700 x2311 (voice)
(508) 457-2310 (FAX)
jdenny@usgs.gov