Description of Field Research Facilty's SandyDuck Survey Files

During the SandyDuck experiment, a region referred to as the SandyDuck Minigrid was surveyed 
repeatedly. The minigrid was located north of the FRF research pier and extended longshore 
from FRF coordinate of 550 m to 1300 m north.  The data  were collected using a 
Trimble 4000 SSE differential GPS survey system, Coastal Oceanographic's HYPACK hydrographic 
survey software, and the Coastal Research Amphibious Buggy or CRAB.
 
The data were collected relative to the FRF's local coordinate system.  Units are m and depths 
are relative to the National Geodetic Vertical Datum (NGVD) of 1929. 

The minigrid data are provided in 5 file types - all files are coded by date and extension.

1) 3d files (*.3d) - referred to locally as "ISRP 3D" format files, these store the original data
from each minigrid in an ASCII format of one survey point per line. (See Readme_3d.txt for explanation)
2) Matrix files (*.mat) - these are rectangular depth matrices computed for each survey from the 
*.3d files (See Readme_Mat.txt for explanation)
3) Graphs - There are two different plot types and two formats (gif, and postscript).  Contour plots
in either format are labeled as type "a" (ie. SD971008a.gif or SD971008a.ps) while perspective plots
are type "b" (ie. SD971008b.gif or SD971008b.ps).  Both plot types include locations of installed 
SandyDuck instruments.

For more information about these data and the FRF visit the web site at http://frf.usace.army.mil/ 
or contact either Mike Leffler or Bill Birkemeier at 919-261-3511.  Any use of these data should 
credit the US Army Corps of Engineers and the Field Research Facility. 

Readme file updated 17Apr2002, wab

US Army Corps of Engineers, Engineer Research and Development Center
Coastal and Hydraulic Laboratory
Field Research Facility, 1261 Duck Rd, Duck, NC 27949
252-261-3511x229, 252-261-4432(fax)
http://frf.usace.army.mil