DELILAH Bathymetric Surveys

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The DELILAH survey data were collected using the Coastal Research Amphibious Buggy or CRAB, a 10-m tall self-propelled tripod. Position of the CRAB was determined using a Geotronics 140T auto-tracking total station. This system aims an infrared beam at a reflecting prism mounted on the CRAB and measures the spherical coordinates associated with each position. The Geodimeter 140T tracks the CRAB and samples at 1Hz. There were errors associated with the Geodimeter (vertical noise and drifting) which are described in the Survey Section.

The data files are all in ASCII format. The plot files are available in two different file types, Graphics Interchange Format (GIF files) and Computer Graphics Metafiles (CGM files). The gif files can be viewed by clicking them. The cgm files are vector based and supported by most CAD, word processing, and drawingprograms.

DELILAH MiniGrid Surveys

2D MiniGrid Survey Data
The cross-section data are displayed as comparison plots between successive surveys of all lines surveyed. The files are named by date (YYMMDD) according to the second day of the comparison. For example, the file containing the comparison plot between surveys on October 10 and October 11, 1990 is labeled DE901011.GIF (.CGM). The data file used for these plots is DELILAH.2d and described under DELILAH Survey Data: 2d Format.

CGM Files
DE901002 DE901003 DE901004 DE901005 DE901006 DE901007 DE901008 DE901009 DE901010 DE901011 DE901012 DE901013 DE901014 DE901015 DE901016 DE901017 DE901018 DE901019
GIF Files (viewable)
DE901002 DE901003 DE901004 DE901005 DE901006 DE901007 DE901008 DE901009 DE901010 DE901011 DE901012 DE901013 DE901014 DE901015 DE901016 DE901017 DE901018 DE901019

3D MiniGrid Survey Data
The filenames are labeled by date from October 1 through October 19, 1990. The date in the filename is preceded by the letters "MG"(for minigrid). For example, the file for October 3, 1990 is labeled MG901003.GIF. An example plot is shown below. The DELILAH minigrid survey data presented in the 3D-format data files contains the survey line number, x (cross-shore) , y (longshore) and z (depth relative to NGVD) coordinates in meters. Coordinates are relative to a pier-orthogonal system whose origin is located behind the dunes and along the FRF's south property boundary.

Sample: 3D Minigrid Format line:

DE170   2901001  907        89.682   1282.351      2.837 

Each data line uses the following FORTAN format:

Locality Code (DE for DELILAH)           A2
Profile Line number                      A3
Survey number                            I4
Date (YYMMDD)                            I6
Computer Clock Time (EST in HHMM)        I5
X coordinate (cross-shore in m)          F11.3
Y coordinate (longshore in m)            F11.3
Z coordinate (elevation, m NGVD)         F11.3

3D survey data files are ASCII files containing all profile lines surveyed during a single survey. The filenames include the survey date. For example, the file containing survey data collected on October 12, 1990 is labeled DE901012.3d.
3d Contour Plots & Data
DE901001.3d   MG901001.gif   MG901001.cgm
DE901002.3d   MG901002.gif   MG901002.cgm
DE901003.3d   MG901003.gif   MG901003.cgm
DE901004.3d   MG901004.gif   MG901004.cgm
DE901005.3d   MG901005.gif   MG901005.cgm
DE901006.3d   MG901006.gif   MG901006.cgm
DE901007.3d   MG901007.gif   MG901007.cgm
DE901008.3d   MG901008.gif   MG901008.cgm
DE901009.3d   MG901009.gif   MG901009.cgm
DE901010.3d   MG901010.gif   MG901010.cgm
DE901011.3d   MG901011.gif   MG901011.cgm
DE901012.3d   MG901012.gif   MG901012.cgm
DE901013.3d   MG901013.gif   MG901013.cgm
DE901014.3d   MG901014.gif   MG901014.cgm
DE901015.3d   MG901015.gif   MG901015.cgm
DE901016.3d   MG901016.gif   MG901016.cgm
DE901017.3d   MG901017.gif   MG901017.cgm
DE901018.3d   MG901018.gif   MG901018.cgm
DE901019.3d   MG901019.gif   MG901019.cgm

Grid Survey Data
The grid format of the minigrid survey data consists of longshore distance (in meters) in the first row of data, and cross-shore distance (in meters) in the first column. The remaining 25 columns of data are the depths at the corresponding longshore and cross-shore position (in centimeters) relative to NGVD. Each grid cell comprises a distance of 24 m in the longshore and 8.75 m in the cross-shore.

A sample section of the file is shown below. The first line includes a project descriptor (33 characters), date (11 characters), number of profile lines surveyed (5 characters), description of depth units and datum (30 characters). This is followed by a blank line, then a row defining the longshore distance for each column and another blank line. The remaining lines include the cross-shore distance and depth data.

  DELILAH Minigrid, Duck NC      1990 OCT  7   19   Depths in centimeters, NGVD 

 DIST,m  725  748  772  796  820  844  868  892  916  940  964  988 1012 1036 ....

   50.0  748  809  703  677  721  744  722  699  701  704  698  684  678  670  662
   58.8  627  620  609  573  635  620  682  682  662  693  683  646  642  642  643
   67.5  403  402  381  408  404  415  419  492  444  517  522  511  503  526  537
   76.3  203  209  214  223  234  266  297  304  329  333  339  354  377  363  362
   85.0  156  165  171  182  186  213  243  251  284  284  292  301  315  307  308
   93.8   85  108  117  122  111  116  112  149  155  210  230  246  257  270  283
  102.5    5   27   40   50   35   23   16   54   78  134  153  159  166  174  184
  111.3  -52  -30  -14   -5  -19  -29  -39  -22    0   52   81   89   88   79   75

Grid format data files include a single minigrid survey and are labeled by date with the first two characters of each filename being DE (for DELILAH). For example, the data file from October 1, 1990 is labeled DE901001.GR

Grid Data Files
DE900919.GR   DE901001.GR   DE901002.GR   DE901003.GR   DE901004.GR

DE901005.GR   DE901006.GR   DE901007.GR   DE901008.GR   DE901009.GR

DE901010.GR   DE901011.GR   DE901012.GR   DE901013.GR   DE901014.GR

DE901015.GR   DE901016.GR   DE901017.GR   DE901018.GR   DE901019.GR  

13m-Deep Surveys

The DELILAH 13-m deep survey data in the 3D-format data file contains the survey line number, x (cross-shore) , y (longshore) and z (depth relative to NGVD) coordinates in meters. Coordinates are relative to a pier-orthogonal system whose origin is located behind the dunes and along the FRF's south property boundary.
Sample: 13m-Deep 3d Survey Format
39183   1900627 1012       476.982    182.880     -4.511
SL 33   1901115 1200       802.886   1098.228     -7.120
39 73   1121212    0       800.000    800.000     -7.160
Each data line uses the following format:
Parameter and FORTRAN Format specification

Locality Code (see explanation below)  A2
Profile Line number                    A3
Survey number                          I4
Date (YYMMDD)                          I6
Computer Clock Time (EST in HHMM)      I5
X coordinate (cross-shore in m)        F11.3
Y coordinate (longshore in m)          F11.3
Z coordinate (elevation, m NGVD)       F11.3

The 13m-Deep survey data includes profile lines surveyed by both the CRAB and Sled. CRAB survey lines are indicated by a Locality code of "39", Sled survey lines are indicated by an "SL." A portion of the data in the north-eastern corner of the contour plot was extrapoloated from adjacent points. These data are indicated by a locality code of "99."

13-m Rectangular Grid Format Data

The rectangular grid format file consists of longshore distance (in meters) in the first row of data, and cross-shore distance (in meters) in the first column. The remaining 55 columns of data are the depths at the corresponding longshore and cross-shore position (in centimeters) relative to NGVD.

Each grid cell comprises a distance of ~30 m in the longshore and 13.5 m in the cross-shore. The depths are in centimeters relative to NGVD. A sample section of the file is shown below. The first line includes a project descriptor (33 characters), date (11 characters), number of profile lines surveyed (5 characters), Description of depth units and datum (30 characters). This is followed by a blank line, then a row defining the longshore distance for each column and another blank line. The remaining lines include the cross-shore distance and depth data.

Sample section from 13m_deep.gr rectangular grid data file

 DELILAH 13-m Deep Survey, Duck NC      1991 JAN 18   Depths in centimeters, NGVD

 DIST,m  -100   -70   -41   -11    19    48    78   107   137   167   196   226   256

   50.0   678   540   501   625   588   680   671   659   721   634   650   721   621
   63.5   534   453   492   526   494   580   555   546   542   526   532   526   496
   76.9   296   306   325   303   313   289   315   323   333   360   359   352   340
   90.4   236   236   288   264   244   289   260   260   280   271   273   282   255
  103.8    95   107   148   144   135   147   158   160   187   175   180   175   161
  117.3   -67   -43   -23   -17    -7   -31    12    10     0     9    21    37    33
  130.7  -119   -93  -107  -114   -89  -108   -93   -87   -99   -76   -75   -94   -58
  144.2  -112  -107  -117  -121  -109  -122  -100   -93   -67   -81   -79   -50   -60
  157.6  -103  -107  -113   -87   -98  -119   -82   -75   -55   -95   -95   -63   -75

Gridded data files are labeled by date with the first two characters of each file name being DE (for DELILAH). For example, the data from October 1, 1990 is labeled DE901001.GR.

13-m Deep Survey Plots

Contour and perspective plots of 13-m deep survey data are provided in three formats gif, cgm and eps. The latter provide high quality images that can easily be manipulated and scaled. The two plots are shown below.


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