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.
Sample: 3D Minigrid Format line:
Each data line uses the following FORTAN format:
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.
Grid Survey Data 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. 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
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."
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
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.
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. DELILAH Home | Overview | Surveys | Video | Sediment | Calibrations | Instruments | Sled | People & Reports | Data | Report
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.
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.
DE170 2901001 907 89.682 1282.351 2.837
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
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.
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
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
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.
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
13-m Deep Survey Plots