| Surv Id | Format | Ngdc Id | Params | Create Date | Source Institution | Seq | ||
| 4 | L01968 | HYD93 | 03L11106 | SF | 19791231 | National Ocean Survey, N.O.A.A. | 01 |
| Country | Platform Name | Plat Type | Chief Hydrographer(s) | Seq |
| U.S.A. | Unknown Ship | 1SHIP | 02 |
| Project | Type of Survey | Strt Yr | End Yr | Scale of Survey | Seq |
| 1956 | 1956 | 03 |
| Area (General) of Survey | Area (Specific) of Survey | Seq |
| LAKE HURON | 04 |
| Quality of Survey Description | Processing Status Description | Seq |
| 05 |
| Position Determination | Seq |
| 06 |
| Code | Horizontal Datum of Records | Code | Original Horizontal Datum | Seq |
| NOS31 | North American Datum 1983 | NOS06 | North American Datum 1927 | 07 |
| code | Vertical Datum | tide | Original Sounding Units | Seq |
| see comments | feet | 08 |
| Sounding Method | Seq |
| Digital Echo Sounder w/ Graphical Record assumed | 09 |
| c | Sound Velocity Correction | Seq |
| 1 | Corrected for actual sound velocity | 10 |
| Data Processing Methodology | Seq |
| Smooth sheets digitized for N.O.S. under Ashville Contract | 11 |
| Format of Data Records | Top Lat | Bottom Lat | Left Lon | Right Lon | Seq |
| SURV,LAT,LON,VAL,TYP,CCODE(A8,F9.6,F10.6,F6.1,I1,I3) | +43.13 | +43.06 | -82.50 | -82.37 | 12 |
Additional Documentation |
Seq |
| VERTICAL DATUM - SOUNDINGS ARE REDUCED TO LOW WATER DATUM WHICH FOR LAKE HURON | 13 |
| IS 578.5 FEET ABOVE MEAN TIDE AT NEW YORK, 1935 DATUM. | 14 |
| 15 | |
| 16 | |
| 17 | |
| 18 | |
| 19 | |
| 20 | |
| 21 | |
| 22 | |
| 23 | |
| 24 |
Note: You can find the comnplete HYD93 Format Specification, including all code descriptions, at www.ngdc.noaa.gov/mgg/dat/geodas/docs/hyd93.htm