SOURCE MATERIAL 



Bathymetric contour charts instead of recorded water depths, 

 are the source for the SYNBAPS data base. No computer algorithm 

 (glossary) that can successfully handle all qualities of bathy- 

 metric-track-line data, resolve all navigational errors, and can 

 apply a contouring philosophy to such data has been developed. 

 These functions require the subjective judgement, based on 

 knowledge of geologic processes, of the bathymetrist whose final 

 product is the bathymetric contour chart. The bathymetrist ' s 

 very subjectivity creates the data continuity which is a requisite 

 element of SYNBAPS. A long profile requires on omnidirectional, 

 continuous data base, something that is seldom achieved with 

 either survey or random ship track line data alone. Using areas 

 having high quality and dense data coverage as a framework, the 

 bathymetrist extends, interpolates, and extrapolates regional 

 trends into areas of lesser data to build a continuous picture 

 of the submarine topography. 



Although SYNBAPS is designed for worldwide application, 

 initially a data base will be created only for the Northern 

 Hemisphere, and possibly the Indian Ocean. Other regions will 

 be added to the data base when sufficient continuous data become 

 available. The charts used for the North Pacific Ocean will be 

 large to medium scale (1:1,000,000 or larger) versions of the 

 U.S. Naval Oceanographic Office H.O. Pubs. 1301, 1302, and 1303 

 (U.S. Naval Oceanographic Office 1969, 1971A and B) . Recent 

 unpublished large-to-medium scale charts compiled by the U.S. 

 Naval Oceanographic Office will be utilized for the North Atlantic 

 and Mediterranean Sea. Where applicable, classified data can be 

 incorporated in the data base without compromising security. The 

 gridded data point from a classified chart, which was contoured 

 from classified data or from a mixture of classified and unclassi- 

 fied data, will be indistinguishable from a data point from an 

 unclassified chart. Only the originator will know which depth 

 values were created from classified data and that they may be 

 more accurate than other points. The originator will keep a 

 separate noncomputerized file, indexed by MSQLOC areas, showing 

 the source of the contours, their evaluation, classification, 

 and other pertinent information. There will be no reference to 

 original track spacing, area limits, navigation, sounding device, 

 or platform within the data base. Preparation of the charts for 

 digitization is discussed in more detail in appendix A. 



SYSTEM DESCRIPTION 



A. Structuring Programs 



11 



