The format used for reporting the results cf bathymetric surveys is usually a map. The most effective map is one that is clearly drawn and annotated. The drafter of the map should keep in mind that others will be needing the map for various purposes. The map should be large enough to include all pertinent information but not so large as to become difficult to handle in the field. Figure 4-19 is a typical map made from a UCT bathymetric survey. The datums used for the survey and the location and elevation of all benchmarks used should be clearly indicated. The relationship of the datum used to any other datums in the area, if known (e.g., MSL, MHW, MLW), should also be indicated. It is sometimes advantageous to plot findings as overlays to maps made by the National Ocean Survey or similar agencies; this will eliminate the expense of making an entire map and will also make the information transferable to any standard map.
The raw data should be reduced and processed to create field working plots so that any missing information can be obtained, and conflicting or erroneous data corrected before leaving the site. The raw data should be included in the final report along with reduced data and maps.
The bathymetric information along a proposed cable or pipeline route is often presented as a profile showing depth as a function of distance. The vertical scale should be about 10 or 20 times the horizontal scale, as shown on Figure 4-20. When slopes are critical, it is advisable to show the critical slope at the plot scale as part of the legend.
The results of visual surveys are usually presented in the form of a brief report describing the findings with relevant photographs attached (NFESC has a procedure to embed digital photos into AUTOCAD drawings, this is a good way to file the photos). The report is usually issued as an attachment to the bathymetric survey results.
The results of geophysical surveys along a cable or pipeline route are generally presented as a projected profile of seafloor soil material classification and pertinent properties versus elevation along the route. The vertical scale is usually 10 or 20 times the horizontal scale, as shown in Figure 4-21.
The results of location surveys and quality control surveys, as well as the other surveys described above, should be presented in a project completion report. A sample outline for a typical project completion report is given in Section 1.7.
Was this article helpful?
Although we usually tend to think of the digital camera as the best thing since sliced bread, there are both pros and cons with its use. Nothing is available on the market that does not have both a good and a bad side, but the key is to weigh the good against the bad in order to come up with the best of both worlds.