GeoIS-EM Home         Coastal topobathy data processing

Helena Mitasova, NCSU

Gridding single beam profile data for Mason Inlet using standard IDW method (oversampling along profiles that are far appart, the result has many artifacts and cannot be used to generate a mask):

IDW DEM and point data IDW DEM only

Gridding using spline with default parameters allows us to derive a mask using contours (0.2 and -29.0) without hand digitizing (few points were added to make it easier) and the result can then be masked only to areas where we have points. The interpolation parameters are then tuned to minimze the waves along profiles and the result is masked to areas where we have point coverage. For areas where the profiles are particularly far appart - we ware working on methods to optimize selection of points to further minimize the effect.

Initial DEM, contours Tuned and masked Gridded bathy

CRM problem Oregon Inlet New River Inlet

Topsail Inlet

Channels: data detail and patched with CRM

a b c d

Processed and visualized
by GRASS6