SRTM (Shuttle Radar Topography Mission) are the most popular datasets on the Geosoft DAP Server. These grids make a great base group on a regional scale map or a relief surface to drape other data on in 3D. The entire dataset – 90m World or 30m US – is very large (originally, it was delivered on a stack of DVDs). Using DAP, any chunk can be downloaded in a few easy steps. Here’s how:
1. Using Seeker through Oasis montaj, Target, ArcGIS (with Target for ArcGIS or the Plugin for ArcGIS), or MapInfo (with the Geosoft Plugin for MapInfo), open Seeker.
2. Define the Area of Interest, by repositioning the red Area of Interest outline, double clicking on the longitude or latitude values to edit them, selecting a region from the list, loading an area of interest from a file (there are a number of supported formats), or refreshing from your open map (if applicable).
3. Optionally, narrow the results by adding text search criteria such as a keyword like “SRTM”.
4. In the Results for the Geosoft DAP Server, the SRTM World Elevation 90m and SRTM US Elevation 30m will appear (as long as they intersect with your area of interest).
Note that these data do not extend past 60N or 60S. If you are looking for topography data in these regions, GLOBE DEM and SRTM30 Plus are also available on the Geosoft DAP Server.
5. Select the topography dataset. Move to the Cart tab and adjust the download options to your preferences. This may include changing the format or reducing the resolution (often, the original resolution is desired so select the Do Not Resample option if you have selected several datasets).
6. Click Retrieve, and the topography for your area of interest will be downloaded to your Destination Folder.
If you are not using a Geosoft application or plugin, then the same datasets are also available from the Geosoft DAP Server web interfaces. Visit http://dap.geosoft.com/geodap or http://dap.geosoft.com/flamingo.