I'm trying to create an outline of a complex polygon. The polygon in question can be seen here (edit: I've attached the images below). This is an elevation model of an alluvial flow. As you can see, there are many little "islands" in the middle of the flow. I just want the greater outline of the flow, as demonstrated here (a poor hand-made outline in MS Paint...). For a sense of scale, this is about 10 km wide.
The attribute table for the polygon only has a single row, so I can't just edit out the islands. I've tried Buffer, Dissolve, and Union, all basically end up looking about the same.
Any advice on how to proceed would be appreciated.
Solved! Go to Solution.