Do you mean more like this?

In this example there are two circles. Both are affected by the Edge Fade, Inner, which is as wide as the radius of the outer circle minus the radius of the inner circle. The inner circle is the knockout colour of the Color Key, which subtracts the inner circle, leaving a ring. Then the Blur fades the inner extent. The blend mode is just to further reduce the transparency and make it more part of the background than something hovering in front of it. In this example I used Screen and left transparency at 100%

I'm not sure how smooth the result will be when rendered out. This is my image at 3000 px square, but if you export too large you may end up with rendering issues.

Even with screen shots it's pretty difficult to work out what is happening here.

Maybe this tutorial by Dogtag will help?

https://forum.profantasy.com/discussion/6723

Here's another try :)

Click the image to see it larger.

I think shovelled pathways may be more in the realm of dungeon scale, but I do have a sheet and tool for drawing hills that could be duplicated (both the sheet and the tool) and adjusted to draw smaller drifts.

Thank you, AleD :)