To be honest it looks a bit like a stylized map of Blackwater Bay (rotated), with Dragonstone and Driftmark being the main islands in the bay.
Some of the details are definitely off, but that could be consistent with imperfect maps and perhaps some distortion in the making of the seal and then some more in the way the seal came out this time, the angle we're looking at it being shot from, and so on.
It might well be a wolf as the first answer indicated (I finally figured out the intent would be a wolf facing left in the picture), but the first impression I had was of islands in a bay.
Edit: after playing about with the images for a bit, I've come to the conclusion that it is just as Rowan Freeman suggested:
So while I now think Rowan's answer is likely correct and my suggestion here is likely wrong, I'll leave this here, at least for now.