Keep blowing 30 amp fuse off of battery

I got stuck in some muskeg got towed out started back down the trail hit a bump lost power,checked and the 30 amp fuse right off of the positive battery connection was blown replaced fuse turned the key and it blew again.Towed it home clean all the mud from everywhere,cleaned terminals checked wiring replaced fuse turn ignition on and fuse blows again,replaced again just touch key didn't even turn the key and it blew again just wondering if my problem may be in the ignition switch anyone else have this problem.

Thanks