If you blow it up on the surface or in the atmosphere, sure. Blow up a 10 gigaton device, which we absolutely can make and have the materials to do so, buried as deep as you can possibly get it, so about 1.5-1.6 miles in the crust, and you're gonna wreck a significant portion of a hemisphere.

Especially since U-238 is one of the most abundant elements in the crust. Literally every single shovel full of dirt that you pick up has several hundred to several million atoms of U-238