Resolved How to do a blast against the ground, sending a character flying

Of course it's possible because you're just asking, "can you perform a query to detect something" and "can you apply a force to move in a specific direction". I get a sense that you're instead asking if someone could write some code for you instead.

I would suggest if you don't know how to perform queries then go search for one of the many tutorials on the subject. Applying a force to a Rigidbody is a super basic thing too so if you feel you need it, go look-up a tutorial on that too. Combining the two things is then simple.