What is the name of this bass line pattern?

For the 40 pieces a year challenge, I started with something simple (Oh! Susanna):

Actually too simple! Especially the bass line is very boring. I want to beef the bass up with this line instead:

I am quite sure, this one is used a lot in folk music, but does anybody know it's name?

Until now, I would call it Oompah-Oompah pattern. I am quite sure, this is wrong, what is the real name of that?

According to Lucinda Mackworth-Young (Piano by ear) it's called pub (or knees-up) style accompaniment.

I think Oompah is fine: