OCC coding question- MH and WH

I've been monitoring a few counties in Oklahoma and have ran across well names coded with MH often. Today I see one coded with WH. I've unconfidently understood MH to mean horizontally producing multiple depths in the same hole - and would like very much to be corrected with a better understanding if needed. Even if that's what it means I still have questions too. I haven't got a clue what WH would mean. Anybody care to teach a novice a little more about this coding on OCC?

Here are today's examples. Looking like they're on the same section to me.

MH - http://imaging.occeweb.com/OG/Well%20Records/1DD0988F.pdf

WH - http://imaging.occeweb.com/OG/Well%20Records/1DD09890.pdf



Maybe it's a Devon code, don't recall anyone else using those.