volcanic ass eruption 

An explosion of the rectum after eating too much food the night before.

Or

After a holiday dinner at a relatives house and you eat something that doesn't agree with your system causing irritable bowel syndrome resulting in burning or the rectum and violent ass eruptions associated with bubbling gas in the stomach nicked named "bubblin' brown sugar".

Man dem greens, macaroni and cheese hit the spot...boy! Rumble, rumble...poot, poot, fissssst. Ooooh!....Oooooooh!....Somebody help me please!...Where da bathroom at...pooot, pooot, fisssst. blurrrrrrt.....fisssst.

Ooooohwheee! got dem bad guts...what yo mamma put in dem greens man?! I gotta doodoo bad baby got a volcanic ass eruption comin' thru!

volcanic ass eruption by lil dookie November 5, 2013