Berf' Quake 

When thicc girl such as a PAWG shakes her large glutius maximus aka Berfday cakes (Birthday cakes) during a twerk or similar dance move and the shock and ripple effect that takes place is known as a berf quake.

2 guys at a generic party....
Guy1: Oh shit do you feel that?!
Guy2: Brace yourselves!!! BERF' QUAKE!!!!

Berf' Quake by Lil pimpchop May 6, 2019

Beefquake 

It is exactly what it sounds like it is.

Mike, you stinky bitch. Don't make me fuckin' beefquake upon you.

Beefquake by Thickle June 19, 2018