A Gravimetric pulse is a manifestation of gravimetric energy which can have a number of effects.
The Gravimatrix, an energy production facility on the planet Tigan accidentally generated a gravimetric pulse when it was being tested. The pulse wiped the Tigan central computer. After that first accident pulses were purposefully generated to wipe parts of the core so that Tigan conspirators could selectively rewrite Tigan history.
The Tigans also used gravimetric pulses as weapons. They fired a gravimetric pulse at the USS Enterprise-D which pushed the Enterprise in a gravimetric wave at high velocities across the galaxy. The Enterprise was only able to break free by using the slingshot effect. On a smaller scale the Tigans also used a weapon called a graviton gun, which had a similar repulsive effect. (TNG comic: History Lesson)