The Shock Barrier is a minor object found in the Fault Line on the planet Arcterra. Its purpose is to guard valuable cargo from intruders. Samus can turn the Shock Barrier off by scanning the Gun Turret CPU nearby.
"Controlled by a nearby console. This portable security system is placed in close proximity to valuable cargo. The beam emitted by the shock barrier can neutralize all but the most heavily armored intruder."