This submodel contains the classes and associations that describe a perforation activity. Perforation is the act by which communication tunnels are created from the casing or liner of the wellbore into the reservoir formation, through which oil or gas can be produced. The most common method uses jet-perforating guns equipped with shaped explosive charges. Detonating a shaped charge creates a jet of hot gas, which in turn creates an opening in the casing and travels into the reservoir.