Smoke and lava generally escapes from a shield volcano through the but they can also escape through a flanking vent

Smoke and lava generally escape from a shield volcano through the caldera. A caldera is a large, special form of volcanic crater formed by the collapse of a volcano into itself. The emptying of the magma chamber beneath the volcano triggers the caldera to collapse, resulting from a large volcanic eruption.

Ascenario that doesnt  include any modern objects like electricity