 The five provinces bordering the Gulf of Saint Lawrence also have several provincial parks apiece, some of which preserve coastal features.The Laurentian Channel is a feature of the floor of the Gulf that was formed during previous ice ages, when the Continental Shelf was eroded by the Saint Lawrence River during the periods when the sea level plunged.The Laurentian Channel is about deep and about long from the Continental Shelf to the mouth of the Saint Lawrence River.