How do clams burrow themselves in the sand?

It is commonly thought that clams have a muscular foot that they use to help them dig into the sand. The foot grasps deeper and deeper making its shell body move with it, and with this foot, they can almost completely bury themselves. However, this is not the case with all clams, especially since the foot, although muscular, does not have that much strength, judging by scientific measurements done on the strength of this muscle.

The razor clam, for example, actually creates quicksand around itself which helps it to burrow and sink down into the sand. It first creates an empty space in the sand below its foot, which it does by constricting valves within its shell. The water rushes into the empty space to fill it, making the sand softer. As the clam's muscular foot continues to churn the sand to dig down, it essentially creates a soft and slushy quicksand which is even easier for the clam to penetrate.