mud cake (oil and gas)

Mud cake (also mudcake) is the layer of particulates from drill mud coating (caking) the inside of a borehole after the suspension medium has seeped through a porous geological formation.{{Cite web |title=mudcake |url=https://glossary.slb.com/Terms/m/mudcake.aspx |access-date=2025-06-27 |website=glossary.slb.com |language=en}} Similar to filter cake.

Mud cake provides a physical barrier to prevent further penetration and loss of drilling fluid, as well a later loss of produced fluids, into a permeable formation.{{Cite web |title=formation_damage |url=https://glossary.slb.com/en/Terms/f/formation_damage.aspx |access-date=2025-06-27 |website=glossary.slb.com |language=en}}