Roof pendant

Mass of rock that projects downward into and is entirely surrounded by an igneous intrusion

In structural geology, a roof pendant, also known as a pendant, is a mass of country rock that projects downward into and is entirely surrounded by an igneous intrusion such as a batholith or other pluton. In lay terminology sometimes "rock hat" is used. A roof pendant is an erosional remnant that was created by the removal of the overlying country rock that formed the roof of the igneous intrusion that encloses it. If this downward protruding mass of roof rock still has a connection to the main, surrounding mass of country rock, they are known by structural geologists as either septa or screens. Roof pendants typically have been strongly metamorphosed through the processes of contact metamorphism.

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