A geological pothole is a natural depression in the rock filled with cooled magma, creating a fault.
In horizontal section, potholes are roughly circular to elliptical and vary in diameter from 20 m to more than 1 km.
[1] Potholes are frequently encountered during mining operations in the Bushveld Igneous Complex in South Africa.
The massive intrusion of molten magma, predating the nearby Vredefort impact by at least 30 million years,[2] led to partial to complete melting of the cumulus floor already in place.
In the Bushveld Igneous Complex, two orebodies, the Upper Group 2 (UG2) and the Merensky Reef, host about 70% of the world's platinum group metals (PGM), and pose major extraction problems for the mining industry in their faults, dykes, joints, domes, iron-rich ultramafic pegmatoids, rolls and dunite pipes.