What's the buzz? A powerful tremor shook large parts of Gauteng during the early hours of Sunday morning.

The national Council for Geoscience said Sunday morning's tremor in Gauteng measured a magnitude of 4.4. The council's website earlier stated the magnitude at 4.7.
The earthquake's epicentre “was located in the Boksburg area a few kilometres outside East Rand Proprietary Mine, in the East Rand of Johannesburg”.

Guest: Prof Ray Durrheim, School of Geoscience at Wits