Section 1: Past
THE TEXT-BOOK VERSION:
Earth is an amalgam
of hatreds stone and love,
of clay and iron hopes.
~ Rui de Matos, `Geology Lesson'.
A sinkhole is a subsidence which appears suddenly, and sometimes with catastrophic consequences, as a cylindrical and steep-sided hole in the ground. It is usually, but not always, circular in plan, and may be up to 125 metres wide and 50 metres deep. If the dimensions exceed 45 metres in diameter and 30 metres in depth, it is regarded as a large sinkhole.
3 August 1964
A sinkhole ... appeared in a mining village at Blyvooruitzig Mine (Oberholzer Compartment) in the middle of the night and claimed the lives of the Oosthuizen family of five as their house suddenly dropped more than 30 m. Three other houses which were situated on the edge of the initial collapse also fell in within a short period of time as the sides of the sinkhole caved in, their occupants making dramatic escapes. Subsequent enquiry revealed that there had been leakage from water pipes in the area where the sinkhole appeared.
A.B.A. Brink, Engineering Geology of Southern Africa: The First 2 000 Million Years of Geological Time (Pretoria: Building Publications, 1979).