Lynette Louw (Barberton Times)

It is by now common knowledge that Barberton’s rocks are of the oldest in the world. With the town being included in the proposed World Heritage Site (WHS), Barberton will be put on the map in a big way. Scientist from all over the world, including some of Nasa have visited Barberton in the past to study the formations.

The Geological Society recently took a group of interested people on a geological trail up the Bulembu road. Dion Brandt, consulting geologist of the WHS project with Chris Rippon, a geologist at Barberton Mines, gave interesting facts at various stops on the trail.

The society plans to mark certain areas on the road with plaques explaining the significance of the rock formations.

According to Dion, Prof Christoph Heubeck of the Free University of Berlin did a thesis on the rocks of this area. He said the site included the best examples of the most important geological exposures. Some of them was shown on the route, one being formations containing the first microfossil evidence of life on earth, such as stromatolites and biomats, which can actually be seen with the naked eye.

He showed pillow lava balloons indicating widespread underwater volcanic eruptions and spherule beds, remnant of the earliest recorded and probably the largest asteroid impacts on earth.

At the Sheba fault a thick band of dark coloured iron-rich chert is seen. Dion said it was formed by the chemical precipitation of silica in a quiet see floor environment. Bacterial microfossils have been discovered in the chert, evidence that there was life even in the early stages of formation of the planet.

At this spot the open stopes of the May Mine could also be seen which produced 188 kilograms of gold from 1932 to 1933.

At the Moodies group sedimentary rocks, Dion explained that this was evidence of the oldest tidal environments on earth, suggesting that the moon was in orbit at this early stage of the earth’s history.

Other interesting rocks bearing signs of herringbone cross-bedding, pillow lavas, baryte mineralisation, conglomerates and ripple marks produced by water flow over sediment, were shown and explained.

Some of these formations were exposed due to the excavations and rebuild of the Bulembu road and would otherwise not have be known. It is our duty to preserve this for future generations.

Dion Brandt shows some iron rich chert indicating the there was life in the early stages of formation of the planet.

Chris Rippon at the conglomerate quarry.

Dion Brandt explaining pillow lavas.