Oldest part of the Netherlands is 420 million years old and found in Zeeland

For a long time it was thought that the 330 million year old rock, found in the Heimansgroeve in South Limburg, was the oldest material in the Netherlands. New research by TNO (Netherlands Organisation for Applied Scientific Research) shows otherwise.

Geologists from the Geological Service of the Netherlands (GDN), part of TNO, have examined microscopic fossils from a 1982 borehole near Kortgene in Zeeland and now establish that the rock is even older: 420 million years.

"This is rock that is no less than six times older than the time when the dinosaurs died out due to a meteorite impact," says Sander Houben of GDN. "Under the microscope, I saw fossil remains of primitive primeval plants, which first settled on land more than 400 million years ago."

The discovery of the rock is geologically interesting, but also of social importance. Such old strata can be important for the extraction of geothermal energy.

'Small but important piece of the puzzle solved'

Comparable pieces of rock are said to have been excavated more often in France and Belgium and better researched. According to Houben, this is the first time that a piece of earth can be this well documented in the Netherlands.

In 420 million years, the rock has survived four mass extinctions, Houben continues. The geologist says that "a small but important piece of the puzzle of the Dutch subsurface" has been solved.

Geologists already assumed that in the southwest of the country, the oldest pieces of rock would be closest to the surface. The oldest piece of earth in the world is about 4.4 billion years old. That piece of rock is said to have formed 160 million years after the formation of the earth.