Mineral discovery points to ancient meteorite impacts

[David Entwistle]

From Curtin University news site.

A team of Curtin University geoscientists has discovered the earliest known occurrence of reidite, one of Earth’s rarest minerals. At 1.2 billion years, the finding is more than double the age of the previous oldest known occurrence at 450 million years.

Working with the University of St Andrews, the team, led by Professor Steven Reddy from the Institute for Geoscience Research (TIGeR) at Curtin’s Western Australian School of Mines, discovered the reidite in shocked zircon from impact ejecta at Stac Fada in Scotland. He said reidite is important because it is only known to form in nature during meteorite impact events.

The abstract is here.

[David Entwistle]

Steven Reddy, Professor of Geology and Geoscience Atom Probe Science Leader, Curtin University, provides an easily digested summary of this research here for The Conversation.

A new discovery of an extremely rare mineral, called reidite, from a layer of rock in the North West Highlands of Scotland may seem utterly insignificant on first glance. But this occurrence of reidite has major implications for understanding the early evolution of our solar system.

To comprehend the significance of these small specs of reidite, we must first consider the moon.

The most obvious features on the moon’s surface are the circular craters formed by countless meteorite impacts. The dating of lunar samples collected during the Apollo missions tells us that many of these impacts formed around 3.9 billion years ago, which was relatively early in the evolution of our 4.6 billion year old solar system...