Particle.news
Download on the App Store

New 'Cosmic Clock' Reads Krypton in Zircon to Date Ancient Landscapes

The PNAS study quantifies million-year surface exposure in Australian sands to reveal deep-time erosion histories.

Overview

  • An international team led by Curtin University demonstrated a technique that measures cosmogenic krypton trapped in detrital zircon by laser vaporizing thousands of grains.
  • Drill cores from ancient beach sands around the Nullarbor Plain show southern Australia eroded extremely slowly about 40 million years ago, at less than one meter per million years.
  • Krypton measurements indicate zircon-rich sands spent roughly 1.6 million years in near-surface transport and storage before burial.
  • The data capture a later shift to faster sediment movement tied to sea-level change, climate shifts and tectonics, helping explain major zircon-rich mineral sands such as Jacinth–Ambrosia.
  • The krypton–zircon archive could be applied to far older periods to inform models of landscape response and resource prediction, with broader use expected to benefit from calibration in modern settings.