Rapid Fire
Hadean Proto Crust
- 16 Apr 2025
- 2 min read
A study by Macquarie University suggests that unique chemical signatures linked to plate tectonics (& subduction) were already present in Earth’s early crust (Hadean proto crust) before tectonic plate movements began.
- Chemical signatures are specific chemical patterns in ancient rocks that serve as indicators of plate tectonic processes..
- Traditionally, these signatures, like enriched Light Rare Earth Elements (LREEs) and specific isotopic ratios (Nd, Sr, Pb) indicated subduction.
- However, the study finds that these signatures could form without subduction, challenging the idea that these signals are exclusive to plate tectonics.
- A subduction zone is the region where subduction occurs, marked by deep ocean trenches, volcanic arcs, and earthquakes.
Hadean Proto Crust & Hadean Aeon:
- The Hadean proto crust is Earth's earliest crust, formed within the first 200 million years of the Hadean Aeon (4.6 to 4 billion years ago), a period marked by extreme heat, volcanic activity, and a partially molten surface.
- Over time, parts of the molten surface cooled and solidified, forming the first crust.
- Hadean Aeon was followed by the Archean Eon (4 to 2.5 billion years ago), marked by the formation of Earth's first stable crust, the beginning of plate tectonics, and the emergence of life.
- As the surface cooled, thick crust formed the first continents, which moved over the semi-fluid asthenosphere beneath.
| Read More: Tectonic Plates |
