Unravelling the first Babbles of the Earth Inner Core History

Introduction

The existence of Earth's inner core was a major discovery almost a century ago, and since then the timing of its nucleation remains highly debated. This major event in the Earth’s history enhanced the energy necessary to maintain the magnetic field to the present day, making our planet habitable.

Importance of the Inner Core

Earth has thus escaped the fate of planets like Mars that lost its protective shield. While the community agreed to place the inner core formation at ~600 million years ago in the Ediacaran Period, new evidence of a change in the Earth’s magnetic field regime during the Mid-Paleozoic (416–332 Ma) challenges this hypothesis:

• Can we better constrain the Earth inner core history?

Project Overview

UBEICH will tackle this issue with a new kind of experimental data describing the long-term evolution of the Earth’s dynamo strength. In paleomagnetism, the conventional approaches fail to retrieve ancient magnetic signals from old rocks due to their weathering along their complex geological history.

Methodology

To this end, I will develop a promising but challenging multispecimen-single crystal paleointensity. This pioneering approach can significantly increase the number of observations by extracting the magnetic signal from the protected nanometric magnetic inclusions in silicate crystals with the multispecimen technique developed for other purposes.

Goals and Implications

By providing challenging-to-obtain but theoretically reliable data, UBEICH has the ambition to bring new light on the deep Earth history between 1.1 and 0.3 billion years by unraveling the inner core nucleation.

Expected Outcomes

Far-reaching implications beyond the Earth’s evolution and the origin of the magnetic field are expected, including:

1. New clues about the planetary core evolution of all rocky planets.
2. Understanding the relationships between thermal evolution, dynamo, and planet habitability.

This is of paramount importance at a time when amateur astronomers and scientists are discovering many new exoplanets, especially super-Earths located in the Habitable Zone of their star.