Palaeomagnetic field intensity variations suggest Mesoproterozoic inner-core nucleation

@article{Biggin2015PalaeomagneticFI,
  title={Palaeomagnetic field intensity variations suggest Mesoproterozoic inner-core nucleation},
  author={Andrew J. Biggin and Elisa J. Piispa and Lauri J. Pesonen and Richard Holme and Greig A. Paterson and Toni Veikkolainen and Lisa Tauxe},
  journal={Nature},
  year={2015},
  volume={526},
  pages={245-248}
}
The Earth’s inner core grows by the freezing of liquid iron at its surface. The point in history at which this process initiated marks a step-change in the thermal evolution of the planet. Recent computational and experimental studies have presented radically differing estimates of the thermal conductivity of the Earth’s core, resulting in estimates of the timing of inner-core nucleation ranging from less than half a billion to nearly two billion years ago. Recent inner-core nucleation (high… 
First palaeointensity data from the cryogenian and their potential implications for inner core nucleation age
The timing of inner core nucleation is a hugely significant event in Earth's evolution and has been the subject of intense debate. Some of the most recent theoretical estimates for the age of
The signature of inner-core nucleation on the geodynamo
Abstract Energy considerations indicate that the power delivered to the present-day geodynamo comes mainly from the growth of the solid inner core, through light element and latent heat releases. The
Powering Earth’s dynamo with magnesium precipitation from the core
TLDR
It is shown that the precipitation of magnesium-bearing minerals from the core could have served as an alternative power source and that Earth’s dynamo would survive throughout geologic time even if core radiogenic heating were minimal and core cooling were slow.
Palaeointensity of the 1.3 billion-yr-old Gardar basalts, southern Greenland revisited: no evidence for onset of inner core growth
The age of the inner core nucleation is a first-order problem in the thermal evolution of the Earth that can be addressed with palaeomagnetism. We conducted a palaeointensity study on the 1.3 Ga
Young inner core inferred from Ediacaran ultra-low geomagnetic field intensity
An enduring mystery about Earth has been the age of its solid inner core. Plausible yet contrasting core thermal conductivity values lead to inner core growth initiation ages that span 2 billion
Simulating 2 Ga of geodynamo history
The paleomagnetic record indicates the geodynamo has been active over much of Earth history with surprisingly little trend in paleointensity. Variability, however, is expected from models that
Thermal evolution of Earth with magnesium precipitation in the core
Vigorous convection in Earth's core powers our global magnetic field, which has survived for over three billion years. In this study, we calculate the rate of entropy production available to drive
Pallasite paleomagnetism: Quiescence of a core dynamo
Recent paleomagnetic studies of two Main Group pallasites, the Imilac and Esquel, have found evidence for a strong, late-stage magnetic field on the parent body. It has been hypothesized that this
The Fate of Liquids Trapped During the Earth's Inner Core Growth
The growth history of the inner core is inherently linked to the thermal history of the Earth. The crystallization of the inner core may have been delayed by supercooling, and went through an initial
The deep Earth may not be cooling down
Abstract The Earth is a thermal engine generating the fundamental processes of geomagnetic field, plate tectonics and volcanism. Large amounts of heat are permanently lost at the surface yielding the
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