Details

Autor(en) / Beteiligte

• Huang, Wentao
• Tarduno, John A
• Zhou, Tinghong
• Ibañez-Mejia, Mauricio
• Dal Olmo-Barbosa, Laércio
• Koester, Edinei
• Blackman, Eric G
• Smirnov, Aleksey V
• Ahrendt, Gabriel
• Cottrell, Rory D
• Kodama, Kenneth P
• Bono, Richard K
• Sibeck, David G
• Li, Yong-Xiang
• Nimmo, Francis
• Xiao, Shuhai
• Watkeys, Michael K

Titel

Near-collapse of the geomagnetic field may have contributed to atmospheric oxygenation and animal radiation in the Ediacaran Period

Ist Teil von

• Communications earth & environment, 2024-12, Vol.5 (1), p.207-8

Ort / Verlag

London: Nature Publishing Group

Erscheinungsjahr

2024

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Earth’s magnetic field was in a highly unusual state when macroscopic animals of the Ediacara Fauna diversified and thrived. Any connection between these events is tantalizing but unclear. Here, we present single crystal paleointensity data from 2054 and 591 Ma pyroxenites and gabbros that define a dramatic intensity decline, from a strong Proterozoic field like that of today, to an Ediacaran value 30 times weaker. The latter is the weakest time-averaged value known to date and together with other robust paleointensity estimates indicate that Ediacaran ultra-low field strengths lasted for at least 26 million years. This interval of ultra-weak magnetic fields overlaps temporally with atmospheric and oceanic oxygenation inferred from numerous geochemical proxies. This concurrence raises the question of whether enhanced H ion loss in a reduced magnetic field contributed to the oxygenation, ultimately allowing diversification of macroscopic and mobile animals of the Ediacara Fauna.An ultra-weak magnetic field from Earth’s core lasting for at least 26 million years may have contributed to Earth’s oxygenation and further diversification of the Ediacaran fauna, according to single-crystal paleointensity data from igneous rocks in South Africa and Brazil.