Plate tectonics and mantle plumes are two of the most fundamental solid-Earth processes that have operated through much of Earth history. For the past 300 million years, mantle plumes are known to derive mostly from two large low shear velocity provinces (LLSVPs) above the core-mantle boundary, referred to as the African and Pacific superplumes, but their possible connection with plate tectonics is debated. Here, we demonstrate that transition elements (Ni, Cr, and Fe/Mn) in basaltic rocks can be used to trace plume-related magmatism through Earth history. Our analysis indicates the presence of a direct relationship between the intensity of plume magmatism and the supercontinent cycle, suggesting a possible dynamic coupling between supercontinent and superplume events. In addition, our analysis shows a consistent sudden drop in MgO, Ni and Cr at ~3.2-3.0 billion years ago, possibly indicating an abrupt change in mantle temperature at the start of global plate tectonics.
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http://dx.doi.org/10.1038/s41467-019-13300-4 | DOI Listing |
Open Res Eur
December 2024
Geosciences, Universitetet i Oslo Institutt for geofag, Oslo, Oslo, 0371, Norway.
Background: Despite extensive studies of the Mesozoic-Cenozoic magmatic history of Svalbard, little has been done on the Paleozoic magmatism due to fewer available outcrops.
Methods: 2D seismic reflection data were used to study magmatic intrusions in the subsurface of eastern Svalbard.
Results: This work presents seismic evidence for west-dipping, Middle Devonian-Mississippian sills in eastern Spitsbergen, Svalbard.
Ecol Evol
January 2025
Instituto Milenio de Oceanografía (IMO) Universidad de Concepción Concepción Chile.
Mechanisms driving the spatial and temporal patterns of species distribution in the Earth's largest habitat, the deep ocean, remain largely enigmatic. The late Miocene to the Pliocene (~23-2.58 Ma) is a period that was marked by significant geological, climatic, and oceanographic changes.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Earth Science, University of Bergen, Bergen, Norway.
Plate tectonics predicts that mountain ranges form by tectono-magmatic processes at plate boundaries, but high topography is often observed along passive margins far from any plate boundary. The high topography of the Scandes range at the Atlantic coast of Fennoscandia is traditionally assumed isostatically supported by variation in crustal density and thickness. Here we demonstrate, by our Silverroad seismic profile, that the constantly ~44 km thick crust instead is homogenous above the Moho, and Pn-velocity abruptly change from 7.
View Article and Find Full Text PDFA key question in the planetary sciences centers on the divergence between the sibling planets, Venus and Earth. Venus currently does not operate with plate tectonics, and its thick atmosphere has led to extreme greenhouse conditions. It is unknown if this state was set primordially or if Venus was once more Earth-like.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
School of GeoSciences, University of Edinburgh, Edinburgh EH9 3FE, United Kingdom.
The Red Planet is a magnetic planet. The Martian crust contains strong magnetization from a core dynamo that likely was active during the Noachian period when the surface may have been habitable. The evolution of the dynamo may have played a central role in the evolution of the early atmosphere and the planet's transition to the current cold and dry state.
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