Phanerozoic continental magmatism: Linking spatiotemporal evolution, isotopic composition, and chemical weathering
Journal
Earth and Planetary Science Letters
Journal Volume
684
Start Page
119975
ISSN
0012-821X
Date Issued
2026-06
Author(s)
Abstract
Chemical weathering plays a critical role in regulating Earth’s long-term climate and supplying key nutrients to the biosphere. Weathering of tectonically active continental magmatic belts contribute significantly to the magnitude and composition of the global weathering flux; however, their contribution remains poorly quantified. To address this gap, we integrate isotopic data within their reconstructed paleogeographic and paleoclimatic contexts to estimate the global chemical weathering flux and its associated isotopic composition. Our results reveal that the abundance, distribution, and isotopic signatures of magmatic belts are systematically linked to the supercontinent cycle. The magnitude of chemical weathering flux is governed by the interplay between paleogeography and paleoclimate. We show that the global isotopic flux from magmatic belts exhibits a strong statistical correlation with seawater 87Sr/86Sr variations, suggesting that the weathering of continental magmatic belts dominates the marine isotope composition. Our study provides an interpretable framework that connects the evolution of supercontinent cycles with surface processes and long-term climate regulation, offering new insights into the coupled dynamics of Earth’s deep and surface systems.
Subjects
Chemical weathering
Continental magmatism
Long-term carbon cycle
Plate reconstructions
Seawater Sr isotopes
Publisher
Elsevier BV
Type
journal article