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Title: Longest continuously erupting large igneous province driven by plume-ridge interaction
Abstract Large igneous provinces (LIPs) typically form in one short pulse of ∼1–5 Ma or several punctuated ∼1–5 Ma pulses. Here, our 25 new 40Ar/39Ar plateau ages for the main construct of the Kerguelen LIP—the Cretaceous Southern and Central Kerguelen Plateau, Elan Bank, and Broken Ridge—show continuous volcanic activity from ca. 122 to 90 Ma, a long lifespan of >32 Ma. This suggests that the Kerguelen LIP records the longest, continuous high-magma-flux emplacement interval of any LIP. Distinct from both short-lived and multiple-pulsed LIPs, we propose that Kerguelen is a different type of LIP that formed through long-term interactions between a mantle plume and mid-ocean ridge, which is enabled by multiple ridge jumps, slow spreading, and migration of the ridge. Such processes allow the transport of magma products away from the eruption center and result in long-lived, continuous magmatic activity.  more » « less
Award ID(s):
1643713
PAR ID:
10219586
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Geology
Volume:
49
Issue:
2
ISSN:
0091-7613
Page Range / eLocation ID:
206 to 210
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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