Longest continuously erupting large igneous province driven by plume-ridge interaction
Longest continuously erupting large igneous province driven by plume-ridge interaction
Geology (Boulder) (October 2020) 49 (2): 206-210
- absolute age
- Ar/Ar
- basalts
- Broken Ridge
- Cretaceous
- dates
- emplacement
- igneous rocks
- Indian Ocean
- Kerguelen Plateau
- large igneous provinces
- Leg 119
- Leg 120
- Leg 183
- magmas
- mantle plumes
- Mesozoic
- mid-ocean ridges
- Ocean Drilling Program
- ocean floors
- ODP Site 738
- ODP Site 747
- ODP Site 748
- ODP Site 749
- ODP Site 750
- ODP Site 1136
- ODP Site 1137
- ODP Site 1138
- ODP Site 1141
- ODP Site 1142
- Southern Ocean
- volcanic rocks
- volcanism
- ELT 46
Large igneous provinces (LIPs) typically form in one short pulse of approximately 1-5 Ma or several punctuated approximately 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.