Deep mantle plumes feeding periodic alignments of asthenospheric fingers beneath the central and southern Atlantic Ocean
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View abstract on PubMed
Summary
This summary is machine-generated.Seismic tomography reveals asthenospheric "fingers" beneath the Atlantic. These channels connect to distinct mantle plumes, influencing hotspots and mid-ocean ridge basalts with unique isotopic signatures.
Area Of Science
- Geophysics
- Seismology
- Mantle Dynamics
Background
- Asthenospheric flow influences plate tectonics and surface geology.
- Understanding mantle plume structure and interaction is crucial for Earth science.
- Previous studies suggested large-scale structures but lacked detailed resolution.
Purpose Of The Study
- To investigate the fine structure of the asthenosphere beneath the South and Central Atlantic Ocean.
- To identify and characterize low shear velocity channels and their relationship to mantle plumes.
- To explore the interaction between deep mantle plumes and upper mantle circulation.
Main Methods
- High-resolution full waveform seismic tomography.
- Analysis of seismic velocity anomalies in the Earth's mantle.
- Correlation with seafloor depth anomalies and geochemical data (isotopic signatures).
Main Results
- Identified distinct asthenospheric low shear velocity channels (
- fingers
- ) parallel to plate motion.
- Each finger on the African plate links to separate whole mantle plume groups originating at the core-mantle boundary.
- Plumes merge in the lower mantle and interact with upper mantle circulation, influencing hotspot locations and mid-ocean ridge basalt compositions.
Conclusions
- The African Large Low Shear Velocity Province is a collection of distinct mantle plumes, not a uniform structure.
- Upper mantle processes significantly influence plume behavior and geochemical signatures.
- Channeled mantle flow plays a key role in shaping features like hotspots and mid-ocean ridge volcanism.
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