Magnetotelluric evidence for highly focused mantle melting along the ultraslow-spreading Gakkel Ridge, Arctic Ocean
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View abstract on PubMed
Summary
This summary is machine-generated.Electromagnetic surveys reveal shallow mantle melting beneath Gakkel Ridge segment centers, contrasting with deep melting under magma-poor valleys. Lithospheric thickness variations critically control melt distribution in ultraslow-spreading ridges.
Area Of Science
- Geophysics
- Oceanography
- Tectonics
Background
- Ultraslow-spreading mid-ocean ridges exhibit diverse magmatism and tectonics.
- Mantle melting and melt transport processes are poorly understood.
- Lack of electromagnetic data hinders understanding of melting variations.
Purpose Of The Study
- Investigate mantle melting variations beneath the Gakkel Ridge.
- Utilize magnetotelluric methods to probe partial melt zones.
- Contrast melting beneath segment centers and segment ends.
Main Methods
- Conducted a one-dimensional magnetotelluric (MT) survey.
- Analyzed electrical resistivity variations at different depths.
- Interpreted MT data in the context of lithospheric structure.
Main Results
- Identified shallow low-resistivity zones (20-45 km) beneath segment centers, indicating partial melt.
- Observed no similar anomalies beneath magma-poor valleys, with lithosphere extending >50 km.
- Linked shallow melting to robust magma supply and thin lithosphere.
Conclusions
- Highly variable lithospheric thickness is key to regulating melting depth.
- Focused melt flow occurs towards segment centers.
- Variations in lithospheric thickness and focused melting explain heterogeneous crustal thickness on the Gakkel Ridge.
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