Search research articles

Search research articles

Related Experiment Videos

Sharp sides to the African superplume.

Sidao Ni¹, Eh Tan, Michael Gurnis

¹Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125, USA. stone@gps.caltech.edu

Science (New York, N.Y.)

|June 8, 2002

Summary

This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Identifying dehydration-induced shear velocity anomaly in the Earth's core-mantle boundary.

Innovation (Cambridge (Mass.))·2025

Same author

Rapid shear zone weakening during subduction initiation.

Proceedings of the National Academy of Sciences of the United States of America·2024

Same author

Mountain building process of the Taiwan orogeny.

Science advances·2024

Same author

Constraining Earth's nonlinear mantle viscosity using plate-boundary resolving global inversions.

Proceedings of the National Academy of Sciences of the United States of America·2024

Same author

Small-scale layered structures at the inner core boundary.

Nature communications·2023

Same author

Compositional and thermal state of the lower mantle from joint 3D inversion with seismic tomography and mineral elasticity.

Proceedings of the National Academy of Sciences of the United States of America·2023

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

A massive deep-earth structure beneath southern Africa shows a sharp, tilted boundary. This suggests a dense chemical layer within an upwardly flowing thermal plume, indicating dynamic instability.

Area of Science:

Geophysics
Seismology
Earth Sciences

Background:

A large, anomalous structure exists beneath southern Africa, originating from the core-mantle boundary.
This structure is approximately 1200 km across and extends 1500 km upward.
It exhibits a shear velocity reduction of about 3%.

Purpose of the Study:

To precisely characterize the structure and boundaries of the deep-earth anomaly beneath southern Africa.
To investigate the dynamic processes and composition of this large-scale geological feature.
To understand the implications of the anomaly's structure for mantle dynamics.

Main Methods:

Analysis of SKS seismic phases traversing the eastern side of the anomaly.
Detailed seismic velocity analysis to determine structural boundaries.

Related Experiment Videos

Development and testing of dynamic models constrained by seismic data.

Main Results:

The anomaly's eastern boundary is sharp, with a width less than 50 km.
The boundary exhibits an outward tilt from the structure's center.
Dynamic models indicate a dense chemical layer within an upwardly flowing thermal structure.

Conclusions:

The sharp, tilted boundary suggests dynamic instability of the deep-earth structure on geological timescales.
The findings support models involving dense chemical layers interacting with thermal plumes.
This research provides new insights into the complex dynamics at the core-mantle boundary.