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Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Missouri University of Science and Technology

Geophysics and Seismology

Decompression Melting

Publication Year

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Continental Break-Up Under A Convergent Setting: Insights From P Wave Radial Anisotropy Tomography Of The Woodlark Rift In Papua New Guinea, Youqiang Yu, Frederik Tilmann, Dapeng Zhao, Stephen S. Gao, Kelly H. Liu Mar 2022

Continental Break-Up Under A Convergent Setting: Insights From P Wave Radial Anisotropy Tomography Of The Woodlark Rift In Papua New Guinea, Youqiang Yu, Frederik Tilmann, Dapeng Zhao, Stephen S. Gao, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To explore the dynamic mechanism of continental rifting within a convergent setting, we determine the first P wave radial anisotropic tomography beneath the Woodlark rift in southeastern Papua New Guinea, which develops within the obliquely colliding zone between the Australian and southwest Pacific plates. The rift zone is depicted as localized low-velocity anomalies with positive radial anisotropy, which rules out a dominant role of active mantle upwelling in promoting the rift development and favors passive rifting with decompression melting as main processes. Downwelling slab relics in the upper mantle bounding the rift zone are revealed based on observed high-velocity anomalies …


Mantle Structure And Flow Beneath An Early-Stage Continental Rift: Constraints From P Wave Anisotropic Tomography, Youqiang Yu, Stephen S. Gao, Dapeng Zhao, Kelly H. Liu Feb 2020

Mantle Structure And Flow Beneath An Early-Stage Continental Rift: Constraints From P Wave Anisotropic Tomography, Youqiang Yu, Stephen S. Gao, Dapeng Zhao, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To explore 3-D seismic velocity and radial anisotropy structures of the upper mantle and mantle transition zone beneath the Malawi and Luangwa rift zones of the East African Rift System, we conduct the first study of P wave anisotropic tomography using data recorded at 75 seismic stations including 34 stations that we installed along two profiles as part of the Seismic Arrays for African Rift Initiation experiment. Both rift zones are revealed to have normal or slightly low velocity anomalies in the lithosphere and upper asthenosphere. The surrounding cratonic lithosphere is characterized by high-velocity anomalies with amplitudes ranging from +1.0% …