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1. Receiver function imaging of the 410 and 660 km discontinuities beneath the Australian continent

   https://doi.org/10.1093/gji/ggz525  

   Ba, Kailun ; Gao, Stephen S ; Liu, Kelly H ; Kong, Fansheng ; Song, Jianguo ( November 2019 , Geophysical Journal International)

   Summary To provide constraints on a number of significant controversial issues related to the structure and dynamics of the Australian continent, we utilize P-to-S receiver functions (RFs) recorded by 182 stations to map the 410 and 660 km discontinuities (d410 and d660, respectively) bordering the mantle transition zone (MTZ). The RFs are stacked in successive circular bins with a radius of 1o under a non-plane wavefront assumption. The d410 and d660 depths obtained using the 1-D IASP91 Earth model show a systematic apparent uplifting of about 15 km for both discontinuities in central and western Australia relative to eastern Australia, as the result of higher seismic wavespeeds in the upper mantle beneath the former area. After correcting the apparent depths using the Australian Seismological Reference Model, the d410 depths beneath the West Australia Craton are depressed by ∼10 km on average relative to the normal depth of 410 km, indicating a positive thermal anomaly of 100 K at the top of the MTZ which could represent a transition from a thinner than normal MTZ beneath the Indian ocean and the normal MTZ beneath central Australia. The abnormally thick MTZ beneath eastern Australia can be adequately explained by subducted cold slabs in the MTZ. A localized normal thickness of the MTZ beneath the Newer Volcanics Province provides supporting evidence of non-mantle-plume mechanism for intraplate volcanic activities in the Australian continent. 

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2. Upper mantle and mantle transition zone thermal and water content anomalies beneath NE Asia: Constraints from receiver function imaging of the 410 and 660 km discontinuities

   https://doi.org/10.1016/j.epsl.2019.116040  

   Sun, Muchen ; Gao, Stephen S. ; Liu, Kelly H. ; Fu, Xiaofei ( February 2020 , Earth and Planetary Science Letters)
3. High‐Resolution Receiver Function Imaging Across the Cascadia Subduction Zone Using a Dense Nodal Array

   https://doi.org/10.1029/2018GL079903  

   Ward, K. M. ; Lin, F. ; Schmandt, B. ( November 2018 , Geophysical Research Letters)
4. Using Fast Marching Eikonal Solver to Compute 3-D Pds Traveltime for Deep Receiver-Function Imaging

   https://doi.org/10.1029/2018JB015892  

   Guan, Zhe ; Niu, Fenglin ( October 2018 , Journal of Geophysical Research: Solid Earth)
5. Slab Dehydration and Mantle Upwelling in the Vicinity of the Sumatra Subduction Zone: Evidence from Receiver Function Imaging of Mantle Transition Zone Discontinuities

   https://doi.org/10.1029/2020JB019381  

   Kong, Fansheng ; Gao, Stephen S. ; Liu, Kelly H. ; Ding, Weiwei ; Li, Jiabiao ( September 2020 , Journal of Geophysical Research: Solid Earth)

   A total of 10,586P‐to‐Sradial receiver functions recorded by 64 broadband seismic stations were utilized to image the 410 and 660 km discontinuities (d410 and d660, respectively) bordering the mantle transition zone (MTZ) beneath the Sumatra Island, the Malay Peninsula, and the western margin of the South China Sea. The d410 and d660 were imaged by stacking receiver functions in successive circular bins with a radius of 1°, after moveout corrections based on the 1‐D IASP91 Earth model. The resulting apparent depths of the discontinuities exhibit significant and spatially systematic variations. The apparent depths of the d410 and d660 range from 382 to 459 km and 637 to 700 km with an average of 406 ± 13 and 670± 12 km, respectively, while the corresponding values for the MTZ thickness are 217 to 295 km and 261 ± 13 km. Underneath southern Sumatra and adjacent regions, the MTZ is characterized by an uplifted d410 and a depressed d660. While the former is probably caused by the low temperature anomaly, the latter is most likely related to a combination of the low temperature anomaly and dehydration associated with the subducted Australian Plate that has reached at least the d660. In contrast, an abnormally thin MTZ is imaged to the southwest of the Toba Caldera. This observation, when combined with results from previous seismic tomography studies, can be explained by advective thermal upwelling through a slab window.

    

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