Title: Postdoctoral Fellow
Country/Region: China
Period: 2024/8/1-2024/10/30
Theme: Investigating the topography of discontinuities and dynamic process beneath Northwest Pacific using the OBS and dense Array
Host: Takeshi Akuhara
Introduction: Fan Yang is a Postdoctoral Researcher at the Institute of Geology and Geophysics, Chinese Academy of Sciences (IGGCAS). He recently earned his Ph.D. in Geophysics from IGGCAS in 2022. His research studies the Earth's structure around the mantle transition zone in the Northwest Pacific and the southeastern Tibet Plateau, based on receiver function, SS precursor. He is also interested in researching the lithosphere structure and mantle flow. He obtained a panoptic view of mantle flow beneath the trans-continental Northeast Asia through the SKS splitting method. His research aimed at estimating mantle compositional heterogeneity and exploring different tectonic plate recycling models, which is the key conditional to resolving the material and energy exchange between the Earth’s shallow and deep interior regions.
Research Report:
Final Report:
During a 3-month visit to the Earthquake Research Institute (ERI), I collaborated with Prof. Takeshi Akuhara on a project aimed at imaging the mantle transition zone (MTZ) structure around the Mariana Trench using receiver functions (RF) calculated with a multichannel convolution method (MCD). We began by conducting synthetic tests to evaluate the influence of the shallow water layer and low-velocity layer, both separately and in combination. These tests revealed that the shallow structure primarily affects the time window from the direct P-wave arrival at 0 s up to around 40-50 s. The MTZ signals, such as the P410s and P660s phases, theoretically arrive at approximately 45 s and 65 s, respectively. Therefore, if we can accurately identify the direct P-wave signal, we can also reliably image the deeper structure associated with these phases.
After completing the synthetic tests, we applied the MCD method to the Mariana Trench region, one of the most complex subduction zones in the northwest Pacific. We collected data from the IRIS data center, spanning from 2000 to 2024, from stations deployed around the Mariana region. The preliminary results indicate that the receiver function (RF) signals are more complex than previously confirmed by earlier studies. We plan to carefully select and analyze the data for further testing and interpretation, which will contribute to a deeper understanding of the subduction system in this region.
Additionally, I visited the Japan Meteorological Agency, arranged by Prof. Aitaro Kato, which allowed me to learn about their systems for collecting data on earthquakes, volcanoes, and weather forecasting, including typhoons. I also participated in the ERI annual summer party, where I made Chinese dumplings for all the attendees. Moreover, I joined the field trip of the Sakura Science Program, which provided a wonderful opportunity to observe active volcanoes, visit the KAGRA observatory, and study the structural geology around Toyama in western Japan.
Furthermore, I had the opportunity to meet and discuss with other ERI researchers on topics such as subduction and collision tectonics in the northwest Pacific and the Mariana Trench, as well as the application of receiver functions for OBS and island data. My interactions with visiting researchers and seminar speakers at ERI also greatly contributed to my research and career development.
Finally, I would like to express my gratitude to Yoko T and the ERI international office team for their invaluable assistance with logistics and administrative matters.
During a 3-month visit to the Earthquake Research Institute (ERI), I collaborated with Prof. Takeshi Akuhara on a project aimed at imaging the mantle transition zone (MTZ) structure around the Mariana Trench using receiver functions (RF) calculated with a multichannel convolution method (MCD). We began by conducting synthetic tests to evaluate the influence of the shallow water layer and low-velocity layer, both separately and in combination. These tests revealed that the shallow structure primarily affects the time window from the direct P-wave arrival at 0 s up to around 40-50 s. The MTZ signals, such as the P410s and P660s phases, theoretically arrive at approximately 45 s and 65 s, respectively. Therefore, if we can accurately identify the direct P-wave signal, we can also reliably image the deeper structure associated with these phases.
After completing the synthetic tests, we applied the MCD method to the Mariana Trench region, one of the most complex subduction zones in the northwest Pacific. We collected data from the IRIS data center, spanning from 2000 to 2024, from stations deployed around the Mariana region. The preliminary results indicate that the receiver function (RF) signals are more complex than previously confirmed by earlier studies. We plan to carefully select and analyze the data for further testing and interpretation, which will contribute to a deeper understanding of the subduction system in this region.
Additionally, I visited the Japan Meteorological Agency, arranged by Prof. Aitaro Kato, which allowed me to learn about their systems for collecting data on earthquakes, volcanoes, and weather forecasting, including typhoons. I also participated in the ERI annual summer party, where I made Chinese dumplings for all the attendees. Moreover, I joined the field trip of the Sakura Science Program, which provided a wonderful opportunity to observe active volcanoes, visit the KAGRA observatory, and study the structural geology around Toyama in western Japan.
Furthermore, I had the opportunity to meet and discuss with other ERI researchers on topics such as subduction and collision tectonics in the northwest Pacific and the Mariana Trench, as well as the application of receiver functions for OBS and island data. My interactions with visiting researchers and seminar speakers at ERI also greatly contributed to my research and career development.
Finally, I would like to express my gratitude to Yoko T and the ERI international office team for their invaluable assistance with logistics and administrative matters.