Seismic anisotropy from teleseismic shear wave splitting measurements

Seismic anisotropy in the Fujian lithosphere and its tectonic implications from teleseismic shear wave splitting measurements

  1. As a result, the thickness of anisotropic layer increases from northeast to southwestin the Fujian area and in the southern part.

  2. Compared with the global tomography, it can be explained that the variations of fast-polarizations could relate to the EW mantle flowcreated by NS collision between the India and Eurasian Plates.

鍾仁齊 Jen-Chi Chung
碩士論文:利用剪力波分離探討福建地區岩石圈的非均向性及其地體構造上之意涵
Master’s Thesis: Seismic anisotropy in the Fujian lithosphere and its tectonic implications from teleseismic shear wave splitting measurements

Improving the seismic imaging by using multiple attenuation methods

Improving the seismic imaging in the southern Ryukyu subduction system by using multiple attenuation methods

  1. In this study, we test two sets of multiple attenuation methods: differentiate the physical properties and modeling multiples from sea bed and signal.

  2. We end up using the flow: surface related multiple elimination(SRME), Radon transform, dip-filter and deconvolution.

呂奇祝 Ci-Jhu Lyu
碩士論文:利用複反射衰減方法提高海上震測成像並探討南琉球隱沒系統
Master’s Thesis: Improving the seismic imaging in the southern Ryukyu subduction system by using multiple attenuation methods

Fault Investigation Using Shallow Seismic Survey

Yuli Fault Investigation Using Shallow Seismic Survey

  1. In this study, we combine two types of active source for fault imaging: Minivibe and weight drop.

  2. The reflection signal from weight drop can be recovered is 700 m and from Minivibe is around  2000 m.

  3. We can clearly see the Yuli fault dipping to the east.

計畫名稱:
104年度重要活動斷層構造特性調查二期─活動斷層近地表構造特性調查(1/4)
Study of the Near Surface Structure of Active Fault (1/4)

相關文章:台灣活動斷層淺部構造的地球物理調查

Three-dimensional Vp, Vs, and Vp/Vs seismic velocity structures in the Wuyi-Yunkai orogen

Three-dimensional Vp, Vs, and Vp/Vs seismic velocity structures in the Wuyi-Yunkai orogen

  1. Tomographic Inversion with the data of the active- and passive- sources to better constrain the shallow structure.

  2. Low Vp/Vs ratios of the crust in most of Fujian area suggest the felsic crust.

  3. The shallower crust along the coastline results in high heat flow.

Cai, H.-T., H. Kuo-Chen, X. Jin, C.-Y. Wang, B.-S. Huang, H.-Y. Yen (2015) A three-dimensional Vp, Vs and Vp/Vs crustal structure in Fujian, Southeast China, from active and passive source experiments, J. Asian Earth Sci., doi: 10.1016/j.jseaes.2015.06.014

Monitoring micro-earthquakes in active faults from dense seismic arrays

Monitoring micro-earthquakes in active faults from dense seismic arrays

  1. Microearthquakes were recorded by a dense seismic array near the Lishan fault of Taiwan.

  2. The Lishan fault is a high-angle left-lateral structure based on seismicity and focal mechanisms.

  3. The Lishan fault is an active structure from the surface to about 35 km.

Kuo-Chen, H., F. Wu, W.-L. Chang, C.-Y. Chang, C.-Y. Cheng, N. Hirata (2015) Is the Lishan Fault of Taiwan Active?, Tectonophysics, doi: 10.1016/j.tecto.2015.09.002.

Reflected and refracted seismic profiles in Taiwan and southeastern China

Reflected and refracted seismic profiles in Taiwan and southeastern China

  1. Crustal structures are imaged by active-source experiments.

  2. We used both refracted and reflected phases to model the crustal structures.

  3. The crustal evolution involved the closed rift basin in Fujian and Taiwan orogen.

Kuo, Y.W., C.Y. Wang, H. Kuo-Chen *, X. Jin, H.T. Cai, J.Y. Lin, F.T. Wu, H.Y. Yen, B.S. Huang, W.T. Liang, D. Okaya, and L. Brown (2015)  Crustal structures from the Wuyi-Yunkai orogen to the Taiwan orogen: the onshore-offshore wide-angle seismic experiments of the TAIGER and ATSEE projects, Tectonophysics, doi: 10.1016/j.tecto.2015.09.014.

Seismic anisotropy from teleseismic shear wave splitting measurements

Seismic anisotropy in the southeastern China and its tectonic implications from teleseismic shear wave splitting measurements

  1. In this study, we use teleseismic SKS/SKKS splitting as a tool for investigating seismic anisotropy.

  2. As a result, along the Fujian coastline,compared with the global tomography, it can be explained that the variations of fast-­‐polarizations (φf) could relate to the EW mantle flow created by NS collision between the India and Eurasian Plates, influenced by the Taiwan orogen (the collision between Eurasian and Philippine sea plates) and two subduction systems (the Manila and Ryukyu subductions).

彭筱涓 Hsiao-Chuan Peng
碩士論文:利用剪力波分離探討中國大陸東南沿海地區的非均向及其地體構造上之意涵
Master’s Thesis: Seismic anisotropy in the southeastern China and its tectonic implications from teleseismic shear wave splitting measurements

Seismic anisotropy in the upper crust from active source experiment

Seismic anisotropy in the upper crust from active source experiment

  1. Seismic anisotropy obtained from active source experiment

  2. Two anisotropic patterns in the Central Range. In the northern part, fast direction 42° with 9.7% anisotropy. In the southern part: fast direction 18° with 5.8% anisotropy.

  3. The deformation of the upper crust in the Central Range in northern part higher than that in the southern part.

Kuo-Chen, H., P. Sroda, F. T. Wu, C.-Y. Wang, Y.W. Kuo (2013) Seismic anisotropy of the upper crust in the mountain ranges of Taiwan from the TAIGER explosion experiment, Terrestrial, Atmospheric and Oceanic Sciences, 24, 6, 963-970, doi: 10.3319/TAO.2013.07.30.01(T).

Seismic velocity structures in the Taiwan orogen

Seismic velocity structures in the Taiwan orogen

  1. Seismic velocity structures from the independent data sets of the TAIGER and other projects (over 2,500 temporary seismic stations used in the study)

  2. Tomographic Inversion with the data of the active- and passive- sources to better constrain the shallow structure.

  3. Two crustal roots observed beneath the Central and Coastal Ranges due to the collision between the two plates.

Kuo-Chen, H., F. T. Wu, and S. W. Roecker (2012) Three-Dimensional P Velocity Structures of the Lithosphere Beneath Taiwan from the Analysis of TAIGER and Related Seismic Data sets, JGR, doi: 10.1029/2011JB009108.

Wu, F. T., and H. Kuo-Chen, K. McIntosh (2014) Subsurface imaging, TAIGER experiments and tectonic models of Taiwan, J. Asian Earth Sci., doi: 10.1016/j.jseaes.2014.03.024. (Review paper)

Physical properties of the upper crust in the Central Range of Taiwan

Physical properties of the upper crust in the Central Range of Taiwan

  1. Felsic crust in the Central Range based on Vp/Vs tomography

  2. Hot and dry continental crust beneath the Central Range

  3. Geothermal gradient ~ 30°C/km beneath the Central Range

Kuo-Chen, H., F. Wu, D.M. Jenkins, J. Mechie, S. Roecker, C.-Y. Wang, and B.-S.Huang (2012) Seismic evidence for the α-β quartz transition beneath Taiwan from Vp/Vs tomography, Geophys. Res. Lett., doi: 10.1029/2012GL053649