Interseismic Deformation of the Chegualin Fault Derived From Geodetic Data Between 2016 and 2019

Abstract

Geodetic data containing 15 dual-frequency continuous GNSS (cGNSS) stations 2 single-frequency cGNSS stations 69 dual-frequency survey-mode GNSS stations 293 leveling benchmarks 13 traverse points and 119 structure points from May 2016 to December 2019 were collected and analyzed to understand the characteristics of westward extended lineament of the Chegualin Fault Horizontal velocity field relative to S01R station in the north side of the lineament is approximately 48-50 mm/yr in N269° while it is approximately 50-60 mm/yr in N269° in the south side An obvious velocity difference of 10 mm/yr is shown across the lineament The subsidence rates in the north side of lineament are approximately 8-10 mm/yr while the subsidence rate is approximately 6-8 mm/yr in the south Relative to the northern side southern side raises in approximately 1-3 mm/yr An arc-tangent pattern is clearly shown across the lineament according to the analysis of velocity profiles in fault-parallel component indicating a right-lateral shearing on the lineament The optimal fault parameters from the 2D block model show that the lineament is a high dip-angle of 76-81° right-lateral strike-slip fault The locking depth merely ranges 0 01-0 11 km The slip rate is approximately 0 3-0 8 mm/yr while the long-term slip rate is approximately 6 3-9 9 mm/yr In this study vertical velocities cannot be modeled by 2D block model in the same time It is speculated that the surface deformation in this study area is not totally dominated by fault activity but also influenced by mud diapirism

Date of Award	2020
Original language	English
Supervisor	Kuo-En Ching (Supervisor)