TY - JOUR

T1 - A study on the compatibility of 3-D seismic velocity structures with gravity data of Taiwan

AU - Yen, Horng Yuan

AU - Hsieh, Hsien Hsiang

PY - 2010/12

Y1 - 2010/12

N2 - The Bouguer anomaly of Taiwan has been revised in this study based on more accurate terrain data provided by the Taiwanese Digital Terrain Model compiled by the Taiwan Forestry Bureau. Three seismic velocity models, those determined by Rau and Wu (1995), Kim et al. (2005), and Wu et al. (2007) respectively, were selected for our study. We converted their velocity models to density models using the relationship between P-wave velocity and rock density proposed by Ludwig et al. (1970) and Barton (1986), and then calculated their corresponding gravity anomalies. According to the correlation coefficient between the Bouguer anomalies calculated from the velocity models and the revised Bouguer anomalies, the Kim et al. model was more compatible with gravity data than the other two velocity models. The differences between the revised gravity anomaly and the calculated gravity anomalies trend toward positive values at elevations higher than 2000 m. This indicates that the velocities at the shallower depths beneath the mountainous area of the three models are overdetermined, i.e., higher than the real velocities. This ratiocination implies that the crustal thickness beneath the Central Range is less than 55 km which was obtained from the velocity models.

AB - The Bouguer anomaly of Taiwan has been revised in this study based on more accurate terrain data provided by the Taiwanese Digital Terrain Model compiled by the Taiwan Forestry Bureau. Three seismic velocity models, those determined by Rau and Wu (1995), Kim et al. (2005), and Wu et al. (2007) respectively, were selected for our study. We converted their velocity models to density models using the relationship between P-wave velocity and rock density proposed by Ludwig et al. (1970) and Barton (1986), and then calculated their corresponding gravity anomalies. According to the correlation coefficient between the Bouguer anomalies calculated from the velocity models and the revised Bouguer anomalies, the Kim et al. model was more compatible with gravity data than the other two velocity models. The differences between the revised gravity anomaly and the calculated gravity anomalies trend toward positive values at elevations higher than 2000 m. This indicates that the velocities at the shallower depths beneath the mountainous area of the three models are overdetermined, i.e., higher than the real velocities. This ratiocination implies that the crustal thickness beneath the Central Range is less than 55 km which was obtained from the velocity models.

KW - Bouguer gravity anomaly

KW - Crustal thickness

KW - Moho depth

KW - Seismic velocity structures

UR - http://www.scopus.com/inward/record.url?scp=78651298537&partnerID=8YFLogxK

U2 - 10.3319/TAO.2010.03.03.01(T)

DO - 10.3319/TAO.2010.03.03.01(T)

M3 - 期刊論文

AN - SCOPUS:78651298537

SN - 1017-0839

VL - 21

SP - 897

EP - 904

JO - Terrestrial, Atmospheric and Oceanic Sciences

JF - Terrestrial, Atmospheric and Oceanic Sciences

IS - 6

ER -