Estimation of local site effects in Ojiya city using aftershock records of the 2004 Mid Niigata Prefecture earthquake and microtremors
スポンサーリンク
概要
- 論文の詳細を見る
Aftershock observations of the 2004 Mid Niigata Prefecture earthquake were conducted in the central part of Ojiya city, the Niigata prefecture, central Japan, to investigate local site effects. We installed eight accelerographs in the vicinity of the K-NET and JMA stations in the area. The stations of the aftershock observations are situated under different geological conditions including one installed in a mountainous area on Tertiary layers to serve as a reference site. We examined the ground-motion characteristics of the records for a Mj 6.1 aftershock focusing on local site effects. The amplification, at a period of less than 1 sec, is the largest in the vicinity of the K-NET station. The amplification at periods longer than 2 sec is larger in the western part of the city than those in the east. We estimated the <I>S</I>-wave velocity structure in the sediments above the basement with an <I>S</I>-wave velocity of 3.4 km/sec from the inversion of phase velocities measured by the array observations of vertical microtremors. We discuss the amplification factors using the <I>S</I>-wave velocity profile and show that shallow soils over the layer with an <I>S</I>-wave velocity of 0.49 km/sec are responsible for the amplification at periods shorter than 0.4 sec. Deeper sedimentary layers are needed to explain amplification at periods of 1 sec.
- 公益社団法人 日本地震学会、地球電磁気・地球惑星圏学会 、特定非営利活動法人 日本火山学会、日本測地学会、日本惑星科学会の論文
著者
-
ASANO Kimiyuki
Disaster Prevention Research Institute, Kyoto University
-
TAKAHASHI Toshiyuki
Tokyo Soil Research
-
YAMADA Nobuyuki
Disaster Prevention Research Institute, Kyoto University
-
Motoki Kentaro
Interdisciplinary Graduate School Of Science And Engineering Tokyo Institute Of Technology
-
Yamanaka Hiroaki
Interdisciplinary Graduate School Of Science And Engineering Tokyo Institute Of Technology
関連論文
- Source process and near-source ground motions of the 2005 West Off Fukuoka Prefecture earthquake
- Estimation of local site effects in Ojiya city using aftershock records of the 2004 Mid Niigata Prefecture earthquake and microtremors
- Estimation of the source model for the foreshock of the 2004 off the Kii peninsula earthquakes and strong ground motion simulation of the hypothetical Tonankai earthquake using the empirical Green's function method
- Source characteristics of shallow intraslab earthquakes derived from strong-motion simulations
- Estimation of the source model for the foreshock of the 2004 off the Kii peninsula earthquakes and strong ground motion simulation of the hypothetical Tonankai earthquake using the empirical Green's function method
- Estimation of the source model for the foreshock of the 2004 off the Kii peninsula earthquakes and strong ground motion simulation of the hypothetical Tonankai earthquake using the empirical Green's function method
- Characteristics of Weak Earthquake Ground Motions in the Sumiyoshi Area of Kobe
- Observation of aftershocks of the 2003 Tokachi-Oki earthquake for estimation of local site effects
- Observation of ground motions of aftershocks of the 2007 Noto Hanto earthquake in Monzenmachi, the Wajima city, for estimation of site amplification
- Long-period ground motion simulation in the Kinki area during the M_J 7.1 foreshock of the 2004 off the Kii peninsula earthquakes
- Source process and near-source ground motions of the 2005West Off Fukuoka Prefecture earthquake
- Estimation of local site effects in Ojiya city using aftershock records of the 2004 Mid Niigata Prefecture earthquake and microtremors
- Source model for strong ground motion generation in the frequency range 0.1-10Hz during the 2011 Tohoku earthquake