2014年長野県北部の地震の被害調査と震源のモデル化  [in Japanese] DAMAGE INVESTIGATION AND SOURCE CHARACTERIZATION OF THE 2014 NORTHERN PART OF NAGANO PREFECTURE EARTHQUAKE  [in Japanese]

Access this Article

Author(s)

Abstract

2014年長野県北部の地震は震源深さが浅い内陸地殻内地震であり震源近傍域に強震動を引き起こすとともに,起震断層と考えられる糸魚川-静岡構造線を構成する神城断層に沿って地表地震断層が確認された.地震発生直後に地震被害調査を行い震源近傍域で強震動と断層変位に伴う地盤変形に起因すると考えられる構造物の被害を確認した.また経験的グリーン関数法を用いたフォワードモデリングにより震源モデルを推定した.その結果,断層面上にやや大きめの一つの強震動生成域を設置することにより震源近傍の観測記録を再現できることがわかった.また,本地震の震源モデルの地震モーメントと短周期レベルの関係は既往のスケーリング則で表現できることなどが明らかにされた.

 The 2014 northern part of Nagano prefecture earthquake of Mj6.7 revealed earthquake fault on the surface along the Kamishiro fault. Strong ground motions were generated near source area and caused severe damage to many houses. Authors performed damage investigation around source area in the aftermath of the earthquake. We confirmed a trace of the earthquake damage due to strong ground motion and ground displacement. We constructed a preliminary source model by the empirical Green's function method. The source parameters for strong motion generation area located on the fault plane were determined from the comparisons of the synthesized broad-band ground motions with the observed ones at several stations including near source. Resultantly, we proposed source model with one strong motion generation area located at near hypocenter. The relationship between seismic moment and short period level of acceleration source spectrum of this earthquake are expressed in a scaling law of the past study.

Journal

  • Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE))

    Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)) 72(4), I_975-I_983, 2016

    Japan Society of Civil Engineers

Codes

Page Top