Controls of seismogenic zone width and subduction velocity on interplate seismicity: Insights from analog and numerical models

Fabio Corbi (1) , Robert Herrendörfer , Francesca Funiciello , Ylona van Dinther

1 Géosciences Montpellier

Correlations between geodynamic parameters and interplate seismicity characteristics in subduction zones are generally weak due to the short instrumental record and multiparameter influences. To investigate the role of subduction velocity V_s and the width of the seismogenic zone W on maximum magnitude M_max, seismic rate τ, characteristic recurrence rate τ_c, and moment release rate MRR, we use synthetic data sets from simplified analog and numerical models to gain insight into natural subduction zones seismicity. Our models suggest that M_max increases with W and is unaffected by V_s, τ increases with V_s, τ_c increases with V_s/W, and MRR increases with V_s × W. In nature, only the positive correlation between V_s and τ is significant. Random sampling of our time series suggest that the positive correlation between V_s and τ can be observed with short observation time windows. Other correlations, including M_max versus W, become clear only for time window lengths longer than 1/τ_c.

Mots clés: subduction megathrust earthquakes; analog modeling; numerical modeling; subduction velocity; seismogenic zone width

Domaines: Planète et Univers [physics]

Fabio Corbi, Robert Herrendörfer, Francesca Funiciello, Ylona van Dinther. Controls of seismogenic zone width and subduction velocity on interplate seismicity: Insights from analog and numerical models. Geophysical Research Letters, 2017, 44, pp.6082-6091. ⟨10.1002/2016GL072415⟩. ⟨insu-03661350⟩