Deformation patterns associated with the seismic cycle of the 27 February Maule earthquake segment at various spatiotemporal scales

• Applicant: Professor Manfred Strecker, Ph.D.
• Subject Area: Geophysics
• Term: from 2011 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 197097170

The overarching aims of the group proposal have been described in the summary document. Strain accumulation and release during the subduction-earthquake cycle governs the recurrence and magnitude of destructive earthquakes and associated tsunamis, such as the 2010 Maule event. Understanding the relation between long-term deformation patterns of forearcs manifested in the geology and geomorphology, and co-seismic megathrust slip is of utmost importance for deciphering the mechanisms governing the earthquake process and assessments of seismic hazards. In this study we will obtain detailed records of: (1) strain accumulation; (2) strain release; and (3) long-term (103- 105 yr) forearc deformation that integrates over several earthquake cycles, along strike of the Maule rupture. With this quantitative information, we will tackle fundamental problems of ongoing research, including the spatiotemporal sustenance of seismic asperities; potential earthquake precursory signals at decadal scale; and the use of coastal deformation gradients to predict megathrust slip. Our approach entails obtaining: (1) time series of land-level changes during the full inter-seismic period before the Maule event as a proxy for strain accumulation (geodetic, geomorphic and historical data); (2) a complete paleoseismic record at centennial to millennial time scales through a sedimentologic and geochronologic analysis of turbidites as proxy for strain release; and (3) coastal uplift rates deduced from deformed marine terraces and morphometric indices of drainage basins as proxy for permanent strain accumulated over several earthquake cycles.

• DFG Programme: Research Grants
• Participating Person: Professor Dr. Frank Krüger