Lithospheric flexure and rheology determined by climate cycle markers in the Corinth Rift

Area of Science:

• Geophysics
• Tectonics
• Geomorphology

Background:

• Continental rift systems are crucial for understanding tectonic plate movement and seismic hazards.
• Geomorphic strain markers provide insights into the long-term mechanical behavior of rift systems.
• The Corinth Rift offers a unique geological record influenced by Pleistocene climate cycles.

Purpose of the Study:

• To analyze the 3D geometry of Pleistocene marine terraces and flexural rift-flank uplift in the Corinth Rift.
• To integrate onshore and offshore data for a comprehensive view of rift flexural deformation.
• To constrain the mechanical behavior and seismic hazards of continental rift systems.

Main Methods:

• High-resolution topographic analysis of emerged marine terraces.
• Integration of onshore geomorphic data with offshore seismic data.
• Lithospheric scale finite element modeling (3 and 5-layered).

Main Results:

• Derived an average slip rate of 4.5-9.0 mm/yr on the master fault over the past ~610 ka.
• Determined an uplift/subsidence ratio of 1:1.1-2.4.
• Reproduced flexure patterns using finite element models, indicating coseismic slip and postseismic viscous relaxation.

Conclusions:

• Flexural deformation in the Corinth Rift is attributed to coseismic slip on normal faults and subsequent viscous relaxation.
• This mechanism likely characterizes rapid, localized extension in continental lithosphere.
• Findings enhance understanding of rift mechanics and associated seismic risks.