Active Deformation Across the Western Anatolian Extensional Province (Türkiye) From Sentinel-1 InSAR.

Area of Science:

• Geodesy
• Tectonics
• Remote Sensing

Background:

• Quantifying interseismic deformation in fault networks with predominantly north-south motion is difficult due to limitations in Global Navigation Satellite System (GNSS) network density.
• Interferometric Synthetic Aperture Radar (InSAR) offers high spatial resolution but has low sensitivity to north-south motion, posing challenges for studying extensional regimes.

Purpose of the Study:

• To investigate the active normal fault network in Western Türkiye using InSAR, focusing on vertical deformation to overcome limitations in north-south motion detection.
• To analyze the high-resolution vertical velocity field to understand regional deformation patterns and deduce insights into fault activity in an extensional tectonic setting.

Main Methods:

• Utilizing InSAR data to analyze the vertical deformation component of the Western Anatolian Extensional Province.
• Systematically analyzing the high-resolution vertical velocity field to identify deformation patterns across individual faults and graben systems.
• Addressing challenges such as anthropogenic subsidence, urban uplift signals, topographic, and atmospheric disturbances in InSAR data.

Main Results:

• Tectonic deformation in large graben systems extends beyond main faults, with smaller faults also accommodating significant strain.
• Evidence supports a continuum model of deformation rather than discrete block models for the studied fault network.
• A potential correlation between recent seismicity and active interseismic surface deformation was observed.

Conclusions:

• InSAR time series analysis, despite challenges, provides valuable insights into interseismic deformation in extensional tectonic regimes.
• Observed deformation rates offer estimates of current activity for numerous faults in Western Türkiye.
• The findings highlight the importance of considering distributed deformation across fault networks, including smaller faults.