Coordinate differences between static and kinematic precise point positioning: a different approach in spectral analysis during the 2023 Kahramanmaraş earthquake

Karatay S., Erken F., PIRTI A., ARIKAN F.

Advances in Space Research, vol.77, no.4, pp.4663-4681, 2026 (SCI-Expanded, Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 77 Issue: 4
  • Publication Date: 2026
  • Doi Number: 10.1016/j.asr.2025.12.036
  • Journal Name: Advances in Space Research
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Compendex, INSPEC, MEDLINE
  • Page Numbers: pp.4663-4681
  • Keywords: Earthquake precursors, Geodetic seismology, GNSS monitoring, Pre-seismic detection, Precise point positioning, Spectral analysis, Static vs kinematic processing
  • Hacettepe University Affiliated: Yes

Abstract

This study investigates effects of static versus kinematic CSRS-PPP processing on coordinate differences ((Formula presented) ) during the 2023 Kahramanmaraş earthquake sequence in Türkiye. GNSS data from TNPGN-Active stations MAR1 and ANTE are analyzed across 10 pre-seismic days (January 28–February 6, 2023) using two approaches: daily spectral analysis with median filtering, detrending and FFT and combined analysis of concatenated time series. Results show processing modes produce discrepancies exceeding 35 % in dominant frequency characteristics and 68 % in spectral variance. We observe a counterintuitive distance paradox: ANTE station exhibits 87.5 % higher baseline frequency variability despite being 46 % farther from the epicenter than MAR1. Statistical analysis (p < 0.001) confirms these differences represent fundamental measurement uncertainties. The height component consistently shows highest processing sensitivity (variance ratios ≈ 2.67), while horizontal components show ratios of 2.2–2.7. During pre-seismic periods, MAR1 demonstrates frequency drift rates of 0.017 mHz/day and ANTE 0.025 mHz/day, suggesting coupling between preparatory earthquake processes and GNSS stability mechanisms. Spectral coherence analysis distinguishes geomagnetically quiet (0.75–0.85), disturbed (0.40–0.50) and pre-seismic (0.55–0.65) conditions, enabling separation of earthquake-related signals from atmospheric artifacts.