Detection and mapping of Earth body resonances with continuous GPS

Abstract

I recently reported temporal proof that M_w5.6+ strong earthquakes occur due to (as the lithosphere rides on) vast waves of the tidally driven and gravitationally aided 1–72h long-periodic Earth body resonance (EBR). Here I report a methodologically independent spatial proof of EBR, conclusively showing that tremors are not the only earthquake type caused by mechanical resonance: observations of actual EBR waves in solid matter using continuous Global Positioning System (cGPS) and of their triggering M_w5.6+ earthquakes. Superharmonic resonance periods from the EBR’s 55’–15 days (0.303 mHz–0.7716 μHz) band are thus recoverable in spectra of International Terrestrial Reference Frame (ITRF2014) positional components solved kinematically from 30-s cGPS samplings. The signal is so pure, strong, and stable that even daylong components are constantly periodic at or above 99%-significance, with very high statistical fidelity, ϕ≫12, and ϕ≪12 characterizing overtones or undertones. cGPS stations have diurnal EBR fingerprints: unique sets of ~13–18 EBR frequencies, most clearly formed during ~M_w6+ quiescence, enabling depiction of EBR orientation for real-time EBR mapping. Furthermore, weeklong component time series reveal complete EBR and expected undertones as the signature of EBR’s companion sympathetic resonances, with very high ϕ≫12. Also, I demonstrate EBR mapping using the Mexico City–Los Angeles–San Francisco cGPS profile alongside a tectonic plate boundary, successfully depicting the preparation phase of the 2020 Puerto Rico M_w6.4–M_w6.6 earthquakes sequence. I finish by showing that the EBR triggered the 2019 Ridgecrest M_w6.4–M_w7.1 earthquakes sequence. EBR maps can now be produced for seismic prediction/forecasting and unobscuring (decoupling EBR frequencies) from geophysical observables like stress and strain. EBR engulfs the Earth’s crust, forming the resonance wind whose role and incessantness demote mantle convection from the working hypothesis of geophysics and whose applications include geophysical prospecting and detection at all scales and times. A previously unaccounted-for fundamental force of geophysics, the impulsive EBR spans the vastest energy bands, invalidating any previous claims of seismic detections of gravitational wave signals from deep space, such as by the LIGO experiment.

        ARK: https://n2t.net/ark:/88439/x073994

Permalink: https://geophysicsjournal.com/article/313

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