Deep ocean waves hitting the shore should somehow induce this periodic microseism as a sliding of the tectonic plates with respect to each other. If there is a lattice like structure of incompressible cylindrical plates, the compression by sea waves arriving at shore induces a volume preserving vertical stretching of these cylinders inducing the detected Rayleigh wave.
Cyclotron periods of ions at MB are quantized and 26 s could be understood as a resonance period for the coupling between the tectonic dynamics and that of MB. The problem is that the periods associated with the deep ocean waves are below 20 s so that a linear coupling preserving frequency does not allow understanding of the 26 s period. However, non-linear coupling allows period doubling at the limit of chaos. Could 26 s period be seen as 8:th period doubling of
T=.1 s which corresponds to alpha rhythm in EEG and fundamental biorhythm, the secondary p-adic time scale of electron, and the cyclotron frequency of iron ion in the endogenous magnetic field Bend=(2/5)BE identified as monopole flux part of Earth's magnetic field BE and playing a key role in TGD inspired quantum biology?
For a summary of earlier postings see Latest progress in TGD.