Gliding tremors associated with the 26 second microseism in the Gulf of Guinea

Abstract A location in the Gulf of Guinea, which emits monochromatic seismic waves at 26-second period, seemingly continuously, was identified 1960s. However, origin these remains enigmatic to date. Here we use three-component data from two arrays Africa, as well additional compiled around world, investigate tremors. We identify frequency glides accompanying previously known 26 s microseism start same and originate same, fixed Guinea. The stable characteristics tremors, their low range, implied large spatial scale, decades-long timescales where this phenomenon seems have been active, all point towards a gap our understanding long period oceanic volcanic signals. Since tremor is an important tool monitor volcanoes, may affect future forecasting activity.