This study investigates the spectral distribution of the wave energy in a coral reef-lagoon system, focusing on very low frequency waves (VLF) and among them resonant waves. The data analysis is constructed on a dedicated methodology for identifying evanescent resonant waves, mainly based on the elaboration of two criteria: the energy persistence and the phase shift. The methodology is used on field data from an in-situ campaign in Maupiti Island (French Polynesia). Wave energy spectra are calculated at various positions from pressure time series; the method developed then results in persistence spectrograms that demonstrate how VLF (and possibly resonant waves) evolve in time and space in the Maupiti lagoon and across the Maupiti barrier.
