Identification of a harmonic signal in the presence of additive noise, an unknown time base distortion, and an averaging effect

When environmental archives are sampled, its measured values are on a distance grid. However, in order to compare different data records, a time grid is needed. Distance-time relationships are non-linear, because the accretion rate of these archives depends on environmental factors. In environmental archives samples are taken over a volume in distance, rather than over a point in distance. This implies that the sample-values will be averaged over the volume of the sample. In this paper a method is proposed, which identifies the non-linearities in the time-distance relationship and corrects for the averaging effects. In order to assess the influence of the noise on the actual parameter values a Monte Carlo simulation was performed.