Statistical pre-processing and analyses of hydro-meteorological time series in a geologic clay site (methodology and first results for Mont Terri’s PP experiment)

This article presents a set of statistical methods for pre-processing (or pre-conditioning) and analyzing multivariate hydro-geologic time series, such as pore pressures and atmospheric pressure (temporal structures). The pre-processing methods are necessary to enhance or complete the signals due to defects in the observed time series (data gaps, spurious values, variable time steps). The statistical analyses aim, in fine, at characterizing the hydraulic behaviour of a clayey formation in the context of deep geologic disposal of radioactive waste. Pore water and atmospheric pressure time series from the Mont Terri rock laboratory (BPP-1 borehole) are taken as an example.