Tsoft: graphical and interactive software for the analysis of time series and Earth tides

We present Tsoft, a graphical interactive analysis software package originally dedicated to the analysis and processing of gravity time series. Tsoft can also be used to process and analyze all sorts of time series like seismic or other environmental signals. The Tsoft approach has a number of important advantages in the area of pre-treatment of the data (correction of artefacts such as spikes and steps), because the user can always inspect what happened and intervene manually. The graphical environment is also very convenient for the detection, isolation and analysis of events (e.g. earthquakes). Lastly, errors in the analysis path are easily detected, because the software shows a graphical representation of the results at each stage of the analysis. In this article we describe first the general data structure and the possible data manipulations and computations. Then, we present the correcting tools dealing with unwanted steps, spikes and gaps in raw data. Afterwards, we describe the module dedicated to the computation of tidal signals. Lastly, we give an overview of the most used computing tools like spectral analysis and multilinear least-squares fit.

[1]  M. Camp.  Measuring seismic normal modes with the GWR C021 superconducting gravimeter , 1999 .

[2]  Terry Quinn,et al.  Sixth International Comparison of Absolute Gravimeters (ICAG-2001) , 2002 .

[3]  C. Chatfield,et al.  Fourier Analysis of Time Series: An Introduction , 1977, IEEE Transactions on Systems, Man, and Cybernetics.

[4]  Matthias Becker,et al.  Adjustment of Gravity Measurement at the Sixth International Comparison of Absolute Gravimeters ICAG-2001 , 2002 .

[5]  Y. Tamura.  A harmonic development of the tide-generating potential , 1987 .

[6]  O. Francis,et al.  Accurate transfer function determination for superconducting gravimeters , 2000 .

[7]  H.-G. Wenzel,et al.  The nanogal software : Earth tide data processing package ETERNA 3.30 , 1996 .

[8]  J. Arnoso,et al.  Program VAV/2000 for Tidal Analysis of Unevenly Spaced Data with Irregular Drift and Colored Noise , 2001 .

[9]  R. Warnant,et al.  Indication of the uplift of the Ardenne in long‐term gravity variations in Membach (Belgium) , 2004 .

[10]  F. Roosbeek.  RATGP95: a harmonic development of the tide-generating potential using an analytical method. , 1996 .

[11]  T. Baker,et al.  Validating Earth and ocean tide models using tidal gravity measurements , 2003 .

[12]  J. Wahr,et al.  Tides for a convective Earth , 1999 .

[13]  John M. Wahr,et al.  Body tides on an elliptical, rotating, elastic and oceanless earth , 1981 .

[14]  O. Kulhánek.  Introduction to Digital Filtering in Geophysics , 1976 .

[15]  O. Francis.  Calibration of the C021 Superconducting Gravimeter in Membach (Belgium) Using 47 Days of Absolute Gravity Measurements , 1997 .

[16]  O. Francis,et al.  Two years of continuous measurements of tidal and nontidal variations of gravity in Boulder, Colorado , 1998 .