Intelligent Earth system sensing, scientific enquiry and discovery


Non-tidal tilt and strain signals observed at the Geodynamic Observatory Moxa, Thuringia

Thomas Jahr
Institute of Geosciences, Friedrich Schiller University Jena
Oral presentation

Since end of the 90s of the last century the at that time seismological station Moxa could be extended and developed to the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters (ASKANIA-Borehole-Tilt meter; ABT) in front of the observatory building and laser-strain meters in the gallery of the observatory. The steady renewal of the tilt- and strain meter ensemble has been continued during the last years: thus a new developed system could be installed in 2014. Because meanwhile the strain and tilt tidal parameters are well known for Moxa, a new installed measuring system can be calibrated successfully using the tidal signals and they can be compared with each other. Moreover, the question arises how non-tidal signals are displayed in the measured time series. The investigation of such signals which can be caused naturally or man-made, can result in different sensitivities for the various tilt- and strain meter systems, e.g. regarding barometric pressure loading and hydrological induced pore pressure effects. Comparison with modeling results is also a suitable option. Contemporaneously, a weather station exists for more than 15 years, and several measuring points of ground water and soil humidity changes as well as a snow cushion, so that at more than 17 points in the observatory and its surroundings environmental parameters are observed continuously and with high resolution. In this talk exemplarily some correlations between observed induced deformations and environmental parameters are described and discussed. Finally, the known physical relations allow to compile a plan for specific hydro-deformation experiments in order to improve the understanding of the particular hydrologic situation and the induced deformations at Moxa. New insights could lead to applications for in situ rock physics experiments and research.

Scientific Topic: 
Natural and anthropogenic subsurface fluid effects (Jacques Hinderer, Giuliana Rossi)
Presentation date time: 
Thursday, June 9, 2016 - 11:20 to 11:35