The analysis and interpretation of microseismicity induced by a collapsing solution mining cavity: A contribution for progress in hazard assessment of underground cavities

Abstract : In order to improve our understanding of hazardous underground cavities and its microseismic response, the development and collapse of a ~ 200 m wide salt solution mining cavity was monitored at Cerville-Buissoncourt in the Lorraine basin in NE France. The majority of the obtained dataset (~80%) was constituted of numerous unusual microseismic swarming events (~50.000 event files). This thesis presents innovative methods able to treat this specific microseismic data set, whose results provide new and fundamental insights into the principal characteristics of caving and collapsing related microseismicity and hazard assessment of excavated underground formations. The principal results are as follows: (i) the individual microseismic events are comparable to small natural tectonic earthquakes with moment magnitudes Mw ranging from around -3 to 1. (ii) Source mechanisms for most microseismic events are remarkable stable and demonstrate a predominant thrust faulting (double-couple) regime with faults similarly oriented NW-SE, dipping 35°-55° , what might be related to the presence of systematically arranged pre-existing fractures. (iii) The origin of microseismic swarming is suggested in the incapacity to sustain larger strains and to release larger stresses, what seems to be related to the mechanical constitution of the rock strata overlying the cavity (i.e. low strength materials). (iv) Caving and collapsing periods at the cavity roof are associated with systematic, self- reinforcing dynamics and have a distinct microseismic response, clearly observable from statistical analysis, which can be precisely described by empirical laws. The performed analysis and interpretation of the microseismicity at Cerville-Buissoncourt has shown that microseismic monitoring is a useful tool to constrain the mechanical and dynamical characteristics of an evolving and collapsing hazardous underground cavity
Complete list of metadatas

Cited literature [256 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01751432
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 1:19:16 PM
Last modification on : Friday, April 5, 2019 - 8:21:42 PM

File

DDOC_T_2015_0022_KINSCHER.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01751432, version 1

Citation

Jannes Lennart Kinscher. The analysis and interpretation of microseismicity induced by a collapsing solution mining cavity: A contribution for progress in hazard assessment of underground cavities. Earth Sciences. Université de Lorraine, 2015. English. ⟨NNT : 2015LORR0022⟩. ⟨tel-01751432⟩

Share

Metrics

Record views

64

Files downloads

19