eprintid: 1985
rev_number: 13
eprint_status: archive
userid: 10
dir: disk0/00/00/19/85
datestamp: 2017-09-19 09:51:46
lastmod: 2017-09-19 09:51:46
status_changed: 2017-09-19 09:51:46
type: conference_item
metadata_visibility: show
creators_name: Marcak, Henryk
creators_name: Lasak, Mateusz
creators_name: Mirek, Janusz
creators_id: marcak@agh.edu.pl
creators_id: mlasak@igf.edu.pl
creators_id: jmirek@agh.edu.pl
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland
corp_creators: Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland
title: Using the velocity of seismic waves estimated from ambient seismic noise
to assess the results of hydro-fracturing and the exploitation of shale-rock
formations
subjects: RP5
subjects: SHU
subjects: SS
divisions: SHEER-1
full_text_status: public
pres_type: speech
abstract: Wysin-2-H is a well drilled in the so-called shale gas region of Pomerania, northern Poland. A seismic network
was constructed around the well to study the seismic effects of activating of shale gas deposits by hydro-fracturing.
The network was also used for the measurements of seismic noise, although the net was not specifically designed
for this purpose.
The seismic noise directivity strongly influences the structure of correlograms. Therefore, this issue was re-
searched intensively. It is presented that arrival times of strong signals in the time intervals greater than 1 month
in frequency range 0,1 – 0,4 Hz are not disturbed by movement of source of seismic noise.
Due to presence of strong reflector in geological structure of Wysin region, the coda waves are reflected downward
and cannot be recorded by the network. It is shown that the only waves recorded in longer time lags, which have
signals visible on the correlograms, are horizontal waves recorded in one station. Using these waves, accuracy of
estimation of the relative velocity changes in geological strata is approximately 0,05 %.
Despite the depth of the shale gas deposits estimated for about 4000 m, it was assumed that correlograms
calculated for the seismic data before hydro-fracturing and correlograms for the data after activation of shale gas
deposits, with high gas production rate, should vary significantly and provide useful information about velocity
changes.
Due to complicated structure of shale gas deposits there was no meaningful gas output from the Wysin well.
Hence, the measurements of seismic noise have not indicate the changes of the velocity distribution before and
after hydro-fracturing.
date: 2017-04
date_type: published
event_title: EGU General Assembly 2017
event_location: Vienna, Austria
event_dates: 23–28 April 2017
event_type: conference
official_url: http://meetingorganizer.copernicus.org/EGU2017/EGU2017-3238.pdf
access_IS-EPOS: limited
owner: Publisher
citation:   Marcak, Henryk and Lasak, Mateusz and Mirek, Janusz  (2017) Using the velocity of seismic waves estimated from ambient seismic noise to assess the results of hydro-fracturing and the exploitation of shale-rock formations.  In: EGU General Assembly 2017, 23–28 April 2017, Vienna, Austria.     
document_url: https://episodesplatform.eu/eprints/1985/1/Marcak_et_al_2017_Using_the_velocity_of_seismic_waves_estimated_from_ambient_seismic_noise_Presentation.ppt