Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area
Volcanic rifting environments, such as in Iceland, are challenging for conventional seismic reflection methods using active surface seismic sources. This study demonstrates the potential of a novel technique, called Virtual Reflection Seismic Profiling (VRSP) for imaging reflections in geothermal re...
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Uppsala universitet, Geofysik
2020
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ftuppsalauniv:oai:DiVA.org:uu-413199 2023-05-15T16:51:58+02:00 Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area Stoch, Agnieszka 2020 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413199 eng eng Uppsala universitet, Geofysik Examensarbete vid Institutionen för geovetenskaper, 1650-6553 485 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413199 info:eu-repo/semantics/openAccess Hverahlíð geothermal area reflection seismic virtual reflection seismic profiling virtual shot gather cross-correlation autocorrelation Geophysics Geofysik Student thesis info:eu-repo/semantics/bachelorThesis text 2020 ftuppsalauniv 2023-02-23T21:52:54Z Volcanic rifting environments, such as in Iceland, are challenging for conventional seismic reflection methods using active surface seismic sources. This study demonstrates the potential of a novel technique, called Virtual Reflection Seismic Profiling (VRSP) for imaging reflections in geothermal regions, like Hverahlíð, where a dense seismic array recorded a number of local microearthquakes for cross-correlation. Uppsala University, in collaboration with Reykjavik Energy, recorded seismicity in Hverahlíð using both seismometers and geophones. Acquired data were processed using the VRSP method, which applies seismic interferometry only to selected events, in this thesis local microearthquakes. Cross-correlation of the signal from a microearthquake recorded at one of the stations, which acts as a virtual source, with a ghost reflection recorded by the remaining receivers, produces a virtual shot gather. Stacking each station’s result, for all available events, and following a conventional multichannel processing sequence resulted in two stacked seismic images. Potential reflections observed in the obtained sections could be associated with major feed zones identified in the area by the borehole measurements. Eight dynamite explosions were processed with a conventional seismic reflection method, as a complementary source to the microearthquakes. In the produced stacked seismic section two potential reflections could be observed. Results from both passive and active datasets were 3D visualised to verify whether the reflections correspond to each other between sections. Two horizons were traced throughout all three stacked sections. One more interface appeared on two images obtained from processing the passive data. This study shows promising results for using natural sources to image the subsurface in a challenging environment. Bachelor Thesis Iceland Uppsala University: Publications (DiVA) Hverahlíð ENVELOPE(-21.320,-21.320,64.009,64.009) |
institution |
Open Polar |
collection |
Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
Hverahlíð geothermal area reflection seismic virtual reflection seismic profiling virtual shot gather cross-correlation autocorrelation Geophysics Geofysik |
spellingShingle |
Hverahlíð geothermal area reflection seismic virtual reflection seismic profiling virtual shot gather cross-correlation autocorrelation Geophysics Geofysik Stoch, Agnieszka Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
topic_facet |
Hverahlíð geothermal area reflection seismic virtual reflection seismic profiling virtual shot gather cross-correlation autocorrelation Geophysics Geofysik |
description |
Volcanic rifting environments, such as in Iceland, are challenging for conventional seismic reflection methods using active surface seismic sources. This study demonstrates the potential of a novel technique, called Virtual Reflection Seismic Profiling (VRSP) for imaging reflections in geothermal regions, like Hverahlíð, where a dense seismic array recorded a number of local microearthquakes for cross-correlation. Uppsala University, in collaboration with Reykjavik Energy, recorded seismicity in Hverahlíð using both seismometers and geophones. Acquired data were processed using the VRSP method, which applies seismic interferometry only to selected events, in this thesis local microearthquakes. Cross-correlation of the signal from a microearthquake recorded at one of the stations, which acts as a virtual source, with a ghost reflection recorded by the remaining receivers, produces a virtual shot gather. Stacking each station’s result, for all available events, and following a conventional multichannel processing sequence resulted in two stacked seismic images. Potential reflections observed in the obtained sections could be associated with major feed zones identified in the area by the borehole measurements. Eight dynamite explosions were processed with a conventional seismic reflection method, as a complementary source to the microearthquakes. In the produced stacked seismic section two potential reflections could be observed. Results from both passive and active datasets were 3D visualised to verify whether the reflections correspond to each other between sections. Two horizons were traced throughout all three stacked sections. One more interface appeared on two images obtained from processing the passive data. This study shows promising results for using natural sources to image the subsurface in a challenging environment. |
format |
Bachelor Thesis |
author |
Stoch, Agnieszka |
author_facet |
Stoch, Agnieszka |
author_sort |
Stoch, Agnieszka |
title |
Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
title_short |
Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
title_full |
Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
title_fullStr |
Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
title_full_unstemmed |
Analysis of Seismic Data Acquired in the Hverahlíð Geothermal Area |
title_sort |
analysis of seismic data acquired in the hverahlíð geothermal area |
publisher |
Uppsala universitet, Geofysik |
publishDate |
2020 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413199 |
long_lat |
ENVELOPE(-21.320,-21.320,64.009,64.009) |
geographic |
Hverahlíð |
geographic_facet |
Hverahlíð |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
Examensarbete vid Institutionen för geovetenskaper, 1650-6553 485 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413199 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766042093999882240 |