Seismicity at an oil/gas field has been monitored with surface and borehole seismic networks. Sin... more Seismicity at an oil/gas field has been monitored with surface and borehole seismic networks. Since the seismic monitoring started in 1999, thousands of events have been recorded, located and analyzed. The ``surface'' seismic network consists of five stations with seismometers in shallow boreholes at 125-150 m depth. The deep network is made up of five downhole geophone arrays, each with
Five shallow borehole seismic stations were installed to monitor microearthquake activities in a ... more Five shallow borehole seismic stations were installed to monitor microearthquake activities in a carbonate oil field in northern Oman since 1999. This shallow network of seismic station operated continuously until 2002 after which intermittent seismic recording took place due to lack of maintenance and failure of some stations. The objectives of the study are to determine the microseismic parameters in
Microseismicity was monitored continuously for 2003 and 2004 years using shallow downhole seismic... more Microseismicity was monitored continuously for 2003 and 2004 years using shallow downhole seismic network in a carbonate oil field in Northern Oman. A total of 406 microearthquake events were analyzed to assess events location relative to producing horizons. The depth of the microearthquakes ranges from 0 to 2.95 km below the ground surface. The events location is confined to the
The discrete time wavelet transform has been used to develop software that detects seismic P and ... more The discrete time wavelet transform has been used to develop software that detects seismic P and S-phases. The detection algorithm is based on the enhanced amplitude and polarization information provided by the wavelet transform coefficients of the raw seismic data. The algorithm detects phases, determines arrival times and indicates the seismic event direction from three component seismic data that represents the ground displacement in three orthogonal directions. The essential concept is that strong features of the seismic signal are present in the wavelet coefficients across several scales of time and direction. The P-phase is detected by generating a function using polarization information while S-phase is detected by generating a function based on the transverse to radial amplitude ratio. These functions are shown to be very effective metrics in detecting P and S-phases and for determining their arrival times for low signal-to-noise arrivals. Results are compared with arrival times obtained by a human analyst as well as with a standard STA/LTA algorithm from local and regional earthquakes and found to be consistent.
Abstract This study presents the results of the first probabilistic seismic hazard assessment (PS... more Abstract This study presents the results of the first probabilistic seismic hazard assessment (PSHA) in the framework of logic tree for Oman. The earthquake catalogue was homogenized, declustered, and used to define seismotectonic source model that characterizes the seismicity of Oman. Two seismic source models were used in the current study; the first consists of 26 seismic source zones, while the second is expressing the alternative view that seismicity is uniform along the entire Makran and Zagros zones. The ...
Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2012
... is briefly described and the design procedure of the ISO 19901-2 seismic design guideline for... more ... is briefly described and the design procedure of the ISO 19901-2 seismic design guideline for offshore structures is highlighted. The following sections present probabilistic seismic hazard frameworks for the sliding displacement of offshore slopes (Rathje and Saygili 200825. ...
Seismicity at an oil/gas field has been monitored with surface and borehole seismic networks. Sin... more Seismicity at an oil/gas field has been monitored with surface and borehole seismic networks. Since the seismic monitoring started in 1999, thousands of events have been recorded, located and analyzed. The ``surface'' seismic network consists of five stations with seismometers in shallow boreholes at 125-150 m depth. The deep network is made up of five downhole geophone arrays, each with
Five shallow borehole seismic stations were installed to monitor microearthquake activities in a ... more Five shallow borehole seismic stations were installed to monitor microearthquake activities in a carbonate oil field in northern Oman since 1999. This shallow network of seismic station operated continuously until 2002 after which intermittent seismic recording took place due to lack of maintenance and failure of some stations. The objectives of the study are to determine the microseismic parameters in
Microseismicity was monitored continuously for 2003 and 2004 years using shallow downhole seismic... more Microseismicity was monitored continuously for 2003 and 2004 years using shallow downhole seismic network in a carbonate oil field in Northern Oman. A total of 406 microearthquake events were analyzed to assess events location relative to producing horizons. The depth of the microearthquakes ranges from 0 to 2.95 km below the ground surface. The events location is confined to the
The discrete time wavelet transform has been used to develop software that detects seismic P and ... more The discrete time wavelet transform has been used to develop software that detects seismic P and S-phases. The detection algorithm is based on the enhanced amplitude and polarization information provided by the wavelet transform coefficients of the raw seismic data. The algorithm detects phases, determines arrival times and indicates the seismic event direction from three component seismic data that represents the ground displacement in three orthogonal directions. The essential concept is that strong features of the seismic signal are present in the wavelet coefficients across several scales of time and direction. The P-phase is detected by generating a function using polarization information while S-phase is detected by generating a function based on the transverse to radial amplitude ratio. These functions are shown to be very effective metrics in detecting P and S-phases and for determining their arrival times for low signal-to-noise arrivals. Results are compared with arrival times obtained by a human analyst as well as with a standard STA/LTA algorithm from local and regional earthquakes and found to be consistent.
Abstract This study presents the results of the first probabilistic seismic hazard assessment (PS... more Abstract This study presents the results of the first probabilistic seismic hazard assessment (PSHA) in the framework of logic tree for Oman. The earthquake catalogue was homogenized, declustered, and used to define seismotectonic source model that characterizes the seismicity of Oman. Two seismic source models were used in the current study; the first consists of 26 seismic source zones, while the second is expressing the alternative view that seismicity is uniform along the entire Makran and Zagros zones. The ...
Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards, 2012
... is briefly described and the design procedure of the ISO 19901-2 seismic design guideline for... more ... is briefly described and the design procedure of the ISO 19901-2 seismic design guideline for offshore structures is highlighted. The following sections present probabilistic seismic hazard frameworks for the sliding displacement of offshore slopes (Rathje and Saygili 200825. ...
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