A passive seismic monitoring campaign was carried out in the frame of a CO2-Enhanced Oil Recovery (EOR) pilot project in Alberta, Canada. Our analysis focuses on a two-week period during which prominent downhole pressure fluctuations in the reservoir were accompanied by a leakage of CO2 and CH4 along the monitoring well equipped with an array of short-period borehole geophones. We applied state...

Abstract. A series of transient seismic events were discovered in passive recordings from 2-D geophone arrays deployed at a frost polygon site Adventdalen, Svalbard. These contain high proportion surface wave energy and produce high-quality dispersion images using an apparent offset re-sorting inter-trace delay minimisation technique to locate the source, followed by cross-correlation beamformi...

By taking advantage of the information carried by entire seismic wavefield, Full Waveform Inversion (FWI) is able to yield higher resolution subsurface velocity models than traveltime tomography. However, FWI heavily relies on knowledge source and good initial models, could be easily trapped into local minima caused cycle skipping issue because its high nonlinearity. To mitigate these issues in...

Now that the world has well and truly crossed the threshold to the 21st century, it seems timely to review the progress of lithospheric seismic imaging and comment on recent developments in the field. In the context of this special issue, lithospheric seismic imaging refers to any kind of seismic study that gives rise to multidimensional (2-D or 3-D) views of the Earth's interior, from the shal...

In the last two decades, there has been an increasing interest in structural engineering control methods. Shape memory alloys and seismic isolation systems are examples of passive control systems that use of any one alone, effectively improve the seismic performance of the structure. Characteristics such as large strain range without any residual deformation, high damping capacity, excellent re...

Français. La méthode d’imagerie passive en sismologie a été développée récemment en vue d’imager la croûte terrestre à partir d’enregistrements du bruit sismique. Elle repose sur le calcul des fonctions de corrélation de ce bruit. Nous donnons dans cet article des formules explicites pour cette corrélation dans le régime “semi-classique”. Pour cela, nous définissons le spectre de puissance d’un...

An innovative lateral force resisting system is investigated that allows steel braced frames to uplift and rock on their foundation, partially isolating the frame. Passive energy dissipation devices are implemented at the uplifting location to control the rocking response to within allowable limits. The structure’s gravitational forces provide an inherent restoring force during the rocking resp...