Two orthogonal pre-production seismic surveys and a seismic survey acquired after eight years of production from the Bullwinkle field (GC 65, Gulf of Mexico) reveal extraordinary seismic differences that are attributed to productioninduced changes in rock and fluid properties. Separate normalizations of these surveys demonstrate that timelapse results are improved by utilizing seismic surveys t...

To prove a direct relationship between the quasi-static electric field disturbances and seismic activity is a difficult, but actual task of the modern ionosphere physics. This paper presents new results on the processing and analysis of the quasi-static electric field in the upper ionosphere (h=800–900 km) observed from the satellite INTERCOSMOS-BULGARIA-1300 over earthquakes’ source regions (s...

 Large-scale subsurface fluid injection has the potential to trigger earthquakes. In addition to seismic hazard, reactivation of faults and fractures during CO2 injection has the potential to compromise storage integrity. These risks need to be taken into account when selecting potential carbon capture and storage (CCS) sites.  Deployment of seismometers at current large-scale CCS projects (m...

Finite difference is a simple, fast and effective numerical method for seismic wave modeling, and has been widely used in forward waveform inversion and reverse time migration. However, intensive calculation of three-dimensional seismic forward modeling has been restricting the industrial application of 3D pre-stack reverse time migration and inversion. Aiming at this problem, in this paper, a ...

In the fall of 1998, the Federal Highway Administration of the U.S. Department of Transportation initiated a series of studies related to the seismic performance of the U.S. national highway system. The research conducted under this study is intended to provide improved tools for evaluating and assessing the social costs and impacts of earthquakes on highway systems and bridges, and to reduce t...

The Hydraulic External Pre-Isolator (HEPI) is the first 6 degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO’s 5th science run, successfully cutting down the disturbance seen by LLO’s suspended optics in the two most prominent s...

[1] Using the example of the 1992 M 7.3 Landers earthquake, we show that in the aftermath of a large earthquake the depth extent of aftershocks shows an immediate deepening from pre-earthquake levels, followed by a time-dependent postseismic shallowing. We use these seismic data to constrain the change in the depth of the seismic-aseismic transition with time throughout the earthquake cycle. Mo...

To evaluate the seismic performance of pre-cast concrete shear wall with vertical reinforcements spliced by two different grout ways, quasi-static tests of two concrete shear walls holed by prefabricated corrugated pipe and one concrete shear wall holed by drawing out the pipe were tested. The test results showed that the wall holed by prefabricated corrugated pipe was basically the same as the...

self-centering pier (scp) has been viewed as a remarkable accomplishment which is able to sustain major lateral loading with reduced structure damage in seismic engineering. stiffness deterioration observed in experiment is vital for the seismic performance of self-centering concrete pier. in this contribution, the associated stiffness deterioration with respect to the structural damage is mode...