Browsing Institutt for elektroniske systemer by Journals "Geophysics"
Now showing items 1-7 of 7
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An adapted eigenvalue-based filter for ocean ambient noise processing
(Peer reviewed; Journal article, 2020)Accurate approximations of Green’s functions retrieved from the correlations of ambient noise require a homogeneous distribution of random and uncorrelated noise sources. In the real world, the existence of highly coherent, ... -
Comparing the broadband acoustic frequency response of single, clustered and arrays of marine air guns
(Peer reviewed; Journal article, 2020)Field data acquired from a seismic vessel by a seabed hydrophone is used to analyze the broadband response (10 Hz to 62.5 kHz) for various source configurations: single air guns, clustered air guns, and a full array ... -
Estimating source signatures from source-over-spread marine seismic data
(Journal article; Peer reviewed, 2018)Recent developments in marine seismic acquisition include deploying a source vessel above a towed-streamer spread. We have developed an inversion algorithm to estimate source signatures for such acquisition configurations, ... -
Numerical study of the effect of cement defects on flexural-wave logging
(Journal article; Peer reviewed, 2019)Cement-bond evaluation is needed for new wells and plug and abandonment activities. The ultrasonic leaky Lamb-wave (also called the flexural-wave) technique, in combination with the pulse-echo technique, has been widely ... -
On low frequencies emitted by air guns at very shallow depths - An experimental study
(Journal article; Peer reviewed, 2019)In marine seismic acquisition, the enhancement of frequency amplitudes below 5 Hz is of special interest because it improves imaging of the subsurface. The frequency content of the air gun, the most commonly used marine ... -
Repeatability of high-resolution 3D seismic data
(Journal article; Peer reviewed, 2018)High-resolution 4D (HR4D) seismic data have the potential for improving the current state-of-the-art in detecting shallow (≤ 500 − 1000 m below seafloor) subsurface changes on a very fine scale (approximately 3–6 m). ... -
Tube-wave monitoring as a method to detect shear modulus changes around boreholes: A case study
(Peer reviewed; Journal article, 2021)Monitoring the shear modulus of formations around boreholes is of interest for various applications, ranging from near-surface investigation to reservoir monitoring. Downhole logging tools and borehole seismic are common ...