Blar i Publikasjoner fra CRIStin - NTNU på tidsskrift "Geophysics"
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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 ... -
A one-step Bayesian inversion framework for 3D reservoir characterization based on a Gaussian mixture model-A Norwegian Sea demonstration
(Peer reviewed; Journal article, 2021)We have developed a one-step approach for Bayesian prediction and uncertainty quantification of lithology/fluid classes, petrophysical properties, and elastic attributes conditional on prestack 3D seismic amplitude-varia ... -
Quick clay monitoring using distributed acoustic sensing: A case study from Rissa, Norway
(Peer reviewed; Journal article, 2023)Quick clay avalanche is one of the most devastating landslide types worldwide. Hence, an early warning system is in demand to mitigate the fatal consequences caused by such events. To address this, distributed acoustic ... -
Reducing high-frequency ghost cavitation signals from marine air-gun arrays
(Journal article; Peer reviewed, 2016)Ghost cavitation, which is a term describing that cavitation bubbles are generated acoustically, has been hypothesized to occur when the ghost reflected signals from many individual air guns beneath the sea surface produce ... -
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). ... -
Seismic attribute benchmarking on instantaneous frequency
(Journal article; Peer reviewed, 2019)The complex seismic trace analysis is a widely applied and versatile method for computing seismic attributes. Instantaneous frequency is an important complex trace attribute, and it is generally used for identifying specific ... -
Statistical modeling for real time pore pressure prediction from pre-drill analysis and well logs
(Journal article; Peer reviewed, 2019)The challenge of pore pressure prediction in an overpressured area near a well is studied. Predrill understanding of pore pressure is available from a 3D geologic model for pressure buildup and release using a basin modeling ... -
Streamer depth versus vessel and seismic interference noise
(Journal article; Peer reviewed, 2017) -
Stress Path Dependent Velocities in Shales: Impact on 4D Seismic Interpretation
(Journal article; Peer reviewed, 2018)Overburden stresses and pore pressure are altered by depletion or inflation of a subsurface reservoir, leading to seismic travel time and reflectivity changes that may be interpreted as footprints of reservoir drainage or ... -
The impact of saturation on seismic dispersion in shales — Laboratory measurements
(Journal article; Peer reviewed, 2018)Previous studies found a significant increase of acoustic velocities between seismic and ultrasonic frequencies (seismic dispersion) for shales, which would have to be taken into account when comparing seismic or sonic ... -
Three-dimensional magnetotelluric modelling in a mixed space-wavenumber domain
(Peer reviewed; Journal article, 2022)We have developed a new 3D magnetotelluric modeling scheme in a mixed space-wavenumber domain. The modeling scheme is based on using a 2D Fourier transform along two horizontal directions to solve a vector-scalar potential ... -
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 ... -
Variable source depth acquisition for improved marine broadband seismic data
(Journal article; Peer reviewed, 2015-05)In marine seismic data acquisition, varying the source depth along a sail line gives diversity in sequential shot gather frequency spectra. Undesired alterations of the frequency spectra are created by the source ghost and ... -
Velocity-attenuation model from check-shot drift trends in North Sea well data
(Peer reviewed; Journal article, 2020)Seismic attenuation distorts phase and narrows bandwidth in seismic surveys. It is also an exploration attribute, as, for example, gas or overpressure, may create attenuation anomalies. Compensating attenuation in imaging ...