Year: 2023 First Published: EAGE Authors: Mahesh Kalita, Chris Purcell, and Lorenzo Casasanta Summary Full-waveform inversion finds a subsurface model that minimizes the misfit between modelled seismic data and observations. It’s well known that the L2-norm of the waveforms difference is prone to cycle-skipping due to the presence of local minima. We introduce the soft-dynamic […]

Year: 2023 First Published: IMAGE Authors: Mahesh Kalita*, and Lorenzo Casasanta Summary Full-waveform inversion (FWI) aims to obtain accurate subsurface models by minimizing the discrepancy between observed seismic data and modeled data. However, the commonly used L2-norm waveform difference misfit functional is prone to cycle-skipping due to local minima. To address this issue, we propose […]

Year: 2023 First Published: IMAGE Authors: Mahesh Kalita, and Lorenzo Casasanta Summary We introduce soft-dynamic-time-warping-divergence and its sharp variant as misfit functionals in full- waveform inversion (FWI). These functionals maintain convexity for large model perturbations, making FWI less vulnerable to cycle-skipping. The sharp variant aims to remove the entropic regularization term from the warping process. […]

Year: 2023 First Published: IMAGE Authors: Arash JafarGandomi, Aparajita Nath, Sergio Grion Summary Marine seismic vibrators are considered serious contenders to air-gun arrays and are attractive as environmentally friendly sources. While the reduced environmental impact is highly attractive, an additional driver is the ability to control the characteristics of the released energy precisely. Here we […]

Year: 2023 First Published: IMAGE Authors: Jing Sun, Arash Jafargandomi, Julian Holden Summary In multicomponent ocean bottom seismic (OBS) acquisition, hydrophones and geophones (or accelerometers) are employed to record seismic signals. Combining records from the hydrophone (P-component) and the vertical geophone (Z-component) allows for elimination of the receiver-side ghost and water-layer multiples, when performing wavefield […]

Year: 2023 First Published: EAGE Vienna Workshop Authors: Hager, Rentsch Summary Air-gun sources and their environmental impact have been debated for a long time. While some of this debate might be exaggerated it is generally accepted that the high frequencies outside the seismic bandwidth are of no benefit to imaging or subsequent attribute inversions although […]

Year: 2023 First Published: IMAGE Authors: Rodrigo Felicio Fuck and Lorenzo Casasanta Summary We introduce a novel, computationally efficient model preconditioner, the guided filter, a multi-dimensional, structure-oriented, and edge-preserving filter, with a self- adjoint implementation which does not require a priori knowledge of the structural dip field. We show how to generalize the guided filter […]

Year: 2023 First Published: IMAGE Authors: Rodrigo Fuck and Lorenzo Casasanta Summary We introduce a novel computationally efficient model preconditioner, the guided filter, a multi-dimensional, structure-oriented, and edge-preserving filter, with a self-adjoint implementation which does not require apriori knowledge of the structural dip field. Model preconditioners are essential in geophysical ill-posed inverse problem to constrain […]

Shearwater GeoServices Strengthens Partnership with Agostinho Neto University in Angola, Providing Advanced Reveal Software Licenses and Seismic Data. Shearwater GeoServices is pleased to announce the continuation of its partnership with Agostinho Neto University in Angola. Together with local partner DDMS Ltd, Shearwater is supporting academic excellence by providing ten licenses to their state-of-the-art Reveal software, […]

In the immensity of the oceans, being away from family and friends can be tough. For years, our offshore colleagues have wrestled with the isolation that accompanies life on a vessel, struggling with a conventional internet connection, making them feel disconnected from the rest of the world. However, the evolution of technology has been a […]