... a semi-infinite half-space without additional adjustments. To address this, certain boundary conditions which simulate the finite domain to behave like a semi-infinite half space are used. These conditions are enforced on the essential boundaries, which otherwise reflect the transient wave propagation...

... Full waveform inversion (FWI) using reflections can provide velocity update for deeper target compared to conventional FWI using refractions and diving waves. For reflection FWI (RFWI), demigration is a key step to create synthetic reflection data. In this paper, we will focus on analyzing...

... We propose a new diffraction-separation method that uses a geometry mode decomposition (GMD) algorithm to remove reflections and separate diffractions in the common-offset or poststack domain. The key idea of this method is based on the fact that, in the frequency– wavenumber ( f – k ) domain...

... Diffractions are the seismic response of subsurface geological discontinuities, and thus, carry detailed geological information in 3D seismic exploration. It is a challenge to separate weak diffractions from specular reflections, especially when they have similar kinematical characteristics...

... Land seismic challenges are usually attributed to superimposed near-surface noise. We suggest that small- scale near-surface scattering distorts the reflections themselves via a mechanism we refer to as “seismic speckle,” similar to speckle noise in optics and acoustics. We describe a simple...

.... production logging reservoir characterization cable production control upstream oil & gas production monitoring international reflection applied geoscience bakulin exploration geophysicist surface seismic trench silvestrov geophone reservoir surveillance das cable saudi aramco sensor...

... The separation of the reflected and diffracted wavefields has been a crucial challenge in both seismic and ground-penetrating radar (GPR) data processing for many years. Different deterministic methods based on wavefront attributes, adaptive subtraction of reflections or plane-wave destruction...

... characterization and evaluation. According to the theories of geomorphology, media can be divided into two major parts, namely the long and short cycles, and the corresponding seismic signals are regarded as the combination of the reflections from these two parts. The long cycles correspond to the macro lithologic...

... to distinguish internal multiples from primary reflections when the subsurface is complex. An extended single-sided autofocusing guided by inverse-scattering theory is introduced to remove internal multiples in a data-driven manner. In this study, we explore the potential of neural networks in identifying...

... and post-stack data, demonstrating that CS ideas could be successfully applied to recover missing data. reconstruction exploration geophysicist applied geoscience reservoir characterization international herrmann upstream oil & gas operator american association reflection energy 10...

... instabilities to ultimate fracture prediction, like data processing and NDE calculation. On this basis, a new workflow is established on a wavefield separation that aims to elevate waveform quality by suppressing undesired noises and reflections. Then NDE calculation is reformulated as an inversion problem...

..., velocity analyses and tomography are not available for shallow converted P- to S-wave (PS-wave) data because of sparse node acquisition and low S-wave velocities. Conventional techniques use reflections from just below the seabed to invert for the elastic properties V P , V S and density ρ . We...

... scenario international seismic model reservoir characterization exploration geophysicist applied geoscience reflection brazilian geophysical society fd modeling impedance workflow american association geophysics equation Building high-resolution models and synthetic seismic data to evaluate...

... with specific objectives and tailored inputs. Between FWI loops, conventional reflection tomography and interpretation for special lithologies provided a more accurate input model for FWI convergence. The field data example with the proposed workflow greatly improved the model kinematics by capturing rapid...

... to determine AVA. This approach naturally corrects for a multitude of other amplitude effects including reflector geometry and transmission losses, and it deals correctly with near-critical and post-critical reflections. FWI-based work-flows are consequently simpler than conventional work-flows, and AVA...

... For some complex structures with thin interbedded coal or fault, the coal contained in sand reservoirs seriously hinders reservoir description and fluid identification of subsurface formations. The strong shielding effect of coal on sand reflection can easily lead to false bright spots...

... vibroseis exploration geophysicist international reservoir characterization simulation american association geo-exploration science upstream oil & gas application jilin university reflection exploration equation applied geoscience technology energy 10 gong geophysics wedge...

... In exploration seismology, the reflections have been extensively used for imaging and inversion to detect hydrocarbon and mine resources, which are generated from subsurface continuous impedance interfaces. When the reflectors are not continuous and their size reduces to less than a half...

... as converted and reflected signals. In addition to traditional approaches for microseismic event location and source mechanism analysis, DAS recordings can be used to image induced fractures using reflections. The reflections may be generated by hydraulic fractures from earlier treatment stages. We use...

... which can use all data residual (including the reflection residual). We demonstrate the successful application of IEI on a 2D marine seismic data example. We show we can estimate a reliable velocity model with IEI and a high-resolution velocity model with IEI+FWI using 24 Hz data. upstream oil...