Reducing near-surface artifacts from the crossline direction by full-waveform inversion of interferometric surface waves

Seismic incoherent noise and waves scattered from objects in the crossline directions can cause 2D elastic full-waveform inversion (FWI) to produce artifacts in the resulting 2D models. We develop a complete workflow that can determine subsurface S-wave velocity (VS) models inverted from 2D near-surface seismic data more stably. We make use...

Seismic imaging using an e-vib: A case study analyzing the signal properties of a seismic vibrator driven by electric linear synchronous motors (LSM's)

Seismic imaging characteristics of a prototype electrically driven, linear synchronous motor-based, vertical-force seismic vibrator ("e-vib") were evaluated at a site in the Netherlands. The system weighs 1.65 t and excites seismic signals with a peak force of 6.7 kN. Data were recorded along two collocated geophone-based nodal and...

Single-Material Graphene Thermocouples

On-chip temperature sensing on a micro- to nanometer scale is becoming more desirable as the complexity of nanodevices keeps increasing and their downscaling continues. The continuation of this trend makes thermal probing and management more and more challenging. This highlights the need for scalable and reliable temperature sensors, which...

Marchenko Focusing Without Up/Down Decomposition

Current Marchenko algorithms require up/down separation, and solving the Marchenko equation enables one to retrieve the up/down components of the Green's function. We propose an iterative scheme to relax the need for up/down separation for focusing. By presenting a visual tour, we show how to retrieve the Green's function in the subsurface at...

A field data example of Marchenko multiple elimination

Multiple reflections are often considered as noise in seismic data. Dealing with them has attracted much attention from industry and academia. A variety of schemes have been developed for removal of free-surface multiple reflections and success has been achieved in numerical and field datasets. However, less attention has been directed toward...

A Survey on the Adoption of GIS Data and Standards in Urban Application Domains

GIS has become an important part of many disciplines and supports a vast range of applications. It is used everywhere, from agriculture to public health care. Furthermore, with the advances in technologies, the availability of GIS data and software support has grown exponentially. In this paper, we present the results of our international survey...

The Singular Optics of Random Light: a 2D vectorial investigation

In this thesis, we explore the physics of optical singularities. We investigate them in light waves propagating randomly in a planar nanophotonic chip. With a custom-built nearfield microscope, we map the electromagnetic field resulting from the interference of these light waves. Our technique gives access to the full vectorial and complex...

Marchenko redatuming by adaptive double-focusing on 2D and 3D field data of the Santos basin

The Santos basin in Brazil suffers from strong internal multiples that overlap with primaries from the pre-salt reservoirs. We propose an adaptive double-focusing method for the removal of these multiples to obtain a correct image of the target area. The proposed method applies a form of source-receiver Marchenko redatuming to the reflection...

2D InP photonic crystal fabrication process development

We have developed a reliable process to fabricate high quality 2D air-hole and dielectric column InP photonic crystals with a high aspect ratio on a STS production tool using ICP N2+Cl2 plasma. The photonic crystals have a triangular lattice with lattice constant of 400 nm and air-hole and dielectric column radius of 120 nm. Large efforts have...