Tackling the weathering with low ranks: Handling the complex near surface of land seismic data with low-rank-based methods

Imaging and inversion with seismic data recorded with sources and receivers at the surface are powerful tools to infer knowledge about the subsurface. However, creating an image with seismic data is unfortunately not as easy as taking a picture with a smartphone. The estimated subsurface models in many situations are far from ideal due to the...

Seismic-interferometric applications for near-surface and mineral exploration

Seismic methods are widely used for the exploration of the Earth’s subsurface. While they allow higher resolution compared to other geophysical methods, their performance depends on site and geological characteristics, and the volume and type of recorded information. Additionally, data processing plays a critical role in the efficacy of the...

Surface-waves suppression using seismic interferometry for imaging and monitoring of the Groningen subsurface

High-resolution seismic reflections are essential for imaging and monitoring applications using data-driven methods such as seismic interferometry (SI) and Marchenko redatuming. For seismic land surveys using sources and receivers at the surface, the surface waves are the dominant noises that mask the reflections. We use SI to suppress surface...

Surface-related multiple estimation and removal with focus on shallow water

For exploration and development of the earth, seismic surveys are acquired to provide information about the subsurface, within specifications of accuracy set by geologists and engineers, and within business constraints on budgets and turn-around time for processing and interpretation of the data. The case of seismic surveys that are acquired,...

Nonlinear beamforming seismic data reconstruction: A novel kinematic wavefront based method

In 3D seismic data acquisition, sufficiently dense spatial sampling is most often not possible, because of physical, financial, and temporal constraints. The resulting aliased data is a major obstacle for accurate subsurface images. Therefore, methods are needed to reconstruct these sparse data to an adequate sampling. We develop a novel...

Methods for reducing error in approximations of the Rayleigh integral

The goal of seismic imaging is to create a model of the subsurface from samples of a transmitted wavefield that is reflected in soil layers.<br/>The created model can be used to locate storage possibilities for CO2 or H2 or to find oil and gas reservoirs or other natural resources.<br/>Seismic imaging relies on the propagation of wavefields,...

Impact of Focal Depth on Short-Term Earthquake Prediction using Deep Learning

Due to the devastating consequences of earthquakes, predicting their occurrence before the first strike has been a long standing research topic. Deep learning models have been used to facilitate prediction, using seismograph data to attempt to classify an earthquake right before it happens. However, this is a difficult task and research needs to...

Earthquake Prediction: A MLP & SVM Comparison

Multi-Layer Perceptron and Support Vector Machine have both been widely used in machine learning. In this research paper, these models have been applied to binary classification on an individual time series basis. The goal was to see whether they can predict earthquakes, using earthquakes measured at specific stations across New Zealand. As it...

How does a CNN mixed with LSTM methods compare with the individual one in predicting earthquakes?

Earthquakes are one of the most dangerous natural disasters that occur worldwide. Predicting them is one of the unsolved problems in the field of science. In the past decade, there has been an increase in seismic monitoring stations worldwide, which has allowed us to design and implement data-driven and deep learning solutions. In this paper, we...

An Integrated Multiscale Method for the Characterisation of Active Faults in Offshore Areas. The Case of Sant’Eufemia Gulf (Offshore Calabria, Italy)

Diagnostic morphological features (e.g., rectilinear seafloor scarps) and lateral offsets of the Upper Quaternary deposits are used to infer active faults in offshore areas. Although they deform a significant seafloor region, the active faults are not necessarily capable of producing large earthquakes as they correspond to shallow structures...

Seismological characterization of the Theistareykir geothermal field (Iceland)

In 2017 the National Power Company in Iceland, Landsvirkjun, started the operation of a geother- mal power plant in Theistareykir (Northeastern Iceland). The plant’s operation requires extraction, circulation, and injection of the geothermal fluids to produce energy. These processes depend on the existing fracture network of the reservoir....

Fast and robust low-rank approximation for five-dimensional seismic data reconstruction

Five-dimensional (5D) seismic data reconstruction becomes more appealing in recent years because it takes advantage of five physical dimensions of the seismic data and can reconstruct data with large gap. The low-rank approximation approach is one of the most effective methods for reconstructing 5D dataset. However, the main disadvantage of...

The value of 4D seismic data to production forecasting

Minimizing the mismatch in the output of a petroleum reservoir model to 4D seismic data has the potential to increase its production forecast accuracy. However, the impact of 4D seismic data on the economic value of improved reservoir management decisions enforced during the production forecast has not been quantified. This work investigates the...

Inversion methods for the separation of blended data

The recording and storage capacity of modern seismic acquisition systems is continuously growing, enabling denser sampling and the acquisition of better-quality data. One big hurdle is survey time, since the duration of a survey is directly proportional to the number of sources fired. The proposed way forward is to deploy nearly simultaneous...

The Reconstruction of Missing Marine Seismic Data

To evaluate the subsurface, seismic surveys are carried out. A requirement for the processing of these data is that it is dense and regularly sampled and it should also include the near-offsets. Because these data cannot be acquired in practice for towed marine surveys, it should be obtained by inter- and extrapolation. The first objective of...

Data assimilation in reservoir management

The research presented in this thesis aims at improving computer models that allow simulations of water, oil and gas flows in subsurface petroleum reservoirs. This is done by integrating, or assimilating, measurements into physics-bases models. In recent years petroleum technology has developed rapidly. Nowadays wells can be drilled to a depth...

Reflector Imaging