Changes in reservoir properties resulting from extracting hydrocarbons and injecting fluid are critical to optimize production. These properties can be characterized using waveform inversions of time-lapse seismic data. The conventional approach for analysis using waveform tomography is to take the difference of seismic inversion obtained using baseline and subsequent time-lapse datasets that a...

Shear-wave velocity ( ) is an important parameter used for site characterization in geotechnical engineering. However, dispersion curve inversion is challenging for most inversion methods due to its high non-linearity and mix-determined trait. In order to overcome these problems, in this study, a joint inversion strategy is proposed based on the particle swarm optimization (PSO) algorithm. The ...

Time-lapse seismic data are widely used for monitoring timevariant subsurface changes. Conventional analysis provides qualitative information by comparing results from consecutive surveys, whereas waveform inversion can retrieve quantitative estimates of reservoir properties through seismic waveform fitting. The quantitative evaluation of the physical parameters obtained by waveform inversion a...

Under operator, matrix and inverse theory, seismic-wave imaging can be considered a unified process—mapping from data space to model space. The main topics in seismic-wave imaging include (1) seismic-data interpolation, regularization and redatuming, which mainly decrease the imaging noise; (2) seismic-wave illumination analysis, which predicts whether a target reflector can be imaged and evalu...

S U M M A R Y We analyse radar interferometric and GPS observations of the displacement field from the 1995 July 30 Mw = 8.1 Antofagasta, Chile, earthquake and invert for the distribution of slip along the co-seismic fault plane. Using a fixed fault geometry, we compare the use of singular-value decomposition and constrained linear inversion to invert for the slip distribution and find that the...

Gas-hydrates are crystalline form of water and methane that form at high pressure and low temperature. They have attracted the global attention due to their wide-spread occurrences in the permafrost and outer continental margins; potential as major energy resources; role in climate change etc. It is estimated that the carbon in gas-hydrates is two times the carbon content in fossil fuel reserve...

With the development of computational power, there has been an increased focus on data-fitting related seismic inversion techniques for high fidelity seismic velocity model and image, such as full-waveform inversion and least square migration. However, though more advanced than conventional methods, these data fitting methods can be very expensive in terms of computational cost. Recently, vario...

We determine upper mantle seismic velocity heterogeneities below Southern California from the inversion of teleseismic travel-time residuals. Teleseismic P-wave arrival times are obtained from three temporary passive experiments and Southern California Seismic Network (SCSN) stations, producing good raypath coverage. The inversion is performed using a damped least-squares conjugate gradient met...

Seismic Inversion methods have been routinely used for estimating attributes like P-impedance, Simpedance, density, ratio of P-wave and S-wave velocity and elastic impedances from seismic and well log data. These attributes help to understand lithology and fluid contents in the subsurface. The objective of this research is to use several standard seismic post-stack inversion methods for reservo...

In the seismic inversion model, as the neural network algorithm there are some problems, the convergence bad, accuracy is not high. This paper presents a seismic inversion based on artificial fish Swarm Optimization neural network models. First to initialize fish mapping of chaos optimization and ergodicity of artificial fish-swarm search and adaptive strategies of artificial fish-swarm algorit...