Now showing items 1-20 of 30

    • A Bayesian framework for fracture characterization from surface seismic data 

      Zamanian, S. Ahmad; Fehler, Michael; Burns, Daniel R. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
      We describe a methodology for quantitatively characterizing the fractured nature of a hydrocarbon or geothermal reservoir from surface seismic data under a Bayesian inference framework. Fractures provide pathways for fluid ...
    • Data-Driven Estimation of the Sensitivity of Target-Oriented Time-Lapse Seismic Imaging to Source Geometry 

      Shabelansky, Andrey Hanan; Malcolm, Alison E.; Fehler, Michael (Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
      The goal of time-lapse imaging is to identify and characterize regions in which the earth's material properties have changed between surveys. This requires an effective deployment of sources and receivers to monitor the ...
    • Effect of borehole stress concentration on compressional wave velocity measurements 

      Fang, Xinding; Fehler, Michael; Cheng, Arthur (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      Formation elastic properties near a borehole may be altered from their original state due to the stress concentration around the borehole. This could lead to a biased estimation of formation elastic properties measured ...
    • Efficient characterization of uncertain model parameters with a reduced-order ensemble Kalman filter 

      Lin, Binghuai; McLaughlin, Dennis (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      Spatially variable model parameters are often highly uncertain and di fficult to observe. This has prompted the widespread use of Bayesian characterization methods that can infer parameter values from measurements of related ...
    • Efficient Double-Beam Characterization for Fractured Reservoir 

      Zheng, Yingcai; Fang, Xinding; Fehler, Michael; Burns, Daniel R. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2012-06)
      We proposed an efficient target-oriented method to characterize seismic properties of fractured reservoirs: the spacing between fractures and the fracture orientation. Based on the diffraction theory, the scattered wave ...
    • A field expansions method for scattering by periodic multilayered media 

      Malcolm, Alison E. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)
      The interaction of acoustic and electromagnetic waves with periodic structures plays an important role in a wide range of problems of scientific and technological interest. This contribution focuses upon the robust and ...
    • Finite Difference Elastic Wave Modeling Including Surface Topography 

      Al Muhaidib, Abdulaziz; Fehler, Michael; Toksoz, M. Nafi; Zhang, Yang (Massachusetts Institute of Technology. Earth Resources Laboratory, 2011)
      Surface topography and the weathered zone (i.e., heterogeneity near the earth’s surface) have great effects on elastic wave propagation. Both surface waves and body waves are contaminated by scattering and conversion by ...
    • Finite-Difference Simulations of Time Reversed Acoustics in a Layered Earth Model 

      Lu, Rongrong; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2007)
      Traditionally an earthquake is located by using the arrival times of P and S phases. This uses only a limited portion of the information on a seismogram. A large part of the information carried by the waveform is not used. ...
    • Frequency-Domain Finite-Difference Acoustic Modeling with Free Surface Topography using Embedded Boundary Method 

      Li, Junlun; Zhang, Yang; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)
      In this paper, we present a method to model acoustic wave propagation in the frequencydomain in the presence of free surface topography using the embedded boundary method. The advantage of this method is to solve for the ...
    • High-dimensional wave atoms and compression of seismic datasets 

      Leinonen, Matti; Hewett, Russell J.; Zhang, Xiangxiong; Ying, Lexing; Demanet, Laurent (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      Wave atoms are a low-redundancy alternative to curvelets, suitable for high-dimensional seismic data processing. This abstract extends the wave atom orthobasis construction to 3D, 4D, and 5D Cartesian arrays, and parallelizes ...
    • In Situ, Nonlinear Soil Response Applying an Active Source 

      Johnson, Paul; Toksoz, M. Nafi; Morgan, Frank Dale; Pearce, Fred (Massachusetts Institute of Technology. Earth Resources Laboratory, 2009)
      Soil sites have a profound effect on ground motion during earthquakes due to their low wave speeds, layered structure, and nonlinear constitutive relationship. Measurements of nonlinear soil response under natural ...
    • Joint flow-seismic inversion for characterizing fractured reservoirs: theoretical approach and numerical modeling 

      Kang, Peter K.; Zheng, Yingcai; Fang, Xinding; Wojcik, Rafal; McLaughlin, Dennis; e.a. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      Traditionally, seismic interpretation is performed without any account of the flow behavior. Here, we present a methodology to characterize fractured geologic media by integrating flow and seismic data. The key element of ...
    • Modeling of acoustic wave scattering from a two-dimensional fracture 

      Chen, Tianrun; Fehler, Michael; Brown, Stephen; Zhang, Yang; Fang, Xinding; e.a. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)
      In this paper, we model the acoustic scattering from a two dimensional fracture that is simulated by two different physical models. We calculate the scattering from the fractures with different properties based on these ...
    • Nonlinear Frechet derivative and its De Wolf approximation 

      Wu, Ru-Shan; Zheng, Yingcai (Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
      We introduce and derive the nonlinear Frechet derivative for the acoustic wave equation. It turns out that the high order Frechet derivatives can be realized by consecutive applications of the scattering operator and a ...
    • Numerical modeling of elastic wave scattering by near-surface heterogeneities 

      Al Muhaidib, Abdulaziz; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      A perturbation method for elastic waves and numerical forward modeling are used to calculate the effects of seismic wave scattering from arbitrary shape shallow subsurface heterogeneities. Wave propagation is simulated ...
    • Numerical Modeling of Transport Properties and Comparison to Laboratory Measurements 

      Smith, Wave; Zhan, Xin; Schwartz, Larry; Morgan, Frank Dale; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2008-06-10)
      Transport properties, such as permeability and electrical conductivity, are important in many geophysical and petroleum applications. The microstructure of a porous medium and physical characteristics of the solid and ...
    • A Numerical Study of the Effects of Wave-Induced Fluid Flow in Porous Media: Linear Solver 

      Zhang, Yang; Song, Limin; Deffenbaugh, Max; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2009)
      In this paper, we present a computational method to simulate wave propagation in porous rocks saturated with Newtonian fluids over a range of frequencies of interest. The method can use a digital representation of a rock ...
    • One-Way Wave Propagators For Velocity Analysis On Curvilinear Coordinates 

      Budkick, Scott; van der Hilst, Robert D.; de Hoop, Maarten V. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2008)
      Due to present computational limitations, migration by the one-way wave equation remains an integral tool in seismic exploration. For the realistic interpretation of common image point gathers, it is necessary that migration ...
    • Pore Scale Modeling of Rock Properties and Comparison to Laboratory Measurements 

      Zhan, Xin; Schwartz, Larry; Smith, Wave; Toksoz, M. Nafi; Morgan, Frank Dale (Massachusetts Institute of Technology. Earth Resources Laboratory, 2009)
      The microstructure of a porous medium and the physical characteristics of the solid and fluid phases determine the macroscopic transport properties of the medium. The purpose of this paper is to test numerical calculations ...
    • Real-time ensemble control with reduced-order modeling 

      Lin, Binghuai; McLaughlin, Dennis (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      The control of spatially distributed systems is often complicated by significant uncertainty about system inputs, both time-varying exogenous inputs and time-invariant parameters. Spatial variations of uncertain parameters ...