Now showing items 245-264 of 456

    • Interferometric imaging of multiples in an RTM approach 

      Malcolm, Alison E.; de Hoop, Maarten V. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)
      It is well known that reverse-time migration is capable of correctly imaging multiply scattered energy. To do this, one of the interfaces from which the waves scatter must be included in the background velocity model. ...
    • Interval Attenuation Estimation 

      Alshammery, Hafiz J.; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 1998)
      The goal of this paper is to study the accuracy of estimating the Quality Factor (Q) from ultrasonic pre-stack P-wave reflection data. Q is estimated by applying the spectral ratio method to the top and bottom reflections ...
    • Inversion For Permeability From Stoneley Wave Velocity And Attenuation 

      Cheng, N. Y.; Cheng, C. H.; Toksoz, M. N. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)
      The in situ permeability of a formation is obtained by the inversion of Stoneley wave phase velocity and attenuation, which are evaluated by applying the Extended Prony's method to the array sonic logging data. The Maximum ...
    • Inversion of Borehole Guided Wave Amplitudes for Formation Shear Wave Attenuation Values 

      Burns, D. R.; Cheng, C. H. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
      A linear least squares inversion, based on analytic partition coefficient expressions, is developed to estimate the fluid and formation shear wave Q values from spectral ratio measurements-of the guided wave arrivals of ...
    • Inversion of Shear Wave Anisotropic Parameters in Strongly Anisotropic Formations 

      Chi, Shihong; Tang, Xiaoming; Zhu, Zhenya (Massachusetts Institute of Technology. Earth Resources Laboratory, 2006)
      Deepwater reservoirs use highly deviated wells to reduce cost and enhance hydrocarbon recovery. Due to the strong anisotropic nature of many of the marine sediments, anisotropic seismic imaging and interpretation can improve ...
    • Inversion Of Travel Time For Velocity 

      Willis, M.E. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)
      Common source velocities and borehole compensated (BC) estimates have been used to obtain formation velocity estimates from full waveform acoustic logs (Willis and Toksoz, 1982). With both of these methods the ...
    • Inversion of Travel Time for Velocity Using Multi-Spacing Sonic Tools 

      Paternoster, Benoit J. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1985)
      Spatial resolution of sonic logs is greatly affected by the minimum spacing between receivers. Improvements can be made, however, when the spatial sampling of the formation is less than the minimum spacing. This paper ...
    • 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 ...
    • Joint microseismic event location with uncertain velocity 

      Poliannikov, Oleg V.; Prange, Michael; Malcolm, Alison E.; Djikpesse, Hugues (Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
      We study the problem of the joint location of seismic events using an array of receivers. We show that locating multiple seismic events simultaneously is advantageous compared to the more traditional approaches of locating ...
    • Kinematic redatuming by two source interferometry 

      Poliannikov, Oleg V. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2010-04-26)
      Interferometry is a method of redatuming physical sources to receiver locations. Under idealized assumptions stacking the cross correlogram of the two common receiver gathers yields a bandlimited Green's function between ...
    • Laboratory Borehole Model 

      Shortt, E. R. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1986)
      An experimental method for acquisition offull waveform acoustic logging (FWAL) data from scaled laboratory borehole/formation models is under development. A spark-gap source, fabricated in the lab, is used in conjunction ...
    • Laboratory Measurements of Attenuation in Rocks at Ultrasonic Frequencies 

      Gonguet, Christophe; Coyner, Karl B.; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 1985)
      The spectral ratio method is used to calculate the quality factor (Q) in porous rock samples at ultrasonic frequencies (0.3 - 1.5 MHz). The data were collected using the pulse transmission technique with aluminum used ...
    • Laboratory Studies Of The Acoustic Properties Of Samples From The Salton Sea Scientific Drilling Project And Their Relation To Microstructure And Field Measurements 

      Tarif, P. A.; Wilkens, R. H.; Cheng, C. H.; Paillet, F . L. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)
      Compressional and shear wave velocities were measured at confining pressures up to 200 MPa for twelve core samples from the depth interval of 600 to 2600 m in the California State 2-14 borehole. Samples were selected to ...
    • Laboratory Study Of Frequency Dependent Streaming Potentials 

      Reppert, Philip M.; Morgan, F. Dale (Massachusetts Institute of Technology. Earth Resources Laboratory, 1998)
      Frequency dependent streaming potentials were measured on a glass capillary, porous filter, and a sample of Boise sandstone. The pore diameters for these three samples range from 1 millimeter to 34 micrometers. The ...
    • Lithologic Cycles And Paleo Fluid Flow Channels In Old Oceanic Crust From Geophysical Logs At ODP Site 418A 

      Burns, D. R.; Thompson, D. R.; Cheng, C. H. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)
      Using some new processing of the multichannel sonic (MCS) log data from Site 418A, the resulting P, S, and Stoneley wave velocity estimates and apparent attenuation were integrated with the natural gamma, spectral gamma, ...
    • A locally conservative variational multiscale method for the simulation of porous media flow with multiscale source term 

      Juanes, Ruben; Dub, Francois-Xavier (Massachusetts Institute of Technology. Earth Resources Laboratory, 2008)
      We present a variational multiscale mixed finite element method for the solution of Darcy flow in porous media, in which both the permeability field and the source term display a multiscale character. The formulation ...
    • Locating point diffractors in layered media by spatial dynamics 

      Poliannikov, Oleg V. (Massachusetts Institute of Technology. Earth Resources Laboratory, 2008-06-16)
      We present a new approach to the problem of detecting point diffractors from active source surface seismic data. We formulate an optimization problem in the configuration space of possible collections of scatterers and ...
    • Location Of Microearthquakes Induced By Hydraulic Fracturing 

      Rodi, William; Li, Yingping; Cheng, C. H. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1993)
      This paper examines the problem of locating microearthquakes induced by hydraulic fracturing using seismic arrival time data. In addition to the use of absolute arrival times measured for individual events, we consider ...
    • Logging in Multilayered Saturated Porous Formations 

      Schmitt, D. P.; Cheng, C. H.; Toksoz, M. N. (Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
      We present a general formulation based on the Thomson-Haskell method which allows the study of complex models. The surrounding formation may be composed of several coaxial porous shells or of a combination of both porous ...
    • Measured radiation patterns of the scale model dipole tool 

      Lu, Rongrong; Rao, Rama V. N.; Toksoz, M. Nafi (Massachusetts Institute of Technology. Earth Resources Laboratory, 2003)
      The sound field of finite dipole acoustic transducers in a steel tool was investigated and their horizontal by measuring their vertical radiation patterns in water at two different frequencies. Measurements were also made ...