1966: Ph.D., California Institute of Technology
1962: M.S., University of Minnesota, Minneapolis
1960: B.S., University of Minnesota, Minneapolis 

Use of geophysical methods to study structure and processes within the earth, ranging from global scales to environmental studies of the shallow subsurface. Study of seismic sources, including both earthquakes and explosions, with particular application to the monitoring of nuclear test ban treaties. Development of improved theoretical and computational methods of treating wave propagation in realistic earth models. Application of inverse methods to geophysical problems.

Pulliam, R. J., D. W. Vasco, L. R. Johnson, Tomographic inversions for mantle P-wave velocity based on the minimization of l2 and l1 norms of ISC travel time residuals, J. Geophys. Res., 98, 699-734, 1993.

Vasco, D. W., R. J. Pulliam, L. R. Johnson, Formal inversion of ISC arrival times for mantle P-velocity structure, Geophys. J. Int., 113, 586-606, 1993.

Tura, M. A. C., L. R. Johnson, A stable method for linearized inversion of elastic parameters, Geophys. J. Int., 115, 1-13, 1993.

Korneev, V. A., L. R. Johnson, Scattering of elastic waves by a spherical inclusion - I. Theory and numerical results, Geophys. J. Int., 115, 230-250, 1993.

Korneev, V. A., L. R. Johnson, Scattering of elastic waves by a spherical inclusion - II. Limitations of asymptotic solutions, Geophys. J. Int., 115, 251-263, 1993.

Vasco, D. W., L. R. Johnson, and E. L. Majer, Ensemble inference in geophysical inverse problems, Geophys. J. Int., 115, 711-728, 1993.

Stump, B. W., R. E. Reinke, K. H. Olsen, L. R. Johnson, Isotropic and deviatoric characterization of the Coalora nuclear explosion in Yucca Flats, Geophys. J. Int., 116, 538-552, 1994.

Vasco, D. W., L. R. Johnson, R. J. Pulliam, P. S. Earle, Robust inversion of IASP91 travel time residuals for mantle P and S velocity structure, earthquake mislocations, and station corrections, J. Geophys. Res., 99, 13,727-13,755, 1994.

Johnson, L. R., Seismic source parameters, in Proceedings of the Symposium on the Non-Proliferation Experiment, M. D. Denny (ed), Lawrence Livermore National Laboratory, Livermore, CA, CONF-9404100, pages 6.3-6.18, 1994.

Gritto, R., V. A. Korneev, L. R. Johnson, Low frequency elastic wave scattering by an inclusion - limits of applications, Geophys. J. Int., 120, 677-692, 1995.

Vasco, D. W., L. R. Johnson, R. J. Pulliam, Lateral variations in mantle velocity structure and discontinuities determined from P, PP, S, SS, and SS-SdS travel time residuals, J. Geophys. Res., 24,037-24,059, 1995.