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We implement a method to invert jointly teleseismic P‐wave receiver functions and surface wave group and phase velocities for a mutually consistent estimate of earth structure. Receiver functions are primarily sensitive to shear wave velocity contrasts and vertical traveltimes, and surface wave dispersion measurements are sensitive to vertical shear wave velocity averages. Their combination may bridge resolution gaps associated with each individual data set. We formulate a linearized shear velocity inversion that is solved using a damped least‐squares scheme that incorporates a priori smoothness constraints for velocities in adjacent layers. The data sets are equalized for the number of data points and physical units in the inversion process. The combination of information produces a relatively simple model with a minimal number of sharp velocity contrasts. We illustrate the approach using noise‐free and realistic noise simulations and conclude with an inversion of observations from the Saudi Arabian Shield. Inversion results for station SODA, located in the Arabian Shield, include a crust with a sharp gradient near the surface (shear velocity changing from 1.8 to 3.5 km s−1 in 3 km) underlain by a 5‐km‐thick layer with a shear velocity of 3.5 km s−1 and a 27‐km‐thick layer with a shear velocity of 3.8 km s−1, and an upper mantle with an average shear velocity of 4.7 km s−1. The crust–mantle transition has a significant gradient, with velocity values varying from 3.8 to 4.7 km s−1 between 35 and 40 km depth. Our results are compatible with independent inversions for crustal structure using refraction data.

A review of a moment tensor for describing a general seismic point source is presented to show a second order moment tensor can be related to simpler seismic source descriptions such as centers of expansion and double couples. A review of literature is followed by detailed algebraic expansions of the moment tensor into isotropic and deviatoric components. Specific numerical examples are provided in the appendices for use in testing algorithms for moment tensor decomposition.

A contour map of crustal Q0 values for the entire United States is presented based on a scattering model to explain the coda waves of local and near regional earthquakes. These coda Qo values are in good agreement with Q of Lg waves. Data are obtained from over 250 local earthquakes, with most magnitudes between 3.0 and 5.0, recorded by 25 WWSSN and 27 LRSM stations throughout the continental United States. These two sets of data provide a range of frequencies from 0.5 to 3.5 Hz. A frequency dependence of Q is observed in the range of frequencies considered. A power law dependence of the form Q = Qo(f/fo) • is assumed. The value of frequency dependence r/, is found to be maximum in the tectonically active western United States and least in the stable regions of the central and south central United States. The lowest Q0 values are obtained in the western United States, with values ranging from 140 to 200 in the Coastal Plains. Average crustal Qo values for the Basin and Range province vary from 200 to 300, increasing gradually to 400 in the Colorado Plateau region. Qo values in the Columbia Plateau vary from 200 to 400. Qo values increase very rapidly along the central and southern Rocky Mountains from 400 to 800. East of the Rocky Mountains Q0 values increase gradually in the Interior Plains to a maximum value of around 1300 in the Mississippi Embayment region. Farther east Qo values decrease gradually to an almost constant value of 1000 along the Appalachian Mountains. Coastal regions of eastern and northeastern United States have a crustal Q0 value between 900 to 700. Regions of north central and Gulf Coastal Plains show low Qo values, ranging from 600 to 400 and less. The source factor B(fp), a measure of the intensity of scattering, was obtained for several different regions of the continental United States. Regions of high Q0 values exhibit low i.ntensity of scattering. INTRODUCTION As a result of several geophysical investigations during the last two decades, the existence of lateral variations of some important geophysical properties in the crust and upper mantle has been well established. One of these quantities is the rate of anelastic attenuation of seismic waves. Recent studies indicate that there are strong lateral variations of seismic anelasfic attenuation beneath the continental United States. It is now generally accepted that seismic anelastic attenuation is high in the western United States and low in the central and eastern United States. However, detailed short-period attenuation observations over short paths within individual geological provinces of the continental United States are lacking. As early as 1962, Romney et al. [1962] noticed that Pn and Lq waves from the GNOME explosion appeared to attenuate more rapidly along paths to the west of the test site than along paths to the east. Sutton et al. 1'1967] measured Q of shortperiod Pq and Lq phases appropriate for the crust and upper mantle. Their values for Q varied from 200 in the western United States to 1000 in east central United States...