In this article, we compare field estimates of near‐surface attenuation, as captured by site‐specific κ‐values (i.e., κ0) with laboratory‐based estimates of minimum shear‐strain damping (ξmin). We propose models for ξmin based on κ0 measured at selected stations of the KiK‐net database, which are found to be generally larger than low‐strain damping values obtained from laboratory testing. The latter can only quantify intrinsic material damping, whereas other attenuation mechanisms such as scattering of the wavefield contribute to field‐based estimates. In addition, we evaluate the difference in damping at the surface and at borehole stations to determine the contribution of shallow layers to attenuation as captured by κ0‐values at the surface. Thus, values of κ0 are computed at the surface and at the downhole instrument depth. The difference between both values, Δκ, correlates well with the averaged shear‐wave velocity over the top 30 m of the profile, VS30, and with the depth to bedrock. Estimates of κ0 for hard‐rock and stiff sites in Japan are also examined and compared with other regional κ0‐values proposed for high VS30 materials in New Zealand, Greece, and Switzerland. Two values of κ0, which are lower than the corresponding estimates for the aforementioned regions, are deemed potential descriptors of hard‐rock conditions in Japan. The ability of the proposed κ0‐consistent damping models to predict ground motions using the vertical array data from the KiK‐net sites has yet to be tested.

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