S U M M A R Y The seismic moment tensors for certain types of sources, such as volcanic earthquakes and nuclear explosions are expected to contain an isotropic component. Some earlier efforts to calculate the isotropic component of these sources are flawed due to an error in the method of Jost & Herrmann. We corrected the method after Herrmann & Hutchensen and found great improvement in the rec...

Abstract Coseismic rotations of principal stress axes can provide insights into the strength crust, but it is unclear how common this phenomenon is. We use a nearest‐neighbor clustering algorithm to identify earthquake sequences in global ISC‐GEM catalog and regional Southern California catalog. Using an inner‐product‐based pairwise measure moment tensor similarity, we demonstrate that, both ca...

With the present study we introduce a fast and robust method to calculate source displacement spectra of small earthquakes on local regional scale. The work is based publicly available Qopen full envelope inversion which further tuned for given purpose. Important parameters -- seismic moment, moment magnitude, corner frequency high-frequency fall-off are determined from by fitting simple earthq...

The potential for using seismograms in a linear inversion process to recover the seismic moment tensor has been theorized for sometime. Unfortunately, practical application of the theory is difficult. Lateral variations of the Earth and imprecise knowledge of the source often severely contaminate real seismic data relative to synthetic models which must be supplied. This paper outlines an exper...

In this paper the connection between the dipole moment tensor D and the spin four-tensor S is formulated in the form of the generalized UhlenbeckGoudsmit hypothesis, D = gSS . It is also found that the spin four-tensor S can be decomposed into two 4-vectors, the usual “space-space” intrinsic angular momentum S, which will be called ‘magnetic’ spin (mspin), and a new one, the “time-space” intrin...

The seismic moment and source orientation of the 8 November 1980 Eureka, California, earthquake (Ms = 7.2) are determined using long-period surface and body wave data obtained from the SRO, ASRO, and IDA networks. The favorable azimuthal distr ibution of the recording stations allows a well-constrained mechanism to be determined by a simultaneous moment tensor inversion of the Love and Rayleigh...