A volcanic earthquake with Mw 5:6 occurred beneath the Bárdarbunga caldera in Iceland on 29 September 1996. This earthquake is one of a decade-long sequence ofM 5 events at Bárdarbunga with non-double-couple mechanisms in the Global Centroid Moment Tensor catalog. Fortunately, it was recorded well by the regional-scale Iceland Hotspot Project seismic experiment. We investigated the event with a...

Consider an open set D ⊆ R, equipped with a probability measure μ. An important characteristic ofa smooth function f : D→ R is its second-moment matrix Σμ :=́ ∇f(x)(∇f(x))∗μ(dx) ∈ Rn×n, where∇f(x) ∈ R is the gradient of f(·) at x ∈ D. For instance, the span of the leading r eigenvectors of Σμforms an active subspace of f(·), thereby extending the concept of principal componen...

-The fault parameters of the Guam earthquake of August 8, 1993 are estimated from seismological analyses, and the possibility of identifying the actual fault plane from tsunami waveforms is tested. The Centroid Moment Tensor solution of long-period surface waves shows one nodal plane shallowly dipping to the north and the other nodal plane steeply dipping to the south. The seismic moment is 3.5...

Using a regional time-domain waveform inversion for the complete moment tensor we calculate the deviatoric and isotropic source components for several explosions at the Nevada Test Site (NTS) as well as earthquakes, and collapses in the surrounding region of the western U.S. The events separate into specific populations according to their deviation from a pure double-couple and ratio of isotrop...