Sharpness characterization of the 410 km upper mantle discontinuity by fixed scale singularity analysis of converted phases
نویسندگان
چکیده
Parametric waveform, monoand multiscale analyses methods are used to characterize the properties of the 410 discontinuity. The characterization involves the estimation of the sharpness, smoothness and extent of this transition from Pds converted phases. In our approach sharpness is no longer associated with the extent of the first-order discontinuity. Instead, the sharpness is related to the fractional order of a generalized transition, parametrized by this order and two additional parameters, expressing smoothing and extent/thickness length scales. Estimates for the parameters are derived by complementary parametric and direct scale analysis methods. Discontinuity characterization is used to construct a generalized transition model. This model is shown to accurately capture detailed information on the transition, which is necessary to obtain useful information on mineralogical changes that may occur at the 410 km transition.
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