Bulletin of the Seismological Society of America; April 2005; v. 95; no. 2;
p. 540-548; DOI: 10.1785/0120030250
© 2005 Seismological Society of America
Application of Kriging Technique to Seismic Intensity Data
Valerio De Rubeis1,
Patrizia Tosi1,
Calvino Gasparini1 and
Alessandro Solipaca2
1 Istituto Nazionale di Geofisica e
Vulcanologia
Via di Vigna Murata, 605
I-00143 Roma,
Italy
(V.DeR., P.T., C.G.)
2 Istituto Nazionale di
Statistica
Ufficio Regionale
Viale Liegi, 13
I-00198 Roma,
Italy
(A.S.)
Spatial analysis, involving experimental semivariogram evaluation and kriging
interpolation, is performed on macroseismic intensity data assumed to represent
a regionalized variable. A semivariogram is modeled, showing that data
components act at different scale levels. Interpretation of the semivariogram in
terms of fractal dimension allows separation of the error component from other
scale-dependent components. Use of an objective best spatial-range determination
for filtering eliminates the subjective choice that is usually based on
data-sampling density, permitting the reconstruction of the smoothed
interpolated intensity field. Results are given together with error estimation
due to local variability and sampling-density distribution. The method is first
applied to synthetic macroseismic data with controlled variable error content
and sampling density: the ability to rebuild the original, error-free intensity
field is demonstrated. Then macroseismic data from an Italian medium-intensity
earthquake are analyzed and spatial intensity attenuation re-evaluated.
Copyright © 2009 by Seismological Society of America