The Overlap of Aftershock Coda Waves and Short‐Term Postseismic Forecasting. Issue 7 (4th July 2018)

• Record Type: Journal Article
• Authors: de Arcangelis, L.; Godano, C.; Lippiello, E.
• Is Part Of: Journal of geophysical research. Volume 123:Issue 7(2018)
• Page Start: 5661
• Page End: 5674
• Publication Date: 2018-07-04
• Subjects: forecasting -- catalog incompleteness -- aftershocks -- ETAS model; Geomagnetism -- Periodicals; Geochemistry -- Periodicals; Geophysics -- Periodicals; Earth sciences -- Periodicals; 551.1
• DOI: 10.1029/2018JB015518
• Languages: English
• ISSNs: 2169-9313

Abstract

Abstract: The elaboration of reliable forecasting in the first hours after large shocks, very useful for the postseismic management, is strongly affected by the huge incompleteness of seismic catalogs. The deficit of observed events, in the first part of aftershock sequences, can be naturally attributed to different mechanisms such as the inefficiency of the seismic network as well as the overlap of seismic records. In this study we show that short‐term aftershock incompleteness can be explained only in terms of the second mechanism whereas it is only weakly affected by the quality of the instrumental coverage. Indeed, we show that larger deviations from the Gutenberg‐Richter law and the Omori‐Utsu law can be found in regions with a higher seismic network efficiency. We use these results to develop an incomplete Epidemic‐Type Aftershock Sequence model able to reproduce statistical features in time and magnitude of recorded aftershocks. Key Points: We show that postseismic aftershock incompleteness is higher in regions where the seismic network presents a higher density of stations The temporal statistical features of aftershocks are reproduced interpreting incompleteness in terms of the overlap of coda waves We propose a generalization of the ETAS model, useful for aftershock forecasting, that incorporates time‐dependent incompleteness