Dataset Information

Rare Occurrences of Non-cascading Foreshock Activity in Southern California.

ABSTRACT: Earthquakes preceding large events are commonly referred to as foreshocks. They are often considered as precursory phenomena reflecting the nucleation process of the main rupture. Such foreshock sequences may also be explained by cascades of triggered events. Recent advances in earthquake detection motivates a reevaluation of seismicity variations prior to mainshocks. Based on a highly complete earthquake catalog, previous studies suggested that mainshocks in Southern California are often preceded by anomalously elevated seismicity. In this study, we test the same catalog against the Epidemic Type Aftershock Sequence model that accounts for temporal clustering due to earthquake interactions. We find that 10/53 mainshocks are preceded by a significantly elevated seismic activity compared with our model. This shows that anomalous foreshock activity is relatively uncommon when tested against a model of earthquake interactions. Accounting for the recurrence of anomalies over time, only 3/10 mainshocks present a mainshock-specific anomaly with a high predictive power.

SUBMITTER: Moutote L

PROVIDER: S-EPMC8243970 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Rare Occurrences of Non-cascading Foreshock Activity in Southern California.

Moutote L L Marsan D D Lengliné O O Duputel Z Z

Geophysical research letters 20210407 7

Earthquakes preceding large events are commonly referred to as foreshocks. They are often considered as precursory phenomena reflecting the nucleation process of the main rupture. Such foreshock sequences may also be explained by cascades of triggered events. Recent advances in earthquake detection motivates a reevaluation of seismicity variations prior to mainshocks. Based on a highly complete earthquake catalog, previous studies suggested that mainshocks in Southern California are often preced ...[more]

PMID: 34219839

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Dataset Information

Rare Occurrences of Non-cascading Foreshock Activity in Southern California.

Publications

Rare Occurrences of Non-cascading Foreshock Activity in Southern California.

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