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A unified perspective of seismicity and fault coupling along the San Andreas Fault.

ABSTRACT: The San Andreas Fault (SAF) showcases the breadth of possible earthquake sizes and occurrence behavior; in particular, the central SAF is a microcosm of such diversity. This section also exhibits the spectrum of fault coupling from locked to creeping. Here, we show that the observations of aseismic slip, temporal clustering of seismicity, and spatial variations in earthquake size distributions are tightly connected. Specifically, the creep rate along the central SAF is shown to be directly proportional to the fraction of nonclustered earthquakes for the period 1984-2020. This relationship provides a unified perspective of earthquake phenomenology along the SAF, where lower coupling manifests in weaker temporal clustering, with repeating earthquakes as an end-member. This new paradigm provides additional justification for characterizing the northwest ∼75 kilometers of the creeping segment as a transition zone, with potential implications for seismic hazard.

SUBMITTER: Liu YK

PROVIDER: S-EPMC8865773 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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A unified perspective of seismicity and fault coupling along the San Andreas Fault.

Liu Yuan-Kai YK Ross Zachary E ZE Cochran Elizabeth S ES Lapusta Nadia N

Science advances 20220223 8

The San Andreas Fault (SAF) showcases the breadth of possible earthquake sizes and occurrence behavior; in particular, the central SAF is a microcosm of such diversity. This section also exhibits the spectrum of fault coupling from locked to creeping. Here, we show that the observations of aseismic slip, temporal clustering of seismicity, and spatial variations in earthquake size distributions are tightly connected. Specifically, the creep rate along the central SAF is shown to be directly propo ...[more]

PMID: 35196076

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