start-ver=1.4
cd-journal=joma
no-vol=53
cd-vols=
no-issue=
article-no=
start-page=e2026GL122541
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2026
dt-pub=20260520
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Discovery of Repeating Shallow Moonquakes in the Apollo Lunar Seismic Data
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Shallow moonquakes have been considered unique due to their large magnitudes and affinities with intraplate earthquakes. However, the small number of detections (<80 events) has prevented detailed characterization. In this study, I identified a pair of repeating shallow moonquakes by analyzing a recently updated moonquake data set. Relative-phase assessment revealed that these events exhibit a consistent fault-slip direction despite their occurrence at opposite tidal phases. This differs from what was observed for repeating deep moonquakes, which are closely related to tides, implying that tidal stress does not dominantly control fault-slip initiation of the repeating shallow moonquakes. Also, the identified repeating shallow moonquakes exhibit a similar relationship between seismic moment and the spatial scale of the slip area to earthquakes. This may indicate that earthquake-like fault physics operates on the Moon, albeit with a different driving mechanism than on Earth.
en-copyright=
kn-copyright=

en-aut-name=OnoderaKeisuke
en-aut-sei=Onodera
en-aut-mei=Keisuke
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

affil-num=1
en-affil=Institute for Planetary Materials, Okayama University
kn-affil=
en-keyword=lunar  seismology    
kn-keyword=lunar  seismology    
en-keyword=tectonism
kn-keyword=tectonism
en-keyword=Moon
kn-keyword=Moon
en-keyword=Apollo
kn-keyword=Apollo
en-keyword=planetary seismology
kn-keyword=planetary seismology
en-keyword=fault physics
kn-keyword=fault physics
END