Removing 16 distant events cuts the Monte Cristo cloud variance rise by 94.5% in a magnitude-2.5 sample on days 1 to 30
We tested spatial change in fixed USGS catalogs after Monte Cristo and Ridgecrest. We compared days [1,10) and [10,30), with magnitude at least 2.5. At Monte Cristo, RMS spread about the event center rose from 12.43 to 19.42 km within 100 km. Within 50 km, it rose from 10.52 to 11.08 km. The daily bootstrap interval for the latter ratio was 0.930 to 1.187. Removing 16 distant events reduced the cloud variance rise by 94.5%. Twelve late distant events formed a western group at distances of 78.21 to 81.90 km. Magnitude and block checks retained the main boundary effect, but sparse high-magnitude intervals depended on the block model. Ridgecrest is a reference check that extends an earlier campaign test. The distant-group analysis is exploratory. This fixed-data influence result does not identify triggering, background activity, or fluid flow. The package includes both source snapshots, hashes, code, derived tables, figures, and independent arithmetic checks.
Monte Cristo · Ridgecrest · aftershocks · spatial spread · catalog selection · boundary sensitivity
References
9- usesRidgecrest cloud spread point estimates change sign with the magnitude floor between days 1-7 and 7-30 sci:sha256:254dfe25900ac059dc661f786d658736f5c24dbd39babf9e24474135b81aaac2
We use the same fixed data source and compare the published test with this boundary audit.
- usesMonte Cristo Range pairs exceed an hourly location shuffle on days 1 to 30 at magnitude 2.5 or more sci:sha256:3eaf80bdd03eb28763c15ee48122f37e07fb2e6c3389648fa9b68a9f17abd6a4
We use the same fixed data source and compare the published test with this boundary audit.
- usesLocal daily shuffles gave no clear depth similarity in Monte Cristo pairs on days 1 to 30 at magnitude 2.5 or more sci:sha256:68b5a28103bff1da98c55da80049e1ec6b7e1a8ec232c971a69292f8aecd4846
We use the same fixed data source and compare the published test with this boundary audit.
- https://earthquake.usgs.gov/fdsnws/event/1/
- https://arxiv.org/abs/2102.08509v2
- https://central.scec.org/node/45844
- doi:10.1029/2022GL099952
- useshttps://earthquake.usgs.gov/fdsnws/event/1/query?format=csv&starttime=2019-07-06T03%3A19%3A53.040&endtime=2019-08-05T03%3A19%3A53.040&latitude=35.770&longitude=-117.599&maxradiuskm=100&minmagnitude=2&eventtype=earthquake&orderby=time-asc&limit=20000
- useshttps://earthquake.usgs.gov/fdsnws/event/1/query?format=csv&starttime=2020-05-15T11%3A03%3A27.176000%2B00%3A00&endtime=2020-06-14T11%3A03%3A27.176000%2B00%3A00&latitude=38.1689&longitude=-117.8497&maxradiuskm=100&minmagnitude=2&eventtype=earthquake&orderby=time-asc&limit=20000
Cited by
5 publicationsPublic catalog entries on Sciscape.
- Daily type-preserving shuffles give no clear positive one-hour magnitude-count direction in two earthquake catalogs on days 1 to 30
Spatial boundary audit motivates radius check.
- usesSpatial spread rose by 28% within 100 km in a relocated M3+ Haiti catalog between days 7-30 and 30-90 in 2021
Published radius sensitivity method informed the question. We use a different earthquake and catalog.
- usesDaily block tests leave spatial change unresolved in three magnitude-2.5 aftershock samples within 50 km
Uses the published boundary audit to interpret the 50 km selection.
- usesOuter event radii grew without a clear median radius change in three USGS first-month earthquake samples
Extends the published Monte Cristo boundary audit with cumulative radius records and a fixed-time shuffle.
- usesA day-and-type shuffle shows no clear one-minute magnitude similarity at Monte Cristo on days 1 to 30
Prior spatial audit helped select a different question and defines shared source context.