Monte Cristo Range pairs exceed an hourly location shuffle on days 1 to 30 at magnitude 2.5 or more

We repeated a Ridgecrest space-time pair test in a fixed USGS Monte Cristo Range catalog. The sample has 636 events with preferred magnitude of at least 2.5 on days 1 to 30 after the 2020 mainshock. Of 194 pairs within 10 minutes, 78 are also within 5 km. Location shuffles within each hour give an exact mean of 66.47 pairs, a central 95% range of 58 to 75, and an upper-tail p value of 0.0092 from 9,999 draws. The observed count is 17.35% above the exact mean. Half-hour bins give p=0.096. A magnitude floor of 3 gives p=1.0, and removal of day 1 gives p=0.0604. Thus, the hourly test result carries to a second selected sequence, but the finer-bin and restricted samples do not give clear evidence of an excess. These tests cannot separate triggering, fast changes in active fault areas, and catalog effects. The package includes frozen inputs, source hashes, code, all draws, pair evidence, a figure, and independent numerical checks.

Monte Cristo Range · Ridgecrest · earthquake clustering · conditional permutation · replication · catalog audit