Buuxi weedhan soo socota: Sababtoo ah taariikhda ay ku abuurtay dhulgariirro waaweyn (1857, 1906) barta diiradda lagu saarayo qiimeynta khatarta dhulgariirka ee California waxay ahayd nidaamka San Andreas ee khalkhalgelinta. Si kastaba ha noqotee, nidaamka khaladaadka, oo ay ku jiraan Sierra Madre <unk> Cucamonga Fault System oo ku teedsan xadka San Gabriel iyo San Fernando Valleys, ayaa sidoo kale sababay taxane dhacdooyin dhexdhexaad ah ilaa waaweyn oo ka dhacay Aagga Weyn ee Los Angeles. Qeybta ugu galbeed badan ee nidaamkan qalloocan ayaa dillaacay sanadkii
1971 waxaana loo aqoonsaday mid ka mid ah lixda qaladaad ee ugu waawayn ee halis ku ah gobolkan dadku ku badan yihiin.