Oakland, California Oakland to consistently be listed as one of America's most crime-ridden cities. In 1980 Oakland's black population reached its 20th-century peak at approximately 47% of the overall city population. The 6.9 Loma Prieta earthquake occurred on October 17, 1989. The rupture was related to the San Andreas fault system and affected the entire San Francisco Bay Area with a maximum Mercalli intensity of IX ("Violent"). Many structures in Oakland were badly damaged including the double-decker portion of Interstate 880 that collapsed. The eastern span of the San Francisco–Oakland Bay Bridge also sustained damage and was closed to traffic for one
Earthquake prediction of having observed such phenomena prior to an earthquake, no such phenomena has been shown to be an actual precursor. A 2011 review found the "most convincing" electromagnetic precursors to be ULF magnetic anomalies, such as the Corralitos event (discussed below) recorded before the 1989 Loma Prieta earthquake. However, it is now believed that observation was a system malfunction. Study of the closely monitored 2004 Parkfield earthquake found no evidence of precursory electromagnetic signals of any type; further study showed that earthquakes with magnitudes less than 5 do not produce significant transient signals. The "International Commission on Earthquake Forecasting for