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Comment: 15:03 - 16:20 (01:17)
Source: Annenberg/CPB Resources - Earth Revealed - 25. Living With Earth, Part I
Keywords: "Loma Prieta Earthquake", earthquake, magnitude, "San Francisco Earthquake", "San Francisco", "Marina District"
Our transcription: As terrifying as this tremor was, geologists call it a "moderate" rather than a "great" earthquake.
The magnitude of the 1906 quake, which also shook the San Francisco Bay region, has been estimated at 8.3 meaning it released about 60 times more energy than the Loma Prieta quake.
Nonetheless, there is a chilling irony that links the two events.
When California staged an international exposition in 1915, the City of San Francisco wanted to divert world attention from the devastating quake that had rocked the area nine years earlier.
In so doing, it hoped to market itself as a viable Pacific port.
This led to the building of exposition structures in the Marina district.
The materials selected to fill in the shallow water of the marina were a combination of rubble from the 1906 quake, and un-compacted mud and sand.
Seventy-four years later, this community built atop the rubble of one earthquake would suffer catastrophe from another.
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