Map showing epicenter (green dot) of magnitude-3.9 earthquake near Morgan Hill. The quake probably struck on a subsidiary of the Calaveras Fault. Credit: Ross Stein, Temblor.

Map showing epicenter (green dot) of magnitude-3.9 earthquake near Morgan Hill. The quake probably struck on a subsidiary of the Calaveras Fault. Credit: Ross Stein, Temblor.

Map showing epicenter (green dot) of magnitude-3.9 earthquake near Morgan Hill. The quake probably struck on a subsidiary of the Calaveras Fault. Credit: Ross Stein, Temblor.

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