Scientists from Hiroshima University analyzing satellite data noticed elevation discrepancies pre- and post-quake along an area running roughly from Lake Ezu passing by Prefectural Hall then through Oe Machi to Shirakwa (a map is at the link). From this, the existence of two previously unknown faults was surmised.
Later on-site inspection revealed evidence of cracking in asphalt and concrete. Also, a low escarpment between the supposed faults indicates past tectonic activity. One scientist noted that the drying of the pond at Suizenji Park may be related to these faults.
On a personal note, several editors on this page might be moderately alarmed at this news as the faults seem to run quite close to Gakuen University. - William
