March 7, 1927 Earthquake: SW, Honshu, Japan

Reference #414:

1927, March 7, at 18:30 [local time]. There was a catastrophic earthquake in Kyoto Prefecture on Tango Peninsula. This earthquake was a result of the displacement of the Tango peninsula block to the northeast and the tilting of the block. The faults, bounding the block on the

southwest and the southeast, revived. Along the first of

these, the Gomura fault, the relative horizontal displacements of the blocks were 250 cm and the vertical ones were 70 cm; along the second, Yamada fault, the vertical displacements were 470 cm and the horizontal ones were 80 cm. The length of the fresh Yamada fault which was traced on land was 7.5 km, that of the Gomura fault (which represents a series of linked smaller faults) was 18 km. However, the latter, as follows from the results of the echo sounding of coastal waters and the distribution of the focuses of the aftershocks of the earthquakes, undoubtedly continued along the sea floor for another 35 km from shore. The displacements of the flanks of the fault were apparently greater on the bottom than on land. Ships off the coast felt a strong seaquake. The passengers on a small boat at Shioe felt like they were being tossed up in the air. The Gomura fault was apparently the main fault of the earthquake, and eyewitnesses related that the Yamada fault was formed after the strong tremors had begun in this locality.

The earthquake did great damage in the epicenter zone, which is one of the centers of the silk weaving industry of the country; about 3,000 people died. It seems that Mineyama suffered especially. Here, 988 out of 998 homes completely collapsed or burned down; 1,122 people died. Sixteen fires broke out in the city in the first 10 minutes after the earthquake.

According to fishermen, at Mizu (6.5 km northeast of the Gomura fault), 2.5 hours before the earthquake, the sea level dropped 1.2-1.5 m and the bottom of the harbor was partly exposed. This situation lasted until the earthquake. At Shioe (4.5 km southwest of the fault), fishermen noted a small rise of water, about 15 cm, less than 30 minutes

before the earthquake. At Tsuiyama, according to a tide gauge record, the sea level was 4-6 cm higher than usual on the day of the earthquake, possibly, however because of a strong northeastern wind.

After the earthquake, different parts of the coast rose and fell in accordance with the general nature of the tectonic movements. West of the Gomura fault, the shore rose 80 to 20 cm on a 9 km stretch while it rose only 10-15 cm east of the fault. At Tsuiyarna, the tide gauge record

showed that the shore rose 5 cm immediately after the start of the earthquake.

The earthquake apparently caused a small tsunami, which was observed in the region of the Gomura Fault.

Table 51. 3017 dead, 3295 injured, 5 lost. 10633 homes completely destroyed, 9821 homes partly destroyed, 4961 burned down.

Iida et al. (1967): 7.III; 9h27m; 35.6 N., 135.1 E.; 10 km; M=7.5, m=0.4.

Richter (1963): 35.75 N., 134.75 E.

Reference #150:

2,925 deaths and 21,690 houses destroyed.

Reference #1068:

March 7, 1927, 36 N, 135.5 E, Tango, Japan, 3,017 deaths, 16,025 houses destroyed.

Reference #1250:

March 27, 1927 [should be March 7], 2925 deaths, $40 million, Tango, Japan.