Conjugate fault system of strike-slip type with some vertical component was associated with the 1927 Earthquake (Table 1; Fig.1) in Tango Peninsula, Central Japan. Detailed field observations have been described in many reports and papers which were published by lots of researchers and organizations. Those data are here compiled as a list (Table 3) with detailed location maps (Figs.8 ABCD, Fig.9).
Based on the data compiled, distribution of major surface faults and a m ount of displacement on the fault traces are shown in Figs.7AB and Table 2. The followings are summarized by descriptions and reviews of surface faults and fault topographies.
1) The Go m ura fault zone is composed of en echelon arranged several faults, generally trending with the direction of N30°W. The total length having clear fault morphology is 14km on land, and the morphology become obscure to the southeastern part.
2) The seismic faults had ap p eared on the pre-existed Quaternary faults. The features of the morphology are not so obvious, as these faults belong to the active faults of lower class B or class C in term of the average slip rate.
3) Each fault within the Gomura fault zone has the maximum value at the central part on the distribution for the amount of displacement at the 1927 earthquake, which decrease to the both ends.
4) Each fault is arranged with en echelon, and these make the Gomura fault zone with altogether. The distribution of displacement, especially of left slip, shows the wavy pattern.
5) Nevertheless, the maximum value of the left slip in the G o mura fault zone is recognized around Go, Amino Town.
6) Based on the relationship between the southeastward length and the distribution of amount of displacement is known, the northwestward extension to the Japan sea bottom is estimated as about 4km or slightly longer. If the subordinary faults such as the Kuchi-Ono and Mie faults are included in this zone, the length become much longer.
7) The G o mura fault zone was a very clear seismic fault, and was associated with large amount of displacement throughout the whole zone. Especially, cumulative fault topography is distinctive along the Gomura (Takahashi) fault. The offset features of stream valley and ridge of about 100m in maximum are seen along this strand. These features are explained by the repetition of the displacement in 1927 event in the late Quaternary period (about half Million of years).
8) The recurrence interv a l of the Gomura fault zone is longer than several thousands of years, possibly about 10,000 years.
9) Althou g h the Yamada fault zone, being another conjugate fault, has much clearer geomorphic and geologic features of offset than the Gomura fault zone, the amount of displacement in 1927 event was small and the length of the surface rupture was short.
10) The 1927 earthquake trigger e d small dislocations localy along the main part of the pre-existed Yamada fault zone (cf. Fig.7B). Therefore, the Yamada fault zone may dislocate in the time of the other large earthquakes in figure.
