Tectonic activity around the Fukul plane and its evaluation

1948年的福井地震对福井平原周围的城镇和乡村造成了严重的破坏。此外，该地区还推测有许多活动断裂。然而，对这些断裂的详细调查几乎没有进行过。然后，为了弄清这些断裂的平均晚期滑动、这些断裂的古地震活动和该地区的构造活动，我们重新考察了该地区的主要断裂。本研究调查的活动断裂有Echizen海岸的断裂群、Sabae断裂、Kiotoshi断裂以及福井平原及其周围的断裂群。关于Echizen海岸的断裂群，最近一次的断裂事件发生在17世纪，当时沿海隆起3~7米。竹府盆地冲积面上形成了几米的水平差。断层还形成了向东倾斜的萨柏高地。小野盆地的吉约托希断裂长度只有3公里，平均每千年滑动高达1.7至2.3米。在福井平面上，基底逐渐向西加深，尽管有时被断层迅速加深几十米，而且不仅东侧，而且平面的西侧都与活动断裂接壤。如上所述，显然，该地区存在的活动断裂比以往推测的要多，有必要继续进行这一研究，以澄清福井县纽加塔-神户构造线的构造活动。

The 1948 Fukui earthquake did serious damage to the cities, towns and villages around the Fukui plain.In addition, many active faults are presumed in this area.However, detailed investigations are not almost conducted about these faults.Then, to make clear the average slip late, paleoseismic activity of these faults, and tectonic activity in this area, we reexamined about the major faults of this are.The active faults investigated in this study are the fault group along the Echizen coast, the Sabae fault, the Kiotoshi fault, and the fault group in and around the Fukui plain.About the fault group along the Echizen coast, the most recent fault event was the 17th century, and the coastal area was upheaved 3 to 7meters at that time.The Sabae fault formed the level difference of several meters on alluvial surface in Takefu basin.The fault also formed the Sabae upland which is tilted eastward.The Kiotoshi fault in the Ono basin, the length of this fault is as short as 3 kirometers, shows the high average sliplate as 1.7 to 2.3 meters per 1,000 years.In the Fukui plane, the basement is gets deep toward the west gradually, though sometimes deep rapidly by faults several tens of meters, and not only the eastern side but also the western side of the plane is bordered with active faults.As shown above, it has become clear that many active faults exit in this area more than it is presumed previously.It is necessary to continue this study further to clarified the tectonic activity along the Nugata-Kobe tectonic line in Fukui prefecture.