2024-03-28T11:39:44Z
https://nagoya.repo.nii.ac.jp/oai
oai:nagoya.repo.nii.ac.jp:00001811
2023-01-16T03:47:00Z
367:368:369:370
<Original Article>Subsurface structure of the Yoro fault and its environs in central Japan as inferred from gravity anomaly
<原著論文>重力異常からみた養老断層近傍の地下構造
萩田, 直子
4223
HAGITA, Naoko
4224
足立, 守
4225
ADACHI, Mamoru
4226
志知, 龍一
4227
SHICHI, Ryuichi
4228
2001-03-21
We have newly obtained 2,655 gravity data from a dense gravity survey in an area around the Yoro Mountains, central Japan (Lat. 34°50', Long. 136°25'-136°55'). A new Bouguer anomaly map, drawn from a total of 4,028 gravity data including our new 2,655 data, shows a steep gravity gradient zone of about 10 mgal/km along the eastern slope of the Yoro Mountains. This is one of the steepest gravity gradient zones in the Japanese Islands. The steep gravity gradient zone corresponds to the Yoro fault that forms a clear lineament as the boundary line between the Yoro Mountains and the Nobi Plain. The steep gravity gradient zone does not form a straight line but slightly turns in the middle of the Yoro Mountains. A number of minor faults are observed around the turning point of the steep gravity gradient. We made Bouguer anomaly profiles along the three cross-sections across the Yoro Mountains on the north, middle (the turning point of the steep gravity gradient) and south of them. We inferred the subsurface structure of the Yoro fault by applying the two-dimensional Talwani's method to the profiles. As a result, we estimated the depth of the Yoro fault to be about 2,000 m and the gradient of the fault plane to be over 60°. Comparing the inferred subsurface structures and the geological and topographical features around the Yoro Mountains, we have concluded that the Yoro fault is not one continuous straight fault, but is composed of two faults arranges en echelon.
国立情報学研究所で電子化したコンテンツを使用している。
departmental bulletin paper
名古屋大学博物館
2001-03-21
名古屋大学博物館報告
16
43
89
http://hdl.handle.net/2237/3227
13468286
jpn