Japanese to English: 佐田岬半島の地質 Geology of the Sadamisaki Peninsula General field: Social Sciences Detailed field: Geology | |
Source text - Japanese 地質
佐田岬半島の北側の沖合には、関東から九州にかけて西南日本を南北に分ける大きなみぞ(断層)が東西に走っています。このみぞを中央構造線といいます。佐田岬半島は、この中央構造線に沿うように西へ向かって伸びています。
東西につらなる半島の尾根部分(分水嶺)は、地層が曲がって山になる部分(背斜)とほぼ重なっているため、例えば海の波がきても、波は地層の表面をなでるようにあたるだけで地面が削られにくく、陸地が細長いながらもよく耐えて残りやすかったと考えられています。また、西の海に向かって傾く半島の主軸部分と直交して、南北方向に割れる胴切り断層がいくつかあり、その断層のそれぞれの西側がずれてせり上がっているため、西に向かって少しずつ沈み、海に近づきそうになるはずの半島の標高を何度か引き上げて高度を保ってくれたことで、この鋭く細長い半島が形作られました。 | Translation - English Geology
Along the peninsula’s northern shore is a major fault line called the Medial Tectonic Line. It stretches from the Kantō Plain to Kyūshū, dividing southwestern Japan into north and south. The Sadamisaki Peninsula closely follows this line as it extends west.
East-west mountain ridges on the peninsula are almost overlapped with an anticline in the earth’s crust. It is thought that this is why the peninsula has borne the brunt of the waves, despite its length and narrow size. However the waves beat against the shore, they have as much effect on the land as if they were only licking its surface. Meanwhile, the waves come perpendicular to the main thrust of the peninsula leading out into the western seas. A number of fault lines, whose western edges are slightly elevated, cut north to south across the peninsula. Thanks to these natural features, instead of sinking slowly to the west, or having a very low elevation throughout, the peninsula has rather been raised several degrees and kept from sinking. That is how this sharply narrow and long peninsula was formed. |