Enshu Plain - Enshu Heiya

...Part of the western half belongs to the Inner Zone of Southwest Japan because the Median Tectonic Line passes near the northwestern end, but most of it belongs to the Outer Zone, and the Akaishi Mountains, with their ancient rock layers arranged in a band of approximately north-south direction, occupy a large area at an altitude of 2,500 to 3,000 meters. There are many rapid rivers with abundant water volume in the western half, such as the Tenryu River, the Oi River, and the Abe River, which flow south in vertical valleys, and develop fan-shaped plains made of thick gravel layers along the coast, such as the Enshu Plain, the Oigawa Plain, and the Shizuoka Plain. The Fuji River is large in the eastern half, but its flow length within the prefecture is only 18 km, and the downstream Gakunan Plain and the North Izu Plain in the lower Kano River basin are also smaller in scale than the plains in the western half.

*Some of the terminology that refers to the "Enshu Plain" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…西半部は中央構造線が北西端近くを通るため，一部分が西南日本内帯に属するが，大部分は外帯に属し，古期岩層がほぼ南北方向の帯状に配列する標高2500～3000mの赤石山脈が広い面積を占める。河川は天竜川，大井川，安倍川など西半部に豊かな水量をもつ急流が多く，縦谷をなして南流し，海岸沿いに遠州平野，大井川平野，静岡平野など厚い砂礫（されき）層からなる扇状地性の平野を発達させる。東半部では富士川が大きいが，県内での流長は18kmにすぎず，下流の岳南平野，狩野川下流域の北伊豆平野も西半部の平野に比べると規模が小さい。…

※「遠州平野」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報