Katsuta Plateau - Katsuta

…The Shimosa Plateau is also an alluvial plateau that originated from a coastal plain formed by the uplift of a shallow seabed, and together they are called the Joso Plateau. The difference between the Shimosa Plateau and the Joso Plateau is that it is divided into several plateau masses, such as the Katsuta Plateau and Namegata Plateau, by rivers such as the Kuji River, Naka River, Numa River, and Sakura River, which originate in the mountains and flow eastward or southeastward. The bottom of the dissected valley that cuts the plateau was once a sea bay due to the marine transgression during the Alluvial Epoch, but the mouth of the valley was dammed by river sediments, and it changed into the freshwater lakes of Lake Kasumigaura, Lake Kitaura, and Lake Hinuma. …

*Some of the terms mentioned in relation to the Katsuta Plateau are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…下総台地とは成因も同じく，浅海底が隆起して生じた海岸平野に由来する洪積台地で，合わせて常総台地とよばれる。下総台地と異なる点は，山地に発し東流または南東流する河川の久慈川，那珂川，沼川，桜川などに貫流されて勝田台地，行方（なめがた）台地などのいくつかの台地塊に分かれることである。また台地を刻む開析谷底は沖積世の海進によって一時海湾となっていたが，谷口を河川堆積物によってせき止められたため淡水湖の霞ヶ浦，北浦，涸（ひ）沼へと変化した。…

※「勝田台地」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