noun
Median Tectonic Line
A major geological fault line in Japan, often abbreviated as MTL. Used in academic and news contexts.
中央構造線は、西南日本を縦断する大断層です。
The Median Tectonic Line is a major fault that runs longitudinally through southwestern Japan.
From 中央 (central) + 構造 (structure) + 線 (line), a direct translation of the English geological term 'Median Tectonic Line'.