The Zechstein Sea
An inland sea evaporates repeatedly, leaving kilometre-thick salt beds beneath northern Europe.
- When
- —
- Duration
- 5.1 million years
- Known to
- ± 2 million years
- Era
- Permian, Paleozoic
Between about 257 and 251 million years ago a shallow epicontinental sea covering what is now the North Sea, Britain, Germany and Poland floods and dries out in cycles, precipitating vast deposits of halite, gypsum and potash. The salt later flows plastically under burial, rising into domes that trap oil and gas — the structural reason the southern North Sea became a major gas province.