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Home » Articles » Geology - the Cambrian PeriodGeology - the Cambrian Period
Rocks and fossils dating from the Cambrian Period.
Rocks and fossils dating from the Cambrian Period.
The base of the Cambrian Period marks the beginning of the first great explosion of animals with hard shells. Most of the animal phyla we know today had their origins at this time although many would have been represented by very unfamiliar forms. Wales has large deposits of Cambrian rocks, laid down as sediments on the floor of a deep ocean. Many of these muds and silts were later altered by intense pressures, and turned into the slates which have been quarried for centuries in north Wales. The term 'Cambrian' was first proposed by Adam Sedgwick in 1835, for the sequence of shales and sandstones he described from the Harlech Dome.
