Definition of Dalradian in English:



  • 1Relating to or denoting a series of late Precambrian metamorphic rocks, occurring in Scotland and Ireland.

    • ‘The Dalradian rocks in Arran were initially folded during the Caledonian orogeny into a recumbent structure known as the Aberfoyle synform.’
    • ‘There is considerable uncertainty in both the age of deposition of the Dalradian sediments in the Scottish Highlands and their subsequent metamorphism.’
    • ‘Peak metamorphic temperatures in the Dalradian schists reached 620 30°C in the north but only c.400°C in the south.’
    • ‘Kennedy and McKerrow observed that the Late Precambrian / Cambrian Dalradian sequences of the Scottish Highlands were deformed in the Ordovician.’
    • ‘Thus, movement along the Mannin Thrust brought mid-crustal plutons and Dalradian country rocks tectonically above the extrusive volcanic sequence.’
    1. 1.1The Dalradian series of rocks.
      • ‘Current controversy over the maximum age of the Dalradian arises from contrasting interpretations of structural and lithostratigraphical relationships, and differing geological interpretation of chronological data.’
      • ‘Evidence for the maximum age of the Dalradian is ambiguous, and interpretations differ markedly.’
      • ‘The age signature of detrital zircons within the Dalradian as well as the Torridonian and Moine is consistent with derivation from a Laurentian hinterland.’
      • ‘Others have proposed a prolonged period of extension for Laurentia during which the Dalradian was deposited, and suggested that the Neoproterozoic events are related to extension.’
      • ‘Here, the first Grampian deformation to affect the Dalradian can be matched with very low-grade rocks in the adjacent Clew Bay Complex, a dismembered accretionary complex.’


Late 19th century: from Dalrad-, from Dalriada (by alteration), + -ian.