N. H. Woodcock, 2011. "Terranes in the British and Irish Cambrian", A Revised Correlation of the Cambrian Rocks in the British Isles, A. W. A. Rushton, P. M. Brück, S. G. Molyneux, M. Williams, N. H. Woodcock
Download citation file:
A complicating factor in correlating Cambrian sections in Britain and Ireland is that host terranes now geographically close to one another may have been widely separated in Cambrian time. This section reviews a terrane map of Britain and Ireland (Fig. 5) and its implications for Cambrian correlation. There are intrinsic limitations in palaeomagnetic restoration of terranes to their geographic positions in Cambrian times. Additional evidence is available from faunal distributions, tectonic reconstructions, and isotopic characterization of sediment source areas. Using these methods, some constraints can be put on the Cambrian positions of terranes relative to each other and to the major continents from which they were detached in post-Cambrian time. Some Neoproterozoic relationships are also discussed, because of doubts in some terranes as to whether late Neoproterozoic successions range up into the Cambrian.
Figures & Tables
A Revised Correlation of the Cambrian Rocks in the British Isles
This work reviews the correlation of the British and Irish Cambrian with the current (though incomplete) international standard for the Cambrian. Since the earlier edition of 1972, the basal and upper limits of the Cambrian system has been internationally agreed; so this account excludes Tremadocian rocks but includes some that were formerly considered Neoproerozoic. Half of the series and stage subdivisions are internationally agreed, but for the undefined divisions of the Cambrian the standard used here makes use of data from Avalonian successions.
Since the first edition was published, almost every aspect of the Cambrian I the British Isles has been subjected to new study. Here, the plate tectonic make-up of the British Isles is reviewed, new radiometric ages and isotopic studies are summarized and the biostratigraphy is enhanced by the study of acritarchs, especially in the Irish successions