A model for the  Lower Palaeozoic evolution of the southern margin of the early Caledonides of Scotland and Ireland

Powell, Derek

doi:10.1144/sjg07040369

Cited by 25 publications

(7 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These could explain the magnetic anomalies, but appear unlikely in view of the lack of the expected positive gravity signatures (Powell, 1970(Powell, ,1971.…”

Section: Discussionmentioning

confidence: 98%

Crustal magnetization variations across the Iapetus Suture Zone

Kimbell

Stone

1995

Geol. Mag.

View full text Add to dashboard Cite

The Iapetus Suture (Solway) line coincides with a magnetic low, which lies between magnetic highs over southwestern Scotland and the Lake District-Isle of Man region. Although topography on deep magnetic basement can account for these long wavelength geophysical variations, an explanation which involves lateral basement magnetization contrasts is preferred on the basis of (a) correlations between inferred magnetization boundaries and major structures delineated from other evidence, and (b) the apparent westward continuation of the Solway low through Ireland and Newfoundland across areas with very different subsidence histories but similar position with respect to the collision of Laurentia and Avalonia. In the preferred model, relatively

show abstract

“…These could explain the magnetic anomalies, but appear unlikely in view of the lack of the expected positive gravity signatures (Powell, 1970(Powell, ,1971.…”

Section: Discussionmentioning

confidence: 98%

Crustal magnetization variations across the Iapetus Suture Zone

Kimbell

Stone

1995

Geol. Mag.

View full text Add to dashboard Cite

show abstract

“…Although this suggestion has been challenged by Powell (1971) on geophysical grounds, a recent seismic study (Bamford et al 1977) strongly suggests that a 6*48 km sec -1 layer (Lewisian basement, according to Smith and Bott 1975) extends southwards through the Midland Valley but does not continue into the Southern Uplands.…”

Section: Introductionmentioning

confidence: 99%

Pb isotopic composition of feldspars from Scottish Caledonian Granites, and the nature of the underlying crust

Blaxland

Aftalion

Breemen

1979

SJG

View full text Add to dashboard Cite

Synopsis Common Pb isotopic ratios for 11 feldspar separates from Caledonian granite intrusions (400 Ma old) show a linear alignment on a 207 Pb/ 204 Pb vs 206 Pb/ 204 Pb diagram, the best-fit regression line suggesting a lower intercept age of 2700 Ma, using conventional growth-curve models. This accords well with previously published Pb ages for the Lewisian basement in north-west Scotland ( Chapman and Moorbath, 1977 ), and strongly suggests a Lewisian Pb component in the Caledonian granites. Furthermore, the feldspars from the Southern Uplands granites are significantly more radiogenic than those from the Highlands and Midland Valley; this relationship is consistent with the presence of an older crustal layer beneath the more northerly regions which does not extend southwards into the Southern Uplands.

show abstract

“…Evidence regarding the nature of the basement in the Southern Uplands is meagre, the only other rocks (other than the Ballantrae Igneous Complex) so far known to have a pre-Llandeilo age being the Arenig shales of Raven Gill, Abington, incorporated as part of the Moffat Shales succession within the Leadhills Line (Walton and Weir 1974). Geophysical evidence (McLean and Qureshi 1966;Powell 1972) suggests that the Southern Uplands may have a metamorphic basement up to 8 km thick.…”

Section: Discussionmentioning

confidence: 99%

The stratigraphical setting of the Cairnsmore of Fleet Pluton, Galloway

Cook¹,

Weir

1980

SJG

View full text Add to dashboard Cite

Synopsis The granitic pluton of Cairnsmore of Fleet was intruded into the Moffat Shales (Caradoc-Fronian) and an overlying flysch facies. The flysch is divisible into two formations: the Craignell Formation, in the NW of the area, and the Knockeans Formation, to the SE. Within the Craignell Formation, an evolution of greywacke facies from basic through lithic to silicic is recognized, the base being diachronous from Idwian in the SE upwards to early Fronian in the NW. The Knockeans Formation, deduced to be the youngest unit, completes the evolutionary sequence of the greywackes from basic to a silicic facies, and is correlated with the Hawick Group (Telychian or later). The anomalous NW encroachment of flysch over pelagic facies may relate to a sedimentary source within a ridge located along the Iapetus oceanic suture.

show abstract

A model for the Lower Palaeozoic evolution of the southern margin of the early Caledonides of Scotland and Ireland

Cited by 25 publications

References 12 publications

Crustal magnetization variations across the Iapetus Suture Zone

Crustal magnetization variations across the Iapetus Suture Zone

Pb isotopic composition of feldspars from Scottish Caledonian Granites, and the nature of the underlying crust

The stratigraphical setting of the Cairnsmore of Fleet Pluton, Galloway

Contact Info

Product

Resources

About