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Bonahaven Formation

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Journal Article
Published: 01 September 1977
Geological Magazine (1977) 114 (5): 355–364.
Series: Geological Society, London, Memoirs, Geological Society, London, Memoirs
Published: 01 January 2011
DOI: 10.1144/M36.62
EISBN: 9781862394117
... (Lossit) and Bonahaven formations. These strata are exposed in the metamorphic Caledonides of Scotland, although excellent preservation of sedimentary structures can be found at several sites. An extensional setting for this succession has been proposed based on stratigraphic and structural arguments...
FIGURES
Journal Article
Published: 01 September 2000
Journal of the Geological Society (2000) 157 (5): 909–914.
...M. D. BRASIER; G. SHIELDS Abstract The δ 13 C of preglacial carbonates beneath the glaciogenic Port Askaig Formation falls from +5‰ to negative values, while least-altered 87 Sr/ 86 Sr values are close to 0.7067. Postglacial ‘cap carbonates’ of the Bonahaven Formation begin with negative δ 13 C...
FIGURES
Journal Article
Published: 01 June 1980
Journal of Sedimentary Research (1980) 50 (2): 423–446.
...I. J. Fairchild Abstract Member 3 of the Dalradian Bonahaven Formation of Islay comprises mixed dolomitic-siliciclastic sediments assignable to three facies, all deposited under very shallow marine conditions. The layered facies consists of a centimeter-scale alternation of dolomitic, fine...
Journal Article
Published: 01 February 1998
Journal of the Geological Society (1998) 155 (1): 5–12.
...M. D. BRASIER; D. McILROY Abstract A chain of pellets (Neonereites uniserialis) , usually attributed to a coelomate or pseudocoelomate metazoan, is described from the middle Dalradian Bonahaven Formation of western Scotland, in sandstones not far above the Port Askaig Tillite. This trail lies more...
Journal Article
Published: 01 February 1985
Journal of the Geological Society (1985) 142 (1): 167–185.
...I. J. Fairchild Abstract The Bonahaven Formation of northern Islay, Scotland, despite having undergone high-pressure greenschist facies metamorphism, contains many relics of its diagenetic history. Early diagenetic dolomite textures, calcite and clay mineral cements are well preserved locally...
Journal Article
Published: 15 May 2017
Journal of the Geological Society (2017) 174 (5): 850–854.
... sulphate levels owing to a continental ice cover, which inhibited weathering. Sulphur isotope compositions evolve from lightest values (down to −3.1‰) at the base of the formation to highly positive compositions in the overlying Bonahaven Dolomite (mean +44.8‰). This trend is consistent with progressive...
FIGURES
Journal Article
Journal: Geology
Published: 01 November 2006
Geology (2006) 34 (11): 909–912.
... that such downturns may occur in both pre-Sturtian and pre-Marinoan strata. In addition, the Bonahaven Dolomite is not a cap carbonate to the Port Askaig Formation, but exhibits a δ 13 C rise to 12‰, which we correlate with the inferred global Keele peak. These data further document the utility of Neoproterozoic...
FIGURES | View All (5)
Image
Isotopic compositions of pyrite in Port Askaig <b>Formation</b> diamictite. Compos...
Published: 15 May 2017
Fig 3. Isotopic compositions of pyrite in Port Askaig Formation diamictite. Compositions for Port Askaig Formation and overlying Bonahaven Dolomite and Ardrishaig Phyllite plot where expected on best-fit curve for Neoproterozoic pyrite ( Halverson et al. 2010 ) fitted to Dalradian Supergroup
Journal Article
Published: 01 May 2017
Journal of Paleontology (2017) 91 (3): 393–406.
... of the Neoproterozoic Urucum Formation (Jacadigo Group) of west-central Brazil, having an age constrained between 889±44 Ma (K-Ar; basement rocks) and 587±7 Ma ( 40 Ar/ 39 Ar age of early metamorphic cryptomelane in overlying manganese ore). Early isopachous carbonate cement entombed these VSMs, preserving rare direct...
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Journal Article
Journal: PALAIOS
Published: 01 July 2016
PALAIOS (2016) 31 (7): 327–338.
... A.H. 2013 , Microstructures in metasedimentary rocks from the Neoproterozoic Bonahaven Formation, Scotland: microconcretions, impact spherules, or microfossils? : Precambrian Research , v. 233 , p. 59 – 72 , doi: 10.1016/j.precamres...
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Series: Geological Society, London, Memoirs, Geological Society, London, Memoirs
Published: 01 January 2011
DOI: 10.1144/M36.29
EISBN: 9781862394117
... Abstract The Tsagaan Oloom Formation (Fm.) in southwestern Mongolia contains two Neoproterozoic glacial deposits, with diamictite in the Maikhan Ul Member (Mb.) and in the Khongoryn Mb., which are separated by over 500 m of limestone. The Maikhan Ul Mb. ranges in thickness between 5 m...
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Journal Article
Published: 01 September 2000
Journal of Paleontology (2000) 74 (5): 767–788.
...SHUHAI XIAO; ANDREW H. KNOLL Abstract Phosphorites of the uppermost Neoproterozoic Doushantuo Formation (ca. 570 ± 20 Ma) exposed at Weng'an, South China, contain globular microfossils characterized by distinctively sculpted outer coverings and precise patterns of cell division. Forms assigned...
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Journal Article
Published: 01 July 2019
Journal of Paleontology (2019) 93 (4): 612–627.
... Bonahaven Formation, Scotland: Microconcretions, impact spherules, or microfossils? : Precambrian Research , v. 233 , p. 59 – 72 . Angerer , T. , Hagemann , S.G. , Walde , D. , Halverson , G.P. , and Boyce , A.J. , 2016 , Multiple metal sources in the glaciomarine facies...
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Journal Article
Published: 01 March 2011
Journal of the Geological Society (2011) 168 (2): 289–308.
... for loess deposition of the Nuccaleena Formation of South Australia from granulometry (angular, randomly oriented, silt, modal diameter 7ϕ) and sedimentary structures (climbing-translatent cross-stratification, linear dunes). In addition, a variety of palaeosols in the Nuccaleena Formation have red clayey...
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Journal Article
Published: 01 September 2009
Journal of the Geological Society (2009) 166 (5): 845–857.
... carbonate trends persist. The oldest carbonate rocks in the Argyll Group occur in the upper part of the Bonahaven Dolomite Formation, a mixed siliciclastic and carbonate unit. These carbonate rocks are some of the best studied in the Dalradian because they contain well-preserved sedimentary features...
FIGURES
Image
Geographic distribution of reported Neoproterozoic vasiform microfossils. R...
Published: 01 May 2017
Figure 2 Geographic distribution of reported Neoproterozoic vasiform microfossils. References: Backlundtoppen Group—Svalbard (Knoll and Calder, 1983 ); Simla Slates—India (Nautiyal, 1978 ); Bonahaven Formation—Scotland (Anderson et al., 2013 ); Callison Lake Dolostone– Canada
Journal Article
Published: 01 April 1974
Journal of the Geological Society (1974) 130 (2): 163–177.
... that the eventual source area must have comprised an appreciable area beyond the Caledonian geosyncline. The presence of the well developed limestone and stromatolites in the underlying Islay limestone and dolomites within the Port Askaig Formation itself and the overlying Bonahaven Formation (Spencer & Spencer...
Series: Geological Society
Published: 01 January 2017
DOI: 10.1144/SP448.15
EISBN: 9781786202932
... & Taylor (1977) ; this paper Bonahaven Fm, Mb 3 Neoproterozoic P: spindles; incomplete polygons V: ptygmatic Dolostone, silty dolomite Sand ✓ ✗ Shallow subtidal Fairchild (1980) Bonahaven Fm, UK Neoproterozoic P: curving, quasi-polygonal V: V-shaped, branching, with flaring...
Journal Article
Published: 01 September 1997
Journal of the Geological Society (1997) 154 (5): 917–919.
... between the lower and upper tillites is absent here, as it is in other parts of the British Isles. On Islay, the Port Askaig Tillite is separated from the overlying Bonahaven Dolomitic Formation (Fig. 1a) by c. 100 m of shallow-marine or intertidal sediments (Lower Fine-grained Quartzite Formation: Klein...