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tonstein

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Journal Article
Published: 29 March 2021
Scottish Journal of Geology (2021) 57 (1): sjg2020-019.
...Richard A. Batchelor Abstract A volcanogenic clay bed (tonstein) has been identified in the Balcomie Beds of the Inverclyde Group near Crail, East Fife. Its chemical composition suggests an undersaturated alkaline magma source. This horizon may be contemporaneous with the early Carboniferous...
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Journal Article
Journal: Clay Minerals
Published: 20 January 2021
Clay Minerals (2020) 55 (4): 329–341.
...-marine facies containing >50% kaolinite are termed ‘tonsteins’ (Spears, 2012 ). In order to avoid inaccurate characterization, we refer to both as ‘altered ash beds (or layers)’ regardless of their depositional setting (Kiipli et al. , 2010 ). Altered ash layers frequently represent beds...
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Journal Article
Journal: PALAIOS
Published: 27 February 2018
PALAIOS (2018) 33 (2): 69–84.
... architecture that are consistent with aestivation burrows produced by lungfishes. The occurrence of this structure, in association with the features of the paleosols, indicates a seasonal climate with drought events. Additionally, a tonstein layer is interbedded in the paleosol sequence, indicating...
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Journal Article
Published: 15 May 2017
Journal of the Geological Society (2017) 174 (5): 836–849.
... the Moscovian and Kasimovian (Westphalian–Stephanian) tonsteins. The age of a Langsettian tonstein along with data provided by several papers stating that in the Cantabrian Zone Langsettian floras were contemporaneous with lowermost Moscovian fusulines suggest that Langsettian floras could have been younger...
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Journal Article
Published: 01 November 2012
Journal of the Geological Society (2012) 169 (6): 713–721.
... altered volcanic ash layers (bentonites and tonsteins) that occur interbedded with cyclic siliciclastic sedimentary rocks. The dates constrain the average periodicity of western European late Carboniferous (Arnsbergian to early Langsettian) cyclic sedimentation to between 89 and 124 ka per cycle...
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Journal Article
Published: 01 January 2012
Journal of the Geological Society (2012) 169 (1): 37–51.
... zircon ages from a bentonite deposited during the Arnsbergian (mid-Serpukhovian) regional substage and tonstein of earliest Bolsovian (early Moscovian) regional substage have been determined. The weighted mean 206 Pb/ 238 U ages of 328.34 ± 0.55 and 314.37 ± 0.53 Ma (total uncertainty), respectively...
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Journal Article
Published: 01 September 2006
Bulletin of Canadian Petroleum Geology (2006) 54 (3): 221–237.
... (<500 m), has high vitrinite content (>86 vol%), is well-cleated, shows high diffusivity [average tau (τ) value is 56 hours] and has high natural fracture permeability (>30 mD) in the minesites. The coal averages 2.2 m in thickness but has a high ash content (32 wt%). A tonstein band is present...
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Journal Article
Journal: Clay Minerals
Published: 01 March 2006
Clay Minerals (2006) 41 (1): 395–416.
.... There are also clay-rich rocks that differ from the normal mudrocks and a knowledge of the clay mineralogy of these is a necessary prerequisite to a full understanding of their origins. Mudrocks falling in this category, and described below, include bauxitic clays, flint clays, fragmental clay rocks, tonsteins...
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Journal Article
Published: 01 December 2002
Clays and Clay Minerals (2002) 50 (6): 766–770.
...Don M. Triplehorn; Bruce F. Bohor; William J. Betterton Abstract The coarse, non-clay fraction of many flint-like kaolinitic claystones often contains mineral grains diagnostic of the claystone’s origin and, in the case of tonsteins (altered volcanic ashes), may also provide minerals suitable...
FIGURES
Journal Article
Published: 01 January 2002
Rocky Mountain Geology (2002) 37 (2): 165–171.
... and tonsteins. Although tuffs and tonsteins are known to exist in Upper Cretaceous parts of the strata, ages for these are either yet to be determined or are unreliable. The few reliable ages, based on 40 Ar– 39 Ar, conventional K-Ar, and fission-track dating, fall into two groups: early Paleocene and early...
FIGURES
Journal Article
Journal: Clay Minerals
Published: 01 September 2001
Clay Minerals (2001) 36 (3): 389–402.
.... The kaolinite is thought to have formed mainly on the adjacent landmass, but some crystallization of gels within the basin is not ruled out. Tonsteins, which formed from the in situ alteration of airfall volcanic ashes, are very common in the coal measures and are up to 0.5 m thick. Finally, kaolinite deposits...
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Journal Article
Published: 01 March 1997
Bulletin de la Société Géologique de France (1997) 168 (2): 207–217.
Journal Article
Published: 01 November 1996
Bulletin de la Société Géologique de France (1996) 167 (6): 761–771.
Journal Article
Journal: GSA Bulletin
Published: 01 January 1996
GSA Bulletin (1996) 108 (1): 120–125.
Series: GSA Special Papers
Published: 01 January 1994
DOI: 10.1130/SPE294-p41
... of the Kanawha Formation (Middle Pennsylvanian); (2) extended the name “Fire Clay” into West Virginia from Kentucky for a coal bed regionally identified by its flint clay (tonstein) parting and miscorrelated in different areas of West Virginia as the older Hernshaw coal bed or the younger Chilton coal bed...
Series: GSA Special Papers
Published: 01 January 1994
DOI: 10.1130/SPE294-p87
... The Middle Pennsylvanian Fire Clay tonstein, mostly kaolinite and minor accessory minerals, is an altered and lithified volcanic ash preserved as a thin, isochronous layer associated with the Fire Clay coal bed. Seven samples of the tonstein, taken along a 300-km traverse of the central...
Series: GSA Special Papers
Published: 01 January 1994
DOI: 10.1130/SPE294-p105
... 40 Ar/ 39 Ar plateau age spectra of seven sanidine samples from the Fire Clay tonstein (Middle Pennsylvanian), collected along a 300-km traverse in the Appalachian basin, range from 310.3 to 311.4 Ma. All plateau ages agree, within the limits of analytical precision, with their respective...
Journal Article
Published: 01 December 1993
Bulletin of Canadian Petroleum Geology (1993) 41 (4): 464–469.
... and significance of kaolinite-rich, volcanic ash horizons (tonsteins) in the Ardley coal zone, Wabamun, Alberta, Canada THOMAS D. DEMCHUK Amoco Production Company Geoscience Technical Services P.O. Box 3092 Houston, TX 77253-3092 D.A. NELSON-GLATIOTIS Department of" Geology and Geophysics The University of Calgary...
Series: GSA Special Papers
Published: 01 January 1993
DOI: 10.1130/SPE285-p1
... tonsteins, and these beds have only recently been universally accepted as being volcanic in origin. The recognition of tonsteins as altered volcanic ash is based on mineralogy, texture, radiometric age, and field relations. Tonsteins occur on almost every continent, but are best known from Europe...
Journal Article
Journal: GSA Bulletin
Published: 01 November 1992
GSA Bulletin (1992) 104 (11): 1515–1527.
...PAUL C. LYONS; WILLIAM F. OUTERBRIDGE; D. M. TRIPLEHORN; HOWARD T. EVANS, JR.; ROGER D. CONGDON; MIRTHA CAPIRO; J. C. HESS; WILLIAM P. NASH Abstract The Fire Clay tonstein is a kaolinized, airfall volcanic ash bed that was deposited in a widespread late Carboniferous peat-forming mire. Eleven...