Stratigraphy, mineralogy and tectonic setting of Silurian K-bentonites in southern England and Wales
| Autor: | Huff, W.D., Morgan, D.J. |
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| Jazyk: | angličtina |
| Rok vydání: | 1990 |
| Zdroj: | Périodiques Scientifiques en Édition Électronique. |
| Popis: | Silurian K-bentonite beds occur throughout much of the Llandovery, Wenlock, and Ludlow of southern England and Wales. Outcrop and borehole samples can be correlated with precision at Series level, and in some cases, at Stage level using chemical fingerprinting techniques. Multivariate statistical analysis of trace element data reflecting original magma composition shows slight but persistent and recognizable differences between groups of K-bentonites. Most K-bentonites consist of RO to R3 ordered illite/smectite with accessory kaolinite in Llandovery and Wenlock samples. K-bentonites that have been reworked following deposition contain detrital chlorite and illite. Magmatic discrimination diagrams show REE and immobile elements are characteristic of plate-margin calcalkaline volcanoes associated with subduction zone settings. The source volcanoes were located in an active geotectonic collision zone associated with the late-stage closing of Iapetus. Huff W.D., Morgan D.J. Stratigraphy, mineralogy and tectonic setting of Silurian K-bentonites in southern England and Wales. In: Proceedings of the 9th international Clay Conference, Strasbourg, 1989. Vol IV : Clays in sediments. Diagenesis and hydrothermalism. Strasbourg : Institut de Géologie – Université Louis-Pasteur, 1990. pp. 33-42. (Sciences Géologiques. Mémoire, 88) |
| Databáze: | OpenAIRE |
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