Calcretes related to phreatophytic vegetation from the Middle Triassic Otter Sandstone of South West England
- 14 June 1991
- journal article
- Published by Wiley in Sedimentology
- Vol. 38 (3) , 539-551
- https://doi.org/10.1111/j.1365-3091.1991.tb00366.x
Abstract
Carbonate cementation in the Triassic Otter Sandstone of Budleigh Salterton, SW England, occurs in two distinct forms: large, vertical, concentrically zoned cyclinders, and thin subhorizontal sheets. The former represent rhizocretions of the tap roots of phreatophytic plants which colonized bars and abandoned channels on a large braidplain. The sheets represent cementation around ancient water‐tables. The precipitation of the rhizocretions took place, at least in part, during the life of the plants and δ13C and δ18O values support the view that evapo‐transpiration induced carbonate precipitation. Palaeosol profiles are rare in the Otter Sandstone, reflecting the geomorphological instability of the braidplain surfaces. In contrast, rhizocretionary and sheet calcretes, which formed several metres below the active depositional surface, are abundant because they had a high preservation potential.Keywords
This publication has 29 references indexed in Scilit:
- Braidplain and alluvial-fan environmental history and climatological evolution controlling origin and destruction of aeolian dune fields and governing overprinting of sand seas and river plains by calcrete pedogenesis in the Permian and Triassic of South Devon (England)Published by Springer Nature ,2005
- Braidplain, floodplain and playa lake, alluvial-fan, aeolian and palaeosol facies composing a diversified lithogenetical sequence in the permian and triassic of South Devon (England)Published by Springer Nature ,2005
- Calcrete palaeosols from the lower carboniferous llanelly formation, South WalesPublished by Elsevier ,2003
- Near‐surface shrinkage and carbonate replacement processes, Arran Cornstone Formation, ScotlandSedimentology, 1989
- Origins of some Early Carboniferous calcrete fabrics revealed by cathodoluminescence: implications for interpreting the sites of calcrete formationSedimentary Geology, 1989
- Relationship Between Climate and Vegetation and the Stable Carbon Isotope Chemistry of Soils in the Eastern Mojave Desert, NevadaQuaternary Research, 1988
- Stable isotope abundances in calcretesGeological Society, London, Special Publications, 1983
- Concentration of uranium and vanadium in calcretes and gypcretesGeological Society, London, Special Publications, 1983
- Genesis of Calcrete in Quaternary Soil Profiles, Hutt and Leeman Lagoons, Western AustraliaJournal of Sedimentary Research, 1982
- The Marginal Triassic deposits of South Wales: Continental facies and palaeogeographyGeological Journal, 1977