Encyclopedia of Geobiology

2011 Edition
| Editors: Joachim Reitner, Volker Thiel

Molar-tooth Structure

  • Brian R. Pratt
Reference work entry
DOI: https://doi.org/10.1007/978-1-4020-9212-1_150

Definition

Molar-tooth structure is a synsedimentary, combined deformation and early diagenetic feature occurring in calcareous strata of mainly Precambrian age. It consists of arrays of closely spaced, sharply defined, upright veins , and subordinate horizontal sheets and spheroids composed of calcite microspar . Veins are vertically to obliquely oriented, discontinuous, typically strongly squashed or crumpled, and often brecciated.

Geological age

Molar-tooth structure (MTS) was first named in 1885 from its appearance on limestone bedding planes in the Mesoproterozoic Purcell Supergroup (= Belt Supergroup in USA.) along the border between southwestern Canada and adjacent northwestern Montana. Almost all occurrences are in Mesoproterozoic to late Neoproterozoic (Ediacaran) strata, representing a 1 billion-year time span from about 1,600 to 600 Ma, but there are several examples noted from the Paleoproterozoic and one from the Neoarchean (James et al., 1998; Pratt, 1998b; Shields, 2002;...

Keywords

Lime Mudstone Shear Vein Infaunal Invertebrate Sheet Crack Cement Overgrowth 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Bibliography

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Brian R. Pratt
    • 1
  1. 1.Department of Geological SciencesUniversity of SaskatchewanSaskatoonCanada