Lashly Formation

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Lashly Formation
Stratigraphic range: Carnian
~235–222  Ma
Type Geological formation
Lithology
Primary Sandstone, mudstone
Other Conglomerate, siltstone
Location
Coordinates 77°12′S160°06′E / 77.2°S 160.1°E / -77.2; 160.1
Approximate paleocoordinates 66°42′S86°36′E / 66.7°S 86.6°E / -66.7; 86.6
Region Victoria Land
Country Antarctica
Antarctica relief location map.jpg
Pink ff0080 pog.svg
Lashly Formation (Antarctica)

The Lashly Formation is a Late Triassic (Carnian) geologic formation in Victoria Land of Antarctica. The formation has provided fossil flora and indeterminate reptiles and dicynodonts.

Contents

Tuff found in combination with Dicroidium fragments were interpreted as the result of a forest fire during the Triassic. [1]

Description

The Lashly Formation comprises carbonaceous mudstones and conglomeratic sandstones deposited in channels and on floodplains of a meandering fluvial environment.

Lashly member C consists of fining-upward cycles of medium- to fine-grained sandstone grading upward into carbonaceous siltstone and mudstone, and thin coal beds. Quartz pebbles and cobbles and mudstone clasts occur near the base of major sandstone units. Irregular lenses of coal occur along bedding planes and over large scours. Dicroidium fronds and other plant fragments are common in carbonaceous beds. [2]

Fossil content

The following fossils have been reported from the formation: [2] [3]

See also

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References

  1. Kumar et al., 2011, p.33
  2. 1 2 Lashly Formation at Fossilworks.org
  3. Hammer et al., 2004

Bibliography