Lias

views updated May 08 2018

Lias
1. The earliest of the Jurassic epochs, followed by the Dogger. The Lias is dated at 208–178 Ma ( Harland et al., 1989), and comprises the Hettangian, Sinemurian, Pliensbachian, and Toarcian Ages.

2. The corresponding European series, roughly contemporaneous with most of the Herangi (New Zealand). Blue-grey shales and muddy limestones are typical of the Lias, with Dactylioceras and Gryphaea among the more important fossils found in the extensive outcrops of England and France.

A Dictionary of Earth Sciences AILSA ALLABY and MICHAEL ALLABY

Lias

views updated May 21 2018

Lias A commonly used term for the lowest stage of the Jurassic. The Liassic is synonymous with the Hettangian/Sinemurian Stages of Europe. Blue-grey shales and muddy limestones are typical of the Lias, with extensive outcrops in England and France.

A Dictionary of Plant Sciences MICHAEL ALLABY

Lias

views updated Jun 27 2018

Lias A name commonly given to the lowest stage of the Jurassic, with extensive outcrops of blue-grey shales and muddy limestones in Britain and France in which many fossils have been found.

A Dictionary of Zoology MICHAEL ALLABY