Talk:Lower Lias

There seems to be some confusion in this and related geology articles. The Jurassic is divided into 3: Upper, Middle and Lower. The Lower Jurassic is referred to (everywhere, apparently) as the Lias. The Lias is divided into 3: Upper, middle and lower. The lower corresponds more or less to the Hettangian and Sinemurian stages. The lower part of the Lower Lias (the Hettangian) is the Blue Lias. On searching through the other European Wikipedias, the term Lias is used everywhere, at least as an alias for the Lower Jurassic, but the term "Blue Lias" is not used. This is unsurprising, since it represents quite a localized facies. The term "Blue Lias" therefore appears to be uniquely British. The term applies not specifically to the limestone, but to the series of limestones and shales. It's the shale that's blue. Wells "Outline of Historical Geology" says "rather less than half of the Lower Lias consists of rapid alternations of bluish clay or shale with pale grey argillaceous limestone. . . this portion of the Lias is called the Blue Lias". It's a pity that there is no separate article for "Lias", which would be a suitable place for such things as derivation of the name, lists of subdivisions using the name, and linking to "Lower Jurassic" for serious geology. LinguisticDemographer 12:28, 3 March 2007 (UTC)

Could you make the necessary changes? --MichaelMaggs 19:25, 10 March 2007 (UTC)