| 词条 | Clackmannan Group |
| 释义 |
| name = Clackmannan Group | image = | caption = | type = Group | age = Carboniferous | period = Carboniferous | prilithology = sandstones, mudstones | otherlithology = limestones, siltstones, ironstones, coal, seatrocks, fireclay | namedfor = Clackmannan (town) | namedby = | region = Central Lowlands of Scotland | country = United Kingdom | coordinates = | unitof = | subunits = Lower Limestone Formation, Limestone Coal Formation, Upper Limestone Formation, Passage Formation | underlies = Coal Measures Group | overlies = Strathclyde Group | thickness = | extent = | area = | map = | map_caption = }} The Clackmannan Group is the name given to a suite of rocks of late Dinantian and Namurian age laid down during the Carboniferous period in the Midland Valley of Scotland.[1] DescriptionThe Group comprises a lower unit of coarse sandstones, siltstones, mudstone, and limestones with thin coals and ironstones known as the Lower Limestone Formation, an overlying sequence of similar rocks known as the Limestone Coal Formation, then an Upper Limestone Formation and at its top the sandstones of the Passage Formation. This last formation also includes fireclays, siltstones, mudstones, ironstones, coal and seatrocks. The Clackmannan Group conformably overlays the rocks of the Strathclyde Group and underlays the Coal Measures, this latter boundary also being conformable. [2][3] PaleontologyRemains of the prehistoric shark †Cladodus elegans Newberry & Worthen, 1870 (braincase and a tooth) have been found in the Lower Limestone Formation.[4] See also{{portal|Geology|Carboniferous|Prehistory of Europe}}
References1. ^{{cite web|url=http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=CKN |title=Clackmannan Group |work=The BGS Lexicon of Named Rock Units |publisher=British Geological Society|accessdate=27 February 2014}} 2. ^British Geological Survey Research Report RR/07/01: Lithostratigraphical framework for Carboniferous successions of Great Britain (Onshore) Waters, C.N. et al 2007 3. ^British Geological Survey 1:50,0000 scale geological map sheet (Scotland) 23W Hamilton 4. ^The Braincase and Jaws of Cladodus from the Lower Carboniferous of Scotland. Michal Ginter and John G. Maisey, Palaeontology, March 2007, Volume 50, Issue 2, pages 305–322, {{doi|10.1111/j.1475-4983.2006.00633.x}} 6 : Geological groups|Geologic formations of the United Kingdom|Fossiliferous stratigraphic units of the United Kingdom|Carboniferous System of Europe|Carboniferous Scotland|Carboniferous southern paleotropical deposits |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。