Y gwahaniaeth rhwng diwygiadau o "Triasig"

Lleihawyd o 2 feit ,  6 mis yn ôl
→‎top: Misoedd cyfeiriadaeth, replaced: August → Awst using AWB
B (→‎top: clean up)
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Dyma gyfnod cyntaf y [[gorgyfnod]] [[Mesosöig]] a amcangyfrifir ei fod 251-66 miliwn o flynyddoedd [[CP]]. Mae cychwyn a diwedd y Triasig yn digwydd ac yn dynodi digwyddiadau mawr sy'n ymwneud â [[difodiant]] (''extinction'').<ref name="SahneyBenton2008RecoveryFromProfoundExtinction">{{ cite journal | url=http://journals.royalsociety.org/content/qq5un1810k7605h5/fulltext.pdf |author1=Sahney, S. |author2=Benton, M.J. |lastauthoramp=yes | year=2008 | title=Recovery from the most profound mass extinction of all time | journal=Proceedings of the Royal Society: Biological | doi=10.1098/rspb.2007.1370 | volume = 275 |format=PDF | pmid=18198148 | issue=1636 | pmc=2596898 | pages=759–65}}</ref>
 
Bathwyd y term 'Triasig' yn 1834 gan [[Friedrich AugustAwst von Alberti|Friedrich von Alberti]], ar ôl y 3 haen o greigiau a geir ledled [[yr Almaen]] a gorllewin [[Ewrop]]: gwely o graig coch y ''red bed'', calchfaen forol a chyfres o garreg laid a [[tywodfaen|thywodfaen]] - sef y "Trias".<ref>Friedrich von Alberti, ''Beitrag zu einer Monographie des bunten Sandsteins, Muschelkalks und Keupers, und die Verbindung dieser Gebilde zu einer Formation'' [Contribution to a monograph on the colored sandstone, shell limestone and mudstone, and the joining of these structures into one formation] (Stuttgart and Tübingen, (Germany): J. G. Cotta, 1834). Alberti coined the term "Trias" on [https://books.google.com/books?id=1ClSAAAAcAAJ&pg=PA324#v=onepage&q&f=false page 324] :<br>"… bunter Sandstein, Muschelkalk und Keuper das Resultat einer Periode, ihre Versteinerungen, um mich der Worte E. de Beaumont’s zu bedeinen, die Thermometer einer geologischen Epoche seyen, … also die bis jezt beobachtete Trennung dieser Gebilde in 3 Formationen nicht angemessen, und es mehr dem Begriffe Formation entsprechend sey, sie zu einer Formation, welche ich vorläufig ''Trias'' nennen will, zu verbinden."<br>( … colored sandstone, shell limestone, and mudstone are the result of a period ; their fossils are, to avail myself of the words of E. de Beaumont, the thermometer of a geologic epoch ; … thus the separation of these structures into 3 formations, which has been maintained until now, isn't appropriate, and it is more consistent with the concept of "formation" to join them into one formation, which for now I will name "trias".)</ref>
 
==Gweler hefyd==
452,433

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