Search results
Results from the WOW.Com Content Network
South of the Brigantes, the geographer Ptolemy reported three tribes whose territories stretched from the Irish Sea to the North Sea. The Ordovices occupied the westward lands and had two noteworthy cities, Branogenium which was located 195 Roman miles from London, most likely at Leintwardine, and Mediolanum which was located 200 Roman miles from London.
The Ordovician, named after the Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same rock beds in North Wales in the Cambrian and Silurian systems, respectively. [11]
The Early Ordovician is the first epoch of the Ordovician period, corresponding to the Lower Ordovician series of the Ordovician system. It began after the Age 10 of the Furongian epoch of the Cambrian and lasted from 486.85 to 471.3 million years ago, until the Dapingian age of the Middle Ordovician .
Pages in category "Ordovician trilobites" The following 136 pages are in this category, out of 136 total. This list may not reflect recent changes. A. Agnostida;
Recent estimates (ICS and Cosuna) place the beginning of Gasconadian, and Ordovician, anywhere from about 488 to 500 million years ago, with a duration ranging from 9.7 to 10 million years respectively putting the end about 464 m.y.a. Both give estimates of over half the Early Ordovician. 60 percent according to the ICS, 2/3 according to Cosuna.
The Great Ordovician Biodiversification Event (GOBE) was an evolutionary radiation of animal life throughout [1] the Ordovician period, 40 million years after the Cambrian explosion, [2] whereby the distinctive Cambrian fauna fizzled out to be replaced with a Paleozoic fauna rich in suspension feeder and pelagic animals.
The Late Ordovician is the third and final epoch of the Ordovician period, lasting 15.1 million years and spanning from around 458.2 to 443.1 million years ago. [ 4 ] [ 5 ] The rocks associated with this epoch are referred to as the Upper Ordovician Series.
The Ordovician Period of the Paleozoic Era, in the Phanerozoic Eon.. This category contains events which happened in the Ordovician, a division of the geologic time scale.See geologic time scale for information about its divisions and how they relate to each other.