Zamora, Omar (2012) All about silurian period and events. University Publications, Delhi, India. ISBN 9788132337089
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Abstract
The Silurian is a geological period and system that extends from the end of the Ordovician Period, about 443.7+ 1.5 Mya (million years ago), to the beginning of the Devonian Period, about 416.0+ 2.8 Mya (ICS, 2004, chart). As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by several million years. The base of the Silurian is set at a major extinction event when 60% of marine species were wiped out. The Silurian system was first identified by British geologist Sir Roderick Impey Murchison, who was examining fossil-bearing sedimentary rock strata in south Wales in the early 1830s. He named the sequences for a Celtic tribe of Wales, the Silures, following the convention his friend Adam Sedgwick had established for the Cambrian. In 1835 the two men presented a joint paper, under the title On the Silurian and Cambrian Systems, Exhibiting the Order in which the Older Sedimentary Strata Succeeded each other in England and Wales, which was the germ of the modern geological time scale. As it was first identified, the "Silurian" series when traced farther afield quickly came to overlap Sedgwick's "Cambrian" sequence, however, provoking furious disagreements that ended the friendship. Charles Lapworth resolved the conflict by defining a new Ordovician system including the contested beds. An early alternative name for the Silurian was "Gotlandian" after the strata of the Baltic island of Gotland The French geologist Joachim Barrande, building on Murchison's work, used the term Silurian in a more comprehensive sense than was justified by subsequent knowledge. I have divided the Silurian rocks of Bohemia into eight stages. His interpretation of him was questioned artest fossils in 1854 by Edward Forbes, and the later stages of Barrande, F, G and H, have since been shown to be Devonian despite these modifications in the original groupings of the strata, it is recognized that Barrande established Bohemia as a classic ground for the study of the earliest fossils.
| Item Type: | Book |
|---|---|
| Subjects: | Q Science > QE Geology |
| Divisions: | Electronic Books |
| Depositing User: | Esam @ Hisham Muhammad |
| Date Deposited: | 12 Feb 2023 06:49 |
| Last Modified: | 12 Feb 2023 06:49 |
| URI: | http://odlsystem2.utm.my/id/eprint/3991 |
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