graptolites उदाहरण वाक्य

The rock section, dominated by shale, is unusually fossiliferous, including fossilized remains of graptolites, conodonts, and trilobites.
There is an abundance of fossils of Ammonites, Trilobites, Brachiopods, Graptolites and Cloudinids in certain points of the range.
Other important groups that provide index fossils are the corals, graptolites, brachiopods, trilobites, and echinoids ( sea urchins ).
The graptolites were preserved in the Ordovician deposits of western Texas, especially some of the stratigraphic units of the Trans-Pecos region.
The dead planktonic graptolites, having sunk to the sea-floor, would eventually become entombed in the sediment and are thus well preserved.

He described also the graptolites of the local Silurian strata; and the flora of the coal-formation of the Altay Mountains and of Nebraska.
For example, if a bed containing graptolites overlies crystalline basement at some point, dating the crystalline basement will give a maximum age of that fossil assemblage.
In early 1960s she would go on field trips to Balbriggan and Skerries in north Dublin to collect Silurian graptolites, which are fossils of colonial marine animals.
State ( 1847 to 1894 ), based on his years of collecting trilobites, graptolites, brachiopods, crinoids, echinoids, mollusks and other ancient marine invertebrates.
In recognition of her having made the first discovery of graptolites in the northern Greywacke zone, her former fellow student, Ida Peltzmann, named two species for her.