Geologists employ biostratigraphy, the use of index fossils, for dating sedimentary rock units like the Coon Creek.
12.
Found in the late Ludlow-aged Kuanti Formation, the remains were dated using conodonts as index fossils.
13.
With Garretson's help, Grabau went on to write papers about his findings on North American index fossils.
14.
Since there are no index fossils, the sedimentary rocks cannot be dated using fossils, like they can in Phanerozoic rocks.
15.
Other important groups that provide index fossils are the corals, graptolites, brachiopods, trilobites, and echinoids ( sea urchins ).
16.
They are excellent candidates for index fossils used for dating rock formations in the Paleozoic Era and when other fossils are not available.
17.
Since their armoured plates are often preserved and are abundant in certain localities, aetosaurs serve as important Late Triassic tetrapod index fossils.
18.
It is known from abundant fossils representing sixteen species, which serve as important index fossil used to date geologic formations in China.
19.
Their fossils are scientifically significant as many are now used as index fossils or were completely unknown to science before their discovery here.
20.
The only song from " Suffer " that has never been performed live is " Part IV ( The Index Fossil ) ".
