This is for my science class, please help!
2007-05-15 10:11:04 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Earth Sciences & Geology
Index fossils are described as global, short-lived, and distinct. If you have a very recognizable fossil all over the world that only appears for a short time in the rock record then it is easier to apply a date and correlate that particular rock sequence around the world. So if I see fossil A in a rock in North America and the same fossil in a rock in China then it is mostly safe to assume that these rocks, now so very far apart, are the same age (even if its a different type of rock).
2007-05-15 10:16:18 · answer #1 · answered by Lady Geologist 7 · 0⤊ 0⤋
Say index fossil happens pretty between an prolonged time A and B in sedimentary rocks that we are in a position to date as a results of fact of igneous intrusions. you come across this same fossil in a distinctive little bit of rock in a locale that's perplexing to this element. you may wisely infer that the recent rock is elderly between A and B. CREO NONSENSE warning: Creos in lots of circumstances fake that using the index fossils is around reasoning. it isn't any longer, as a results of fact it consistently comes back to base strains favourite by potential of different potential.
2016-12-11 10:25:10 · answer #2 · answered by rosalee 4 · 0⤊ 0⤋
they are indications of certain animals/plants that were only living and died for one specific geologial time period and other animals/plants that lived either before and/or after could be found in layers of strata located below and/or aove that layer where the index fossil was found.
2007-05-15 12:19:13 · answer #3 · answered by ? 4 · 0⤊ 0⤋