With this in mind geologist have long known that the deeper a sedimentary rock layer is the older it is, but how old?
Although there might be some mineral differences due to the difference in source rock, most sedimentary rock deposited year after year look very similar to one another.
Dating is a technique used in archeology to ascertain the age of artifacts, fossils and other items considered to be valuable by archeologists.
There are many methods employed by these scientists, interested in the old, to get to know the age of items.
A chance encounter between determined fishermen and a great white shark off the Tuscan coast in 1666 sparked a chain of events that would help change humans views of fossils and Earth’s geologic past (Cutler 2003, pp. Nicolas Steno (1638-1686) dissected the head of this shark and realized fossil tongue stones believed to be petrified snake or dragon tongues were actually fossil shark teeth (Prothero 1998, p. One problem still existed, how do fossils become embedded in solid rock?
Steno recognized that fossils represent organisms that became buried in sediment, which later turned into rock.
Stratigraphy is a branch of geology that studies rock strata with an emphasis on distribution, deposition, age and evidence of past life.
Nicolas Steno, William Smith, Georges Cuvier, Alexandre Brongniart, and James Hutton developed the basic rules for the science of stratigraphy.
Making this processes even more difficult is the fact that due to plate tectonics some rock layers have been uplifted into mountains and eroded while others have subsided to form basins and be buried by younger sediments.The study of fossils and the exploration of what they tell scientists about past climates and environments on Earth can be an interesting study for students of all ages.Teaching about Earth's history is a challenge for all teachers.Absolute dating, on the other hand is capable of telling the exact age of an item using carbon dating and many other techniques that were not there in earlier times.Relative dating makes use of the common sense principle that in a deposition of layers.