Difference between radioactive dating radiometric dating
This is the principle of original horizontality: layers of strata are deposited horizontally or nearly horizontally (Figure 2).
Thus, any deformations of strata (Figures 2 and 3) must have occurred after the rock was deposited.
Third, magnetism in rocks can be used to estimate the age of a fossil site.
This method uses the orientation of the Earth's magnetic field, which has changed through time, to determine ages for fossils and rocks.
To compare bond polarities, compare the difference in the electronegativities between the atoms.
The difference between carbon (with an electronegativity of 2.55) and sulfur…
Layers that cut across other layers are younger than the layers they cut through (principle of cross-cutting relationships).
Younger layers are deposited on top of older layers (principle of superposition).
The age of the fossil must be determined so it can be compared to other fossil species from the same time period.
Understanding the ages of related fossil species helps scientists piece together the evolutionary history of a group of organisms.
For example, based on the primate fossil record, scientists know that living primates evolved from fossil primates and that this evolutionary history took tens of millions of years.
By comparing fossils of different primate species, scientists can examine how features changed and how primates evolved through time.