Hi,
Scientists have used rock samples to date the Earth's past. They also might use Steno's principles.
Relative dating is the determination of the age of a rock or geological event by comparing with other rock/ geologic events. Absolute dating is a form of geologic dating that gives an actual date or age in history that the item was formed or died in years.
Steno's principles are:
Law of superposition - Bottom layer is the oldest, top layer of the youngest In undisturbed layers of sedimentary rock or magma.
Original horizontally - When sedimentary rock layers form, they are "created in a horizontal form.
The Principle of Lateral Continuity -<span> States that layers of sediment initially extend </span>laterally<span> in all directions.
Faith xoxo
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Divergent boundaries move oceanic plates (plates found in the ocean) away from each other, making magma seep in to fill those cracks, thus spreading the sea floor.
A biome is defined as the large ecological area where the formation of plants and animals with common characteristics gather due to the similar climates. If I were an ecologist, and i will be determining whether an entire river and lake biome is being threatened by human activity, the indicator species that i might look for are the ones that have been introduced into the biome.
