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Relative and Absolute Age

Horizontales
A method for measuring the age of a material by comparing the amount of a radioactive element within a rock or fossil to the amount of its decay product.
A type of rock formed by sedimentation of material (sand, silt & clay) at the earths surface and within bodies of water.
The length of time it takes for half of the atoms in a sample of radioactive element to decay into atoms of a stable element.
The observation that groups of plants and animals follow each other in time in a predictable manner.
A fossils of an organism the existed for only a short period of time, were common, and lived in many areas around the world.
When a rock layer is missing from one area of a rock bed. This may be caused by erosion or plate movement.
When molten rock cuts through sedimentary rock layers and cools into igneous rock. The igneous rock layer is younger than the sedimentary layers it cuts through
Verticales
Processes that shaped the earth in the past are the same processes that shape the earth now.
In undisturbed sedimentary rock layers, older layers of rock lie beneath younger rock layers.
Describes the age of a fossil or event in comparison to other fossils or events.
The actual age of a fossil, rock layer or how long ago an event occurred.
Layers of sedimentary rocks the record how species change over time and show hoe different species relate to one another.