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Relative Dating of rock layers tells us that the deeper we dig - the older the rock gets.

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Relative Dating of rock layers tells us that the deeper we dig - the older the rock gets.

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Fossil is an impression left by the original organism - mold 

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Fossil is an impression left by the original organism - mold 

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A mold is the impression and void (space, hole) that an organism or organism's body or body part leaves in the sediment. ... A cast is made of different material than amold. Both casts and molds are types of fossils. Sometimes the mold and cast are found together, although molds are more than casts.

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A fossil trackway is a type of trace fossil, a trackway made by an organism. Many fossil trackways were made by dinosaurs, early tetrapods, and other quadrupeds and bipeds on land. ... Some basic fossil trackway types: footprints.

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Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization.

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Organisms buried in sediment may decay or dissolve away leaving a cavity or mold. If the space is subsequently filled with sediment, an external cast can be made.Molds and casts are three dimensional and preserve the surface contours of the organism.

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In physics and systems theory, the superposition principle, also known as superposition property, states that, for all linear systems, the net response caused by two or more stimuli is the sum of the responses that would have been caused by each stimulus individually.

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Uniformitarianism is defined in the authoritative Glossary of Geology as "the fundamental principle or doctrine that geologic processes and natural laws now operating to modify the Earth's crust have acted in the same regular manner and with essentially the same intensity throughout geologic time