Unit 7: Vocabulary Review
Terms in this set (15)
Older layer is tilted, eroded, and then a younger layer forms on top
a formation of stratified rock raised up, by folding into a broad arch so the layers slope down on both sides from a common crest
A rock fragment or grain resulting from the breakdown of larger rocks
Erosion between two layers of sediment
a geologic feature in which molten rock has been injected into pre-existing rock. In the diagram, "A" is the intrusion.
Law of Cross-Cutting Relationships
A principle holding that an igneous intrusion or fault must be younger than the rocks it intrudes or cuts across.
Law of Lateral Continuity
sedimentary rocks are laterally continuous over large areas.
Law of Original Horizontality
layers of sediment are originally deposited horizontally under the action of gravity.
Law of Superposition
In an undisturbed rock column the layers on the bottom will be the oldest and the youngest rocks will be on the top.
An unconformity in which stratified sedimentary rocks overlie an erosion surface cut into igneous or metamorphic rocks.
the disconformity (the erosion surface) is parallel to the layering of both rock layers
Principle of Superposition
a principle holding that in a vertical sequence of undeformed sedimentary rocks, the relative ages of the rocks can be determined by their position in sequence-oldest at the bottom followed by successively younger layers.
A fold of rock layers that slope upward on both sides of a common low point.
A break in the geologic record represented by an erosional surface separating younger strata from older rocks.
The theory stating geological processes that took place in the past are generally similar to those that occur now