Lateral continuity: The principle of lateral continuity states that sediments generally accumulate in continuous sheets within a given region.If today you find a sedimentary layer cut by a canyon, then you can assume that the layer once spanned the area that was later eroded by the river that formed the canyon.If a fault cuts across and displaces layers of sedimentary rock, then the fault must be younger than the layers.But if a layer of sediment buries a fault, the sediment must be younger than the fault.From these data, we can deﬁne the range of speciﬁc fossils in the sequence, meaning the interval in the sequence in which the fossils occur.
Different ways to correlate: -Physical continuity- can physically trace a rock unit from one area to another.
The succession of events in order of relative age that have produced the rock, structure, and landscape of a region is called the geologic history of the region.
We can use these principles to determine relative ages of the features.
Building from the work of Steno, Hutton, and others, the British geologist Charles Lyell (1797–1875) laid out a set of formal, usable geologic principles.
These principles continue to provide the basic framework within which geologists read the record of Earth history and determine relative ages.