4 relative dating principles dating someone who is bipolar side effects

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.

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.

They then go further by interpreting the formation of each feature to be the consequence of a specific geologic event.

Examples of geologic events include: Deposition of sedimentary beds; erosion of the land surface; intrusion or extrusion of igneous rocks; deformation (folding and/or faulting); and episodes of metamorphism.

If sediments were deposited on a steep slope, they would likely slide downslope before they could be buried and lithified.

With this principle in mind, geologists conclude that examples of folds and tilted beds represent the consequences of deformation after deposition.

Cross cutting relations: The principle of cross-cutting relations states that if one geologic feature cuts across another, the feature that has been cut is older.

For example, if an igneous dike cuts across a sequence of sedimentary beds, the beds must be older than the dike.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.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.Principle of baked contacts: The principle of baked contacts states that an igneous intrusion “bakes” (metamorphoses) surrounding rocks, so the rock that has been baked must be older than the intrusion.

Tags: , ,