Start Relative age dating practice problems

Relative age dating practice problems

The Permian through Jurassic stratigraphy of the Colorado Plateau area of southeastern Utah is a great example of Original Horizontality and the Law of Superposition, two important ideas used in relative dating.

Purpose: to establish the nature and rate of landscape evolution by determining the relative or absolute times when soil or rock surfaces where exposed by erosion, deglaciation or tectonism; constructed by deposition or tectonism; or exposed at the surface prior to burial by sediments or extrusive rock.

Relative (floating) age: is known only with respect to other landforms or surfaces; the chronology floats in time until referenced to an absolute date.

Volcanic rocks – such as tuff and basalt – can be used in dating because they are formed at a particular moment in time, during an eruption.

This problem is now reduced by the careful collection of samples, rigorous crosschecking and the use of newer techniques that can date minute samples.

From top to bottom: Rounded tan domes of the Navajo Sandstone, layered red Kayenta Formation, cliff-forming, vertically jointed, red Wingate Sandstone, slope-forming, purplish Chinle Formation, layered, lighter-red Moenkopi Formation, and white, layered Cutler Formation sandstone.

Photo from Glen Canyon National Recreation Area, Utah.

For example, the correlation of soil series, rock units, fluvial terraces or glacial moraines give a chronology of geologic events relative to one and other.


 
Dzisiaj jest:
08-Nov-2019 06:38