Radiometric dating of sedimentary rocks

radiometric dating of sedimentary rocks

How do scientists date sedimentary rocks?

Scientists believe they can indirectly date sedimentary rocks using radiometric dating if they find igneous or metamorphic rock imbedded in or around a sedimentary rock layer. This of course presupposes that radiometric dating works consistently as a dating technique in the first place.

What is the difference between radiometric dating and sedimentary dating?

Radiometric dating determines how long ago the liquid rock solidified into solid rock. Sedimentary rock on the other hand consists of sedimentary particles which were removed and deposited somewhere else by some sort of fluid (generally wind and water).

How does redeposition affect radiometric dating?

In addition, the redeposition process upsets the conditions necessary to achieve accurate results through radiometric dating. Scientists believe they can indirectly date sedimentary rocks using radiometric dating if they find igneous or metamorphic rock imbedded in or around a sedimentary rock layer.

How do geologists determine the age of a rock?

When minerals get subducted into the Earth and come back as volcanic magmas or ash, this essential re-sets the radiometric clock back to zero and therefore a reliable age date is possible.

How do scientists determine the age of sedimentary rocks?

From there, scientists estimate the absolute ages of sedimentary rocks that they couldn’t otherwise date with radiometric dating. Then, once scientists have figured out how old sedimentary rocks are, they can conclude the age of fossils. This is because the fossils are the same age as the rocks that contain them.

How do scientists date rocks and fossils?

Scientists use two approaches to date rocks and fossils. Relative age dating is used to determine whether one rock layer (or the fossils in it) are older or younger than another base on their relative position: younger rocks are positioned on top of older rocks.

Can sedimentary rocks be dated radiometrically?

Most ancient sedimentary rocks cannot be dated radiometrically, but the laws of superposition and crosscutting relationships can be used to place absolute time limits on layers of sedimentary rocks crosscut or bounded by radiometrically dated igneous rocks.

What is the best way to describe sedimentary rocks?

Imagine your laundry basket—the dirty clothes you wore last weekend sit at the bottom, but todays rest on top of the pile. The concept for sedimentary rocks is the same. Older rocks are on the bottom, younger ones are on top.

Do Geologists use radiometric dating to determine the age of rocks?

Geologists do not use carbon-based radiometric dating to determine the age of rocks. Carbon dating only works for objects that are younger than about 50,000 years, and most rocks of interest are older than that.

How is the age of formations marked on a Geologic Calendar?

The age of formations is marked on a geologic calendar known as the geologic time scale. Development of the geologic time scale and dating of formations and rocks relies upon two fundamentally different ways of telling time: relative and absolute.

How do scientists date rocks and fossils?

Scientists use two approaches to date rocks and fossils. Relative age dating is used to determine whether one rock layer (or the fossils in it) are older or younger than another base on their relative position: younger rocks are positioned on top of older rocks.

Can a geologist tell the age of an object?

Listen - most geologists can do the simple stuff, like - ‘if it’s in a rock layer under that other one, then the layer underneath is older’. We can ALL do that. But accurate ages? Take it to people who have the right tools, which are specialists.

Related posts: