« previous next »

Author Question: How were absolute ages added to the geologic time scale in the 20th century? What will be an ideal ... (Read 40 times)

tsand2

  • Hero Member
  • *****
  • Posts: 520
on: Jul 15, 2018
How were absolute ages added to the geologic time scale in the 20th century? What will be an ideal response?

Question 2

How was the geologic time scale developed in the 19th century? What will be an ideal response?


stallen

  • Sr. Member
  • ****
  • Posts: 336
Reply #1 on: Jul 15, 2018
Answer to Question 1

Thousands of absolute ages were added to the relative time scale that had been created. Since
sedimentary rocks cannot be radiometrically dated, interbedded volcanic rocks and igneous intrusions
that could be dated provided boundaries of the subdivisions of the geologic time scale.



Answer to Question 2

Geologists applied relative-dating methods to rock outcrops in England and western Europe, and they
put together the major geologic time units. They made a composite geologic section, using the
principles of superposition and fossil succession. The rocks are in sequential order, but there are no
absolute ages.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

As many as 20% of Americans have been infected by the fungus known as Histoplasmosis. While most people are asymptomatic or only have slight symptoms, infection can progress to a rapid and potentially fatal superinfection.

Did you know?

Intradermal injections are somewhat difficult to correctly administer because the skin layers are so thin that it is easy to accidentally punch through to the deeper subcutaneous layer.

Did you know?

IgA antibodies protect body surfaces exposed to outside foreign substances. IgG antibodies are found in all body fluids. IgM antibodies are the first type of antibody made in response to an infection. IgE antibody levels are often high in people with allergies. IgD antibodies are found in tissues lining the abdomen and chest.

Did you know?

More than 30% of American adults, and about 12% of children utilize health care approaches that were developed outside of conventional medicine.

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates's recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Milking reindeer in the 19th century Milking reindeer in the 19th century
Neurological Flow Sheet, Including Glasgow Coma Scale Neurological Flow Sheet, Including Glasgow Coma Scale
Scale used to measure pupil size in millimeters. Scale used to measure pupil size in millimeters.
Test for Depressive Symptoms: CED Scale Test for Depressive Symptoms: CED Scale
Determining Richter Scale Magnitude Determining Richter Scale Magnitude
Absolute Stability Absolute Stability
Video: Mitosis step-by-step

For a complete list of videos, visit our video library