Author Question: How were absolute ages added to the geologic time scale in the 20th century? What will be an ideal ... (Read 51 times)

tsand2

  • Hero Member
  • *****
  • Posts: 520
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
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
 

Did you know?

Stroke kills people from all ethnic backgrounds, but the people at highest risk for fatal strokes are: black men, black women, Asian men, white men, and white women.

Did you know?

The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

Did you know?

Drug-induced pharmacodynamic effects manifested in older adults include drug-induced renal toxicity, which can be a major factor when these adults are experiencing other kidney problems.

Did you know?

People often find it difficult to accept the idea that bacteria can be beneficial and improve health. Lactic acid bacteria are good, and when eaten, these bacteria improve health and increase longevity. These bacteria included in foods such as yogurt.

For a complete list of videos, visit our video library