EBK ESSENTIALS OF GEOLOGY
EBK ESSENTIALS OF GEOLOGY
12th Edition
ISBN: 9780321957887
Author: Tasa
Publisher: VST
Question
Book Icon
Chapter 19, Problem 1GST
To determine

The reason regarding the Precambrian consisting of fewer divisions than the rest of the time scale (although it accounts for nearly 90 percent of the geologic time), by referring to Figure 19.3 in Chapter 19 in this textbook.

Expert Solution & Answer
Check Mark

Answer to Problem 1GST

The reason regarding the Precambrian era consisting of fewer divisions than the rest of the time scale is because of having less knowledge about this time period. The primary reason is the absence of fossils in Precambrian rocks; many of these rocks are concealed within continental interiors or have been destroyed by tectonic processes.

Due to the lack in complete geologic record from this time, it is difficult to divide this span into smaller increments without more detailed data

Explanation of Solution

The 4.5 billion years of the Earth’s history is marked by two major eons, namely the Phanerozoic Eon (in Greek, “visible life”), which started about 541 million years ago and the Precambrian Eon, which started approximately 4 billion years ago. The Precambrian Eon is further divided into Archaen, (‘archaios’ denotes ‘recent’) and Proterozoic Eon (‘proteros’ denotes ‘before’; ‘zoe’ denotes ‘life’).

Although, the Precambrian represents nearly 88 % of the Earth’s history, it is not divided into eras, periods and epochs. The reasons for the lack of detailed time scale are stated below:

  • Not knowing enough about the detailed Precambrian history. The past 10 years of the Earth’s history is very well-documented because of its fresh, least distorted, and most observable record. As we go further back in time, the clues and records are more fragmented.
  • The Precambrian was dominated by simple organisms like bacteria, algae, fungi, and worms. These organisms lacked hard parts which did not favor preservation. Owing to this reason, the Precambrian had very little fossil records.  Due to the lack of fossils, correlation with the exposed Precambrian rocks is usually difficult.

The Precambrian rocks are extremely old and are subjected to a great deal of change. Most of them are greatly distorted metamorphic rocks, broadly eroded and often hidden beneath the younger geological beds and thus, it makes the interpretation of the past environment difficult because of many clues being destroyed in the original sedimentary rocks.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
what would you do if you're working in a group and you notice that the group is not functioning productively (no work being done)
what kind of attitude or demeanor would you bring when getting to know supervisor or colleague
In this course, we examine how social, economic, political and cultural processes transform relationships between people and the spaces they inhabit. Globalization is one of the key processes shaping human geographies in the 21st century. Although globalization operates at a planetary scale, its effects are felt in the spaces and routines of daily life. For this assignment, you are asked you to observe and analyze how globalization manifests in your own everyday experiences. Objectives • • Apply core geographic concepts of place, space and scale • Identify concrete examples of how global processes shape local contexts • Develop skills in observation and analysis Instructions 1. Choose two aspects of daily life from the following list that you will use to explore the influences of globalization: ○ Material goods - commodities, food ○ Media & entertainment о Technology & communication о Social connections and relationships O Linguistic or cultural landscapes 2. For each aspect, identify…
Knowledge Booster
Background pattern image
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Applications and Investigations in Earth Science ...
Earth Science
ISBN:9780134746241
Author:Edward J. Tarbuck, Frederick K. Lutgens, Dennis G. Tasa
Publisher:PEARSON
Text book image
Exercises for Weather & Climate (9th Edition)
Earth Science
ISBN:9780134041360
Author:Greg Carbone
Publisher:PEARSON
Text book image
Environmental Science
Earth Science
ISBN:9781260153125
Author:William P Cunningham Prof., Mary Ann Cunningham Professor
Publisher:McGraw-Hill Education
Text book image
Earth Science (15th Edition)
Earth Science
ISBN:9780134543536
Author:Edward J. Tarbuck, Frederick K. Lutgens, Dennis G. Tasa
Publisher:PEARSON
Text book image
Environmental Science (MindTap Course List)
Earth Science
ISBN:9781337569613
Author:G. Tyler Miller, Scott Spoolman
Publisher:Cengage Learning
Text book image
Physical Geology
Earth Science
ISBN:9781259916823
Author:Plummer, Charles C., CARLSON, Diane H., Hammersley, Lisa
Publisher:Mcgraw-hill Education,