Assignment 17: The Dating of Rocks, Fossils, and Geologic Events-Absolute Dating

Introduction

Geologists generally know the age of a rock by determining the age of the group of rocks, or formation, that it is found in. 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.

Absolute dating places events or rocks at a specific time. If a geologist claims to be younger than his or her co-worker, that is a relative age. If a geologist claims to be 45 years old, that is an absolute age. The nuclear decay of radioactive isotopes is a process that behaves in a clock-like fashion and is thus a useful tool for determining the absolute age of rocks. Radioactive decay is the process by which a “parent” isotope changes into a “daughter” isotope. Rates of radioactive decay are constant and measured in terms of half-life, the time it takes half of a parent isotope to decay into a stable daughter isotope.

Directions: 

1) This assignment is designed to assist you in learning the concepts of this module as well as assess your understanding and application of the content. Since this assignment is a combined Formative and  Summative Assessment of the module, it is considered a high-stakes assignment and will have a significant impact on your grade. To ensure that you understand and can apply the content, you will be provided two (2) opportunities to complete this assignment with the highest grade being kept as your final grade. Both attempts must be completed and submitted before the due date or the late policy will be applied to both submissions. This is a setting in Canvas I cannot control. No modifications will be made as you have been made aware of this setting. 

2) This assignment has no time limit and does not have to be completed in one sitting. Please do not click Submit Assignment until you have completed it. This assignment must be completed by the due date or the 10%/ day late policy will be applied to your grade. 

3) To begin this assignment, click the "Take the Quiz" button below.