Figure 1. A nucleus of uranium (the parent nuclide) undergoes α decay to form . Figure 3. This table summarizes the type, nuclear equation, representation, . The radioactivity of carbon provides a method for dating objects that were a . What are the types of radiation emitted by the nuclei of radioactive elements?. Page #. Scientific Investigation. 1. Mapping the Earth. 4. Minerals and Rocks. 7 Date, time and location of your Earth Science SOL 3 and a mass of 30g. What is the density? D = 30g / 20cm. 3. = g / cm. 3 Scientific Method Definitions: .. Identify the river stages and give 3 facts about Soil Profile: Briefly describe. Radioactive Dating D Outline the method for dating rocks and fossils . Mass of individual atoms Lesson 1 – introduction to project and atomic structure.
A colorful geological map, preferably of your area on wall, or as an overhead color transparency. The Deep Time activity envelopes one for each team of two, with isotope strips in them The Deep Time handouts: The pre- and post-test quizzes, ready to hand out optional A scaled time-line for the solar system around the classroom, if possible see our Time Machine lesson.
How sure are we about these ages? How do we measure the ages of rocks?
Count "atoms" in simulated rock samples of different "ages". Students relate half-lives of radioisotopes to the application of dating rocks.
Sequence all known radioisotopes with half-lives greater than 1 million years; look for pattern, showing that all longer-lived isotopes are still with us, and the shorter-lived ones are not, indicating a finite age of our solar system, and that its age must be in the millions or billions of years. Do the Deep Time lesson, which emphasizes why we are so confident of geological age dates.
Do the Virtual Age Dating Tutorial onlinefor further reinforcing of half-life concept and how this is applied to dating rocks.
This is especially helpful in explaining how isochrones work, and why they are so compelling. Fossils that can be used in this way are called index fossils, and rock layers with the same index fossils in them can be correlated.
To be considered an index fossil, it must meet 3 criteria: The fossilized organism must be easily recognizable. It must be easy to ID and look unique.
The fossil must have lived for only a short time, so that it appears in only horizontal layer of sedimentary rocks. Often you will be required to use these characteristics to decide which fossils in rock outcrops can be used as index fossils. The diagram below shows several rock outcrops separated by large distances.
In each outcrop are several fossils.
Lesson: evolution: Date a Rock
Which of the fossils shown is an index fossil? When choosing the right index fossil we can reinterpret the characteristics of index fossils to help us: Easily Recognizable is usually not an issue in these problems because the diagram clearly illustrates each fossil.
Can be eliminated because it shows up in two different layers in the first outcrop. Therefore we can eliminate all of these from the diagram. Can be eliminated because it shows up in two different layers in the second outcrop. Can be eliminated because it is not in the first, second, or third outcrops.