Warm Up Objective: Scientists will describe forensic geology by analyzing soil evidence. What is the topic? What will you be doing? Why is this important? How will you know if you have done well?

Warm Up Objective: Scientists will describe forensic geology by analyzing soil evidence. What is the topic? Forensic geology What will you be doing? Analyzing soil evidence Why is this important? Evidence for convictions, future career choice How will you know if you have done well? Able to describe forensic geology; analyzed soil evidence

Analyzing Soil Evidence Make some observations of what you can see in the soil. Note the color, texture, odor, and general appearance. Use a magnifying glass. Note any presence of vegetation or other unusual materials. Observe the soil sample with the UV light. Write your observations. Measure the pH of the soil. Add a small amount of soil to the well plate, then add 3 drops of Universal Indicator. Compare to color chart. Record the pH number and whether that is acidic, neutral, or basic. Measure the reaction of a small sample of soil to acid. Add a small amount of soil to the well plate. Add 3 drops of HCl to the sample. Look carefully for any presence of gas bubbles and record your observations. Test for the presence of blood. In this case, we will use chemical indicators. Take a swab and run it through the soil. Add one drop of 70% ethanol to the swab. Add one drop of Blood Indicator #1 to the swab. Add one drop of Blood Indicator #2 to the swab. If there is a color change, blood is present.

Analyzing Soil Evidence Soil Analysis Observations Color   Texture Odor    General Appearance Unusual materials / vegetation UV Light observations Reaction to acid Presence of Blood

Analyzing Soil Evidence This is soil that was found at the scene of a crime. Based on the results, what do you think happened? Answer in at least one paragraph, using evidence from your data table. As a bonus, you can write a short story to explain the evidence found in this soil.   You did not do all the tests that are possible for soil analysis. What else could be done, and what could those tests indicate?  How is soil useful to forensic scientists?

Stations Complete the stations from yesterday as necessary.