Soil: a Silent Witness
Got a Crime to Solve? Call in the Soil Scientists!
April 1856 - Berlin, Germany
The earliest documentation of using soil comparisons for forensic case solving purposes was in April of 1856. Professor Ehrenberg, of Berlin, collected samples of sandy soil along a railway line. By using a light microscope, he was able to examine different features of the sandy soil particles, such as color and shape.
September 2000 - Adelaide, Australia
Two woman disappeared from their home outside of Adelaide. When the police investigated, they found blood and broken glass inside the home, along with a missing car. The car was found 100 miles from the home the next day. With no leads, police turned to a team of soil scientists from CSIRO for any information. By analyzing the soil under a microscope, the soil scientists were able to hypothesize that the soil had been exposed to human activity similar to mining. Along with their mineralogical analysis report revealing the presence of talc, a mineral found only in the area's mountains and foothills, the soil scientists were able to point the investigation in the right direction.
Soil Analysis Techniques
Light Microscope
A light microscope is a simple, inexpensive technique that soil scientist uses to identify soil color, morphology, and shape.
X-Ray Diffraction (XRD)
This is a technique that identifies crystalline minerals by the patterns their atoms scatter back when X-rays are directed at the sample.
Synchrotron XRD
This is a technique that is more powerful than the X-ray diffraction they can do in a lab, but it costs approximately $10,000 a day.
Chinese Dinosaur Eggs
Soil evidence can help in not only murder cases, but in other criminal cases as well. In one case that was cracked by the use of soil samples, two Australian collectors were being investigated for possessing suspected illegal Chinese dinosaur eggs. Soil scientists were able to analyze the soil sample on the egg and compare it to the American soil they claimed the egg came from. The soil scientists revealed that the egg did in fact originally come from China.