What is the primary difference between compression marks and scraping marks?

The primary difference between compression marks and scraping marks lies in the manner in which they are produced. Compression marks occur when an object exerts pressure on a surface, causing a deformation that results in an impression. This is typically seen in softer materials that can be indented under pressure, such as soil or certain types of plastics.

On the other hand, scraping marks are created when an object slides over a surface, effectively removing or displacing material in a manner that results in scratches or grooves. This type of mark indicates a different interaction between the object and the surface than that seen with compression marks.

Understanding this distinction is essential in crime scene analysis, as it helps investigators determine the nature of the objects involved and the dynamics of the incident being investigated. This knowledge can aid in reconstructing events and corroborating evidence found at a crime scene.