تسجيل الدخول

تسجيل

REPRESENTATIVE SAMPLES OF SOIL

المؤلف:  Max M. Houck، Jay A. Siegel

المصدر:  Fundamentals of Forensic Science

الجزء والصفحة:  432

2026-08-18

36

REPRESENTATIVE SAMPLES OF SOIL

Soil, like some other types of evidence, may occur in large quantities in a given case. When this happens, it may be necessary to make some decisions about how much of the exhibits will actually be analyzed. It is usually not necessary to examine all of the soil in an exhibit as long as the samples taken from the bulk exhibit are representative of the whole. There are a number of ways of determining how many samples to take, their size, etc., but the first consideration is to decide if and how an exhibit of soil is to be homogenized so that the samples taken will be representative. This presents some unique situations with soil evidence. One of the most important tests done on soils is to determine the particle size distribution. Some soils are coarse and contain large chunks of material, whereas others are finely divided. If a known and unknown sample of soil came from the same location, their particle size distributions are usually similar. This means that the determination of particle size distribution must be made before the soil is pulverized in an attempt to homogenize it. In this context, particle size distribution is an inventory of the various sizes of the particles present in a sample of soil. Once the particle size distribution is determined (see below for a discussion about how this is done), then the soil can be crushed and pulverized to make it consistent throughout so that samples taken for analysis represent the bulk exhibit and the physical and chemical analyses on the samples can be extrapolated to the bulk sample.