Question

the mineral composition of soil samples can reveal a wealth of information about their origin. forensic geologists often rely on the unique signatures of minerals such as quartz, feldspar, and mica to trace the provenance of soil found at crime scenes. a recent study by dr. jennifer morton and her team at the university of edinburgh has demonstrated the efficacy of using rare earth element (ree) analysis to pinpoint the geographic source of soil samples with remarkable precision. by examining the ratios of elements like neodymium and samarium, the researchers were able to match soil samples to specific locations within a 10 - kilometer radius. this method has proven particularly useful in cases where traditional techniques, such as particle size distribution and color analysis, fall short.
3 ◇ mark for review
what is the main purpose of the text?
a to highlight the limitations of traditional soil analysis techniques in forensic geology.
b to discuss a new method for determining the geographic origin of soil samples.
c to argue for the adoption of rare earth element analysis in more forensic investigations.
d to describe the mineral composition of soil samples in various geographic locations.

Explanation:

• Option A: The text does not focus on highlighting limitations of traditional techniques; it introduces a new method, so A is incorrect.
• Option B: The text presents a recent study by Dr. Morton's team using rare earth element (REE) analysis to determine soil samples' geographic origin, which is a new method. This matches the main purpose.
• Option C: The text does not argue for adoption in more investigations; it just shows the efficacy of the new method, so C is incorrect.
• Option D: The text is not about describing mineral composition across locations but about a method to determine origin, so D is incorrect.

Answer:

B. To discuss a new method for determining the geographic origin of soil samples.