PMUG Magazine
Vol.21
Vol.20
Article
| Title | Number of grains required to examine heavy minerals by SEM-EDX for forensic discrimination of small quantity of coast sand and proposal of its analytical method |
| Author | Ritsuko SUGITA |
| Keywords | coast sand, heavy minerals, forensic geology, SEM- EDX |
| Abstract | Sediments recovered from crime scenes, suspects, and victims are crucial evidence in linking individuals to a crime. Coastal sand is one such type of evidence but presents unique challenges compared to soil. The grains of coastal sand are constantly moved and rubbed against each other by waves. This movement also sorts the grains by size and weight, and removes surface coatings like organic matter and iron oxide. As a result, some common forensic soil comparison methods, such as color examination and the ratio of light to heavy minerals, are less applicable to coastal sand samples. However, heavy mineral assemblages may serve as a useful indicator for distinguishing these sand samples, despite the effects of mineral sorting. This study examines the necessary sample sizes to estimate the ratios of minerals in the pyroxene group. The coastal sand samples analyzed predominantly contain heavy minerals from the pyroxene group. Using SEM-EDX analysis, the minerals are classified as orthopyroxene (Opx), clinopyroxene (Cpx), ilmenite, and magnetite. The ratio of Opx to Cpx in 50 to 70 pyroxene grains is sufficient to characterize the sampling sites. SEM-EDX provides more objective and reliable results in mineral identification than traditional microscope observations, reducing examiner bias and dependence on skill level. |
| Names of academic journals, etc. | Geopol. Sci., Med. Geol. and Urban Geol. 2024 Vol.20, p. 9-14 |
| Received | 17 Oct. 2024 |
| Accepted | 19 Dec. 2024 |
Photo
| Title | Traces of the 2024 Noto Peninsula earthquake and heavy rains |
| Author | Atsuko FUKUYAMA and Kenichi FUKUYAMA |
| Names of academic journals, etc. | Geopol. Sci., Med. Geol. and Urban Geol. 2024 Vol.20, p.1-8 |
| Received | 15, Nov. 2024 |
Vol.19
Vol.19 No.3/4 2023
Vol.19 No.1/2 2023
Vol.18
Vol.18 No.3/4 2022
Vol.18 No.1/2 2022
Vol.17
Vol.17 No.3/4 2021
Vol.17 No.1/2 2021
Vo.16
-
-
Vol.15
-
-
Proceedings of the Symposium on Geo Environments and Geo Technics
2011 -
- 30th
- 29th
- 28th
- 27th
- 26th
- 25th
- 24th
- 23rd
- 22nd
- 21st
2001 - 2010
- 20th
- 19th
- 18th
- 17th
- 16th
- 15th
- 14th
- 13th
- 12th
- 11th
1991 - 2000
- 10th
- 09th
- 08th
- 07th
- 06th
- 05th
- 04th
- 03rd
- 02nd
- 01st