A combination of sieve and LPSA analysis is recommended to generate an accurate particle size distribution. For samples comprised of coarse-grained particles, sieve analysis is recommended. For samples with very fine particles, LPSA is recommended.
Particle Size Distribution
Particle size distribution may be determined either by Laser Particle Size Analysis (LPSA) or by conventional sieving. Results are presented as tabulated data and particle size distribution curves. The data is commonly used to support Petrography and well engineering studies.
Sieve Analysis vs. Laser Particle Size Analysis (LPSA)
A combination of sieve and LPSA analysis is recommended to generate an accurate particle size distribution. For samples comprised of coarse-grained particles, sieve analysis is recommended. For samples with very fine particles, LPSA is recommended.
Sand Fraction Analysis
The sand log directly measures the sand-sized fraction from cuttings and cores. The disaggregation technique, similar to that used for the foraminifera sample preparation involves the separation of the sands from the clays. The processed sample weight is then compared to the original weight of the cleaned cuttings to calculate the percent sand-sized fraction. Benefits of the sand fraction analysis are
- Quantifiably determine sand/shale percentages
- Can be derived from archived samples whenever needed
- Aids in the determination of the volume of shale (Vsh)
- Provides resolution of sand development in laminated sequences
- Determines rock properties directly rather than indirectly
- Aid the biostratigrapher in quantitative fauna abundance determinations