The Archimedes method is used to determine the volume of an irregular shaped solid object. This is done by determining the dry mass of an object (which is given), the fully water saturated mass, measured with the Kern 572, and the mass of the sample when hanging in a water-filled bowl. Both measurements – the saturated and hanging-mass in a water-bowl – were done five times each by about 19.5°C air temperature and about 18°C water temperature. For this experiment we used two samples: G1 is a black stone with small mica particles and bigger white quartz inclusions. This stone is coarse-grained and compacted and therefore it could be a gabbro. G2 is a greenish sandstone with small particles and lesser compaction. The results of the measurements are shown in table 1. [...]
Table of Contents
I. Archimedes Principle measurement
II. Gaspycnometer measurment
III. Geopycnometer measurment
IV. Conclusion
Research Objectives and Topics
This report aims to evaluate and compare three distinct methods for determining the physical properties of rock samples, specifically focusing on volume, density, and porosity calculations through experimental analysis.
- Application of the Archimedes principle for mass and volume determination.
- Utilization of automated gas pycnometry for precise density measurements.
- Analysis of rock sample characteristics using GeoPyc displacement technology.
- Comparative evaluation of measurement reliability and error margins across different techniques.
Excerpt from the Book
I. Archimedes Principle measurement
The Archimedes method is used to determine the volume of an irregular shaped solid object. This is done by determining the dry mass of an object (which is given), the fully water saturated mass, measured with the Kern 572, and the mass of the sample when hanging in a water-filled bowl. Both measurements – the saturated and hanging-mass in a water-bowl – were done five times each by about 19.5°C air temperature and about 18°C water temperature. For this experiment we used two samples: G1 is a black stone with small mica particles and bigger white quartz inclusions. This stone is coarse-grained and compacted and therefore it could be a gabbro. G2 is a greenish sandstone with small particles and lesser compaction. The results of the measurements are shown in table 1.
Summary of Chapters
I. Archimedes Principle measurement: This chapter introduces the manual method of determining rock volume and density through water displacement and provides the calculated results for two specific rock samples.
II. Gaspycnometer measurment: This section details the automated process of using helium gas displacement to determine dry weight and density, highlighting the technical advantages of using noble gases.
III. Geopycnometer measurment: This chapter describes the use of GeoPyc technology involving graphite-like powder to determine bulk volume and porosity, emphasizing the necessity of precise calibration.
IV. Conclusion: The final chapter synthesizes the findings, comparing the reliability of the three methods and discussing potential error sources like temperature fluctuations and manual handling.
Keywords
Archimedes principle, Gaspycnometer, Geopycnometer, Petrophysics, Density, Porosity, Gabbro, Sandstone, Error propagation, Bulk volume, Helium displacement, Rock samples, Laboratory analysis, Measurement reliability, Material characterization
Frequently Asked Questions
What is the fundamental purpose of this laboratory report?
The report serves to experimentally compare three scientific methods for determining the petrophysical properties—specifically density, volume, and porosity—of two specific rock samples.
What are the primary thematic areas covered?
The main themes include hydrostatic weighing, gas-based displacement techniques, solid medium displacement (powder pycnometry), and the statistical analysis of measurement uncertainties.
What is the core research goal?
The goal is to test how different measurement techniques perform regarding accuracy and to identify which method provides the most reliable data for classifying rock samples like gabbro and sandstone.
Which scientific methods are employed?
The study utilizes the Archimedes principle, AccuPyc 1330 gas pycnometry, and GeoPyc 1360 powder displacement method, supported by Gaußian error propagation analysis.
What is discussed in the main body of the work?
The main body presents the step-by-step experimental procedures, the mathematical formulas used for calculations, the raw data, and the resulting density and porosity values for the samples.
Which keywords best characterize this work?
Key terms include Archimedes principle, petrophysics, gas pycnometry, bulk density, porosity, error propagation, and rock sample classification.
Why is helium preferred in the Gaspycnometer measurement?
Helium is used because it is an inert noble gas with small molecules that can diffuse quickly into even the smallest pores without causing unwanted chemical reactions with the sample surface.
What limitations were identified in the Archimedes method?
The limitations include significant potential for human error during manual handling (transporting samples to scales, drying/toweling) and the fact that it only accounts for surface-connected pores.
How do the results for sample G1 compare to geological literature?
The calculated density for G1 aligns well with literature values for gabbro, supporting the identification of the sample as a highly compacted metamorphic rock.
- Quote paper
- Amalia Aventurin (Author), 2013, Archimedes Principle, Gaspycnometer and Geopycnometer, Munich, GRIN Verlag, https://www.hausarbeiten.de/document/272607
