Measuring Porosity of a Rock Using Helium Prosimeter

Contents

1-Abstract 2

2-Introduction 3

3-Theory 4

3.1-Total and effective porosity: 4

3.2Primary and Secondary porosity: 5

4- Experimental Set-up and Procedure 5

4.1-Materials and equipment 5

4.2- Experimental set-up and procedure 5

5-Results and calculations 7

6-Discussion and conclusion 8

6.1- Discussion of the results 8

6.2- Conclusion 8

7- References 9

1-Abstract

The aim of this report is to be familiar with the basic procedures of preparing rock samples and to measure the density of and porosity of rock samples.

Firstly the rock size and mass was measured to determine the density and bulk volume using an electronic ruler and mass balance. Then using the helium porosimeter the grain volume of each core plug sample was measured. Each of these measurements were repeated three times and then averaged for precision sake. The porosity was then calculated by subtracting the grain volume from the bulk volume, to determine the pore volume, and then dividing by the bulk volume. The porosity results for all the samples were reasonable except for sample 1 and 6 for which the porosity is calculated to be in negative % and make no logic. These possible reasons for these inaccurate results are that the group made high errors in reading the measurements or did the experiment in a wrong method.

2-Introduction

For the storage of oil and gas in any reservoir rock presence of porosity is vital. However, the degree of porosity in any rock depends upon various factors. But quality of reservoir rock, either good or poor, rests largely on porosity.

Porosity is the small voids and space between the grains of the rocks and often denotes with percent. Mathematically it is volume of the voids divided by total volume of the rock. Knowledge of porosity is of extreme importance for understanding the reservoir characteristics and behaviour. (Schlumberger, 2012)

Conventional laboratory experiments can be used to determine the porosity of the...