Based on petrophysical analysis, Average porosity (FA) and Effective porosity
for the Amb Formation (FE) increased towards northeast and decreased towards southwest.
Generally, porosity has two main types: total porosity and effective porosity
. Total porosity is defined as the ratio of the entire pore space in a rock to its bulk volume (Nnaemeka 2010), or the porosity derived directly from the logs without correction for the clay content.
Figure 2 shows best fit linear curves for uniaxial compressive strength, effective porosity
, and Young's modulus (E) of core samples.
Timonen, "Permeability and effective porosity
of porous media," Physical Review E: Statistical, Nonlinear, and Soft Matter Physics, vol.
and Coefficient of Water Absorption.
Increase in effective porosity
, supported by decrease in bulk and grain density, and slight decrease in sample weight, due to the dissolution of minor carbonate cement, displacement of clay cement after the experiment and minor increase in microfractures in grains, were determined after the alteration experiment in the samples from this structure (Tables 3, 4, Figs 3, 4).
An effective porosity
was employed when approximating the fluid flow resistance because not all pores were open and well connected between each other for gas flow.
Effective Effective porosity
of ceramic body porosity of defines the amount of effectively working ceramic body pores and capillaries.
These circumstances suggest considering not the total but the effective porosity
, which is the fraction of pores that can contribute to fluid flow, considering only the connected pores [1-7].
This is due to the effective porosity
and lower density gas effect on rigidity leading to a slight steeping of the "sandstone line" slope.