Inferring Relative Permeability from Resistivity Well Logging

Only available on StudyMode
  • Download(s) : 681
  • Published : July 20, 2010
Open Document
Text Preview
Inferring Relative Permeability from Resistivity Well Logging Introduction

Permeability is a chattel of a spongy medium that measures the capacity of a substance to transmit fluids. Generally, permeability that is applied in petroleum industry is steady in Darcy’s flow equation which compares pressure gradient, flow rate and fluid properties. However, a formation has permeability regardless if the fluid is flowing or not, and as result, a straight measurement of permeability necessitates a dynamic procedure rather than a static procedure. In the past, well logs have been used to approximate permeability through correlations that is linked to a general logged property called porosity. Perm-porosity correlations are formed from interior and changes to well log porosity. In most cases, these correlations are semilog in nature; that is in form of y = axb. The other correlations try to approximate effectual perm by including irreducible petroleum saturation approximated from Archie’s equation and resistivity logs. Majority of well logging environments are normally in static states, where incursion of mud filtrate into the permeable formations which concludes after the well is logged.

One of the significant factors in geothermal reservoir engineering is steam-water relative permeability. However, it is not easier to measure steam-water relative permeability due to phase transformation and mass transfer as pressure changes. There are some physicians who argued that steam-water relative permeability can be calculated from the data of capillary pressure. This method gives an easier and an economical approach to get steam-water relative permeability when contrasted with experimental method. The demerit side of this method is the necessity of measuring the steam-water capillary pressure that can consume a lot of time and also been difficult in most cases. Consequently, it’s beneficial for scientists and engineers to have a technique in order to conjecture steam-water...
tracking img