Table of Contents
How do you measure compressibility of a rock?
Rock compressibility is not measured in a conventional core analysis, but can be determined using hydrostatic or triaxial tests. In these tests, the core section is sealed in a rubber sleeve and placed lengthwise in a piston. Pressure is imposed on the rock matrix using the piston.
Which compressibility is important for reservoir performance estimation?
Rock compressibility is required for material balance calculations, reservoir simulation, and well test analysis.
What is compressibility test?
This test determines the pore volume compressibility of a rock sample under reservoir condition. The constant stress σ1 simulates the overburden while the radial stress σ3 is controlled in such a way that the radial deformation of the sample is zero throughout the test (uniaxial strain test).
How do you calculate compressibility of water?
The Compressibility of a Fluid formula is defined as the inverse of Bulk Modulus of Elasticity of the fluid and is represented as C = -((dV/V)/dP) or Compressibility of Fluid = -((Change in Volume/Fluid Volume)/Change in Pressure).
Which rock compressibility number is preferred by reservoir engineers?
Rock compressibility factor is very important for reservoir modelling. cf is typically in the range from 3 x 10-6 to 6 x 10-6 1/psi. Use the following data to determine volume change in reservoir rock per 100 psi of pressure drop. Abhijit Y.
What is compaction drive?
PetroWiki. A drive mechanism in a weak zone that displaces fluid by reducing the overall volume of the formation.
What is reservoir compaction?
While all reservoirs undergo deformations during exploitation, compaction is the process in which the compressive strength of the rock is exceeded and plastic deformation occurs, resulting in irreversible reduction of porosity and permeability.
What is the unit of compressibility?
Usually, when we are talking about compressibility we can say that it is the inverse or reciprocal of the bulk modulus of elasticity. So if look at the unit of compressibility we are basically considering those of reciprocal pressure, Pa-1 or atm-1. The SI unit of compressibility is mostly given as m2/n.
How do you calculate compression index?
The Compression Index (Cc) is equal to the slope of the graph of pressure versus void ratio (log scale) [7]. Compression Index (Cc) for clay is in the range 0.258 to 0.968, while for laterite soil was in the range 0.101 to 0.940. Value of Compression Index (Cc) is different between each type of soil.
What are the three types of driven mechanism?
Drive mechanisms are determined by the analysis of historical production data, primarily reservoir pressure data and fluid production ratios. The three primary oil reservoir drive mechanisms are solution gas drive, gas cap drive, and water drive.
What is the symbol of compressibility?
where μ is the chemical potential. The term “compressibility” is also used in thermodynamics to describe deviations of the thermodynamic properties of a real gas from those expected from an ideal gas. Z can, in general, be either greater or less than unity for a real gas.
What is the compressibility factor Z?
The compressibility factor Z is defined as the ratio of the actual volume to the volume predicted by the ideal gas law at a given temperature and pressure. Z = (Actual volume) / (volume predicted by the ideal gas law)
What is a compression index?
Compression index (Cc) is used to predict the compressibility of soil and estimate how much settlement which is occurred due to loads of different engineering structures.
What is compressor index?
The compression index (Cc) is the slope of the linear portion of the pressure–void ratio curve on a semi-log plot, with pressure on the log scale (IS: 8009 – Part 1, 1976). This is a dimensionless parameter.
How do you calculate the compressibility factor for co2?
Hint: To solve this you can use the formula of compressibility factor which is, \[Z=\dfrac{PV}{nRT}\]. If the calculated compressibility factor is less than one then the gas is more compressible than ideal gas and if it is more than one, then the gas is less compressible than ideal gas.
How is rock compressibility measured?
Rock compressibility is not measured in a conventional core analysis, but can be determined using hydrostatic or triaxial tests. In these tests, the core section is sealed in a rubber sleeve and placed lengthwise in a piston. Pressure is imposed on the rock matrix using the piston. In a hydrostatic test, the pressure is the same in all directions.
What is the isothermal rock compressibility?
Jerry L. Jensen, in Practical Reservoir Engineering and Characterization, 2015 The isothermal rock compressibility is a measure of the change in rock volume or pore volume with a change in pressure at constant temperature and is defined as follows: in which PV is pore volume, V is total volume, and P is pressure.
What is bulk compressibility of rock?
Rock bulk compressibility is the change in volume of the bulk volume of the rock with a unit change in pressure. Pore compressibility is the fractional change in the pore volume of the rock with a unit change in pressure.
What are the different types of compressibility in rocks?
Three kinds of compressibility must be distinguished in rocks: Rock matrix compressibility Rock bulk compressibility Pore compressibility Rock matrix compressibility is the fractional change in volume of the solid rock materials (grains) with a unit change in pressure.