Question:
The Timur chart for estimating the permeability is the plot between
The Timur chart for estimating the permeability is the plot between
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In reservoir engineering, the Timur chart helps estimate permeability by analyzing combinations of porosity, water saturation, resistivity, and irreducible water saturation.
Updated On: Dec 2, 2025
- Porosity and Water Saturation
- True Resistivity and Water Saturation
- Porosity and Irreducible Water Saturation
- Porosity and True Resistivity
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The Correct Option is C
Solution and Explanation
Step 1: Understanding the Timur chart.
The Timur chart is used for estimating the permeability of a reservoir based on two key factors that influence its porosity and saturation. The chart provides a relationship between various reservoir parameters like porosity, water saturation, resistivity, and irreducible water saturation.
Step 2: Option Analysis.
- (A) Porosity and Water Saturation: This combination is related to the reservoir’s capacity to hold water, but not directly to permeability estimation via the Timur chart.
- (B) True Resistivity and Water Saturation: This is the correct relationship for estimating permeability. True resistivity is related to the ability of the rock to resist electrical flow, while water saturation helps in determining how much water is present in the pore spaces. This combination is typically used in the Timur chart.
- (C) Porosity and Irreducible Water Saturation: Irreducible water saturation is the fraction of water in the rock that cannot be removed, and porosity is the fraction of the rock that can hold fluid. This combination also works in estimating permeability.
- (D) Porosity and True Resistivity: While both factors affect permeability, this is not the main relationship used in the Timur chart.
Step 3: Conclusion.
Both (B) and (C) are correct, as these are the commonly used relationships in the Timur chart for permeability estimation.
The Timur chart is used for estimating the permeability of a reservoir based on two key factors that influence its porosity and saturation. The chart provides a relationship between various reservoir parameters like porosity, water saturation, resistivity, and irreducible water saturation.
Step 2: Option Analysis.
- (A) Porosity and Water Saturation: This combination is related to the reservoir’s capacity to hold water, but not directly to permeability estimation via the Timur chart.
- (B) True Resistivity and Water Saturation: This is the correct relationship for estimating permeability. True resistivity is related to the ability of the rock to resist electrical flow, while water saturation helps in determining how much water is present in the pore spaces. This combination is typically used in the Timur chart.
- (C) Porosity and Irreducible Water Saturation: Irreducible water saturation is the fraction of water in the rock that cannot be removed, and porosity is the fraction of the rock that can hold fluid. This combination also works in estimating permeability.
- (D) Porosity and True Resistivity: While both factors affect permeability, this is not the main relationship used in the Timur chart.
Step 3: Conclusion.
Both (B) and (C) are correct, as these are the commonly used relationships in the Timur chart for permeability estimation.
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