Determining pressure in subterranean formations
AssigneeSaudi Arabian Oil Company
InventorSimon A. Stewart
Life of this patent
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Abstract
A method for determining a pressure profile in a subterranean formation is described. The method includes drilling a wellbore in the subterranean formation; lowering a logging tool into the wellbore to measure resistivity values as a function of depth along the wellbore; identifying a plurality of porous zones from the wellbore based on petrophysical logs; converting the measured resistivity values to an amount of total dissolved solids for each of the plurality of identified porous zones; converting the amount of total dissolved solids to a pore fluid density; calculating a pressure based on a sum of the pore fluid densities derived along a length of the well; and generating a depth-based pressure profile.
Claims20
A method for determining a pressure profile in a subterranean formation, the method comprising:
- drilling a wellbore in the subterranean formation;
- lowering a logging tool into the wellbore to measure resistivity values as a function of depth along the wellbore;
- identifying a plurality of porous zones from the wellbore based on petrophysical logs, wherein identifying the plurality of porous zones further comprises characterizing each identified porous zone based on a porosity amount and a tolerable hole condition;
- converting the measured resistivity values to an amount of total dissolved solids for each of the plurality of porous zones;
- converting the amount of total dissolved solids to a pore fluid density;
- calculating a pressure based on a sum of the pore fluid densities derived along a length of the well;
- and
- generating a depth-based pressure profile.
A system for determining a pressure profile of a wellbore, the system comprising:
- a logging tool configured to be deployed in a wellbore to measure resistivity values as a function of depth along the wellbore;
- and
- a computer configured to perform operations comprising:
- receiving data comprising the resistivity values as the function of depth along the wellbore from the logging tool;
- identifying a plurality of porous zones from the wellbore based on petrophysical logs by characterizing each identified porous zone based on a porosity amount and a tolerable hole condition;
- converting the measured resistivity values to an amount of total dissolved solids for each of the plurality of porous zones;
- converting the amount of total dissolved solids to a pore fluid density;
- calculating a pressure based on the pore fluid density;
- and
- generating the pressure profile.
Dependencies are inferred from the claim text.