Methods and apparatus for characterization of petroleum fluids contaminated with drilling mud

A system for characterizing formation fluid in an earth formation surrounding a borehole drilled into the earth formation, the system comprising:

• a borehole tool positionable at different locations in the borehole, the borehole tool including a fluid sampling device for sampling formation fluid at a given location by drawing formation fluid into a flowline disposed therein, and a fluid analyzer for analyzing the formation fluid in the flowline to derive first data characterizing properties of the formation fluid in the flowline, the first data including data representing temperature and pressure of the formation fluid in the flowline, wherein the formation fluid comprises fluid contaminated with mud filtrate;
• a data processing system operably coupled to the fluid analyzer, the data processing system adapted to derive second data and third data characterizing a plurality of properties of the formation fluid at the temperature and pressure of the formation fluid in the flowline, wherein the second data is based on the first data and the second data characterizes properties of the formation fluid that include effects from contamination of the mud filtrate in the formation fluid, and wherein the third data is based on the second data and the third data characterizes properties of the formation fluid where the effects from contamination of the mud filtrate in the formation fluid have been removed;
• and
• wherein the first data, second data, and third data are derived without employing analysis of formation fluid from another location within the borehole.

An apparatus for use in a system for characterizing formation fluid in an earth formation surrounding a borehole drilled into the earth formation, the system including a borehole tool positionable at different locations in the borehole, the borehole tool including a fluid sampling device for sampling formation fluid at a given location by drawing formation fluid into a flowline disposed therein, and a fluid analyzer for analyzing the formation fluid in the flowline to derive first data characterizing properties of the formation fluid in the flowline, the first data including data representing temperature and pressure of the formation fluid in the flowline, the apparatus comprising a data processing system operably coupled to the fluid analyzer, the data processing system adapted to derive second data and third data characterizing a plurality of properties of the formation fluid at the temperature and pressure of the formation fluid in the flowline, wherein the second data is based on the first data and the second data characterizes properties of the formation fluid that include effects from contamination of mud filtrate in the formation fluid, wherein the third data is based on the second data and the third data characterizes properties of the formation fluid where the effects from contamination of the mud filtrate in the formation fluid have been removed, and wherein the second data, and third data are derived without sampling and analysis of formation fluid at another location within the borehole.