Formation fluid evaluation

摘要

In-situ formation fluid evaluation methods and apparatus configured to measure a first resonance frequency of a first fluid using a first densimeter downhole, wherein a first density of the first fluid is known; measure a second resonance frequency of a second fluid using a second densimeter downhole, wherein the second fluid is a formation fluid received by the second densimeter downhole, and wherein a second density of the second fluid is unknown; and determine the second density of the second fluid using the first and second resonance frequencies and the known first density.

主权项

1. A method of in-situ formation fluid evaluation, comprising:
measuring a first resonance frequency of a first fluid using a first densimeter downhole, wherein a first density of the first fluid is known; measuring a second resonance frequency of a second fluid using a second densimeter downhole, wherein the second fluid is a formation fluid received by the second densimeter downhole, and wherein a second density of the second fluid is unknown; determining a viscosity of the second fluid; determining the second density of the second fluid using the first and second resonance frequencies and the known first density; and iteratively determining a viscosity and the second density of the second fluid until a variation of the determined viscosity and the second density is less than an estimated uncertainty.