The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 02, 1994
Filed:
Jun. 14, 1991
Charles Case, West Redding, CT (US);
Charles Watson, Danbury, CT (US);
Richard Lawrence, Stormville, NY (US);
Schlumberger Technology Corporation, New York, NY (US);
Abstract
A new technique, called the sensitivity function technique, has been developed for modeling nuclear density tools. Specifically, sensitivity functions relate a change in formation properties to a change in detector response and are based on the first order perturbation expansion of the radiation transport equation. The sensitivity function is a quasi-linear model which works extremely well over a wide range of mudcake and formation conditions, as shown by extensive benchmark comparisons against actual tool measurements. The detector responses are calculated by a convolution of density sensitivity functions, calculated in a separate set of Monte Carlo computer runs, with the formation properties and is extremely fast. Because this technique is both fast and accurate, it represents a significant advance in the ability to model gamma-gamma density tools and will allow the use of fast forward modeling to improve the log interpretation process.