Patent · US Expired

System and methods for NMR signal processing without phase alternated pair stacking

US6525534B2 · kind B2 · utility

19Cited by
49References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 15, 2001
Grant dateFeb 25, 2003
Priority date
Expiry dateJun 15, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/5617
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A system and methods for improving the vertical resolution of NMR logs based on data acquisition methods and signal processing techniques that need not apply Phase Alternated Pair Stacking (PAPS). The method is based on reducing the level of coherent non-formation signals, by estimating these signals and removing the estimates from the underlying NMR pulse echo trains. Once the estimated non-formation signal components have been removed, standard NMR processing methods are applied to derive petrophysical properties of the formation being investigated. In a preferred embodiment the NOPAPS method of this invention is practiced along with a data acquisition sequence, which can be used to further increase the logging speed of the tool or vertical resolution of the measurements.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.