GB1499427A - Three frequency modulated thermal neutron well logging - Google Patents

Three frequency modulated thermal neutron well logging

Info

Publication number
GB1499427A
GB1499427A GB2275875A GB2275875A GB1499427A GB 1499427 A GB1499427 A GB 1499427A GB 2275875 A GB2275875 A GB 2275875A GB 2275875 A GB2275875 A GB 2275875A GB 1499427 A GB1499427 A GB 1499427A
Authority
GB
United Kingdom
Prior art keywords
neutron
thermal
tangents
borehole
frequency modulated
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2275875A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Texaco Development Corp
Original Assignee
Texaco Development Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US489335A external-priority patent/US3930152A/en
Priority claimed from US05/489,330 external-priority patent/US3940613A/en
Priority claimed from US05/489,329 external-priority patent/US3940611A/en
Application filed by Texaco Development Corp filed Critical Texaco Development Corp
Publication of GB1499427A publication Critical patent/GB1499427A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V5/00—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity
    • G01V5/04—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity specially adapted for well-logging
    • G01V5/08—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity specially adapted for well-logging using primary nuclear radiation sources or X-rays
    • G01V5/10—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity specially adapted for well-logging using primary nuclear radiation sources or X-rays using neutron sources
    • G01V5/101—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity specially adapted for well-logging using primary nuclear radiation sources or X-rays using neutron sources and detecting the secondary Y-rays produced in the surrounding layers of the bore hole
    • G01V5/102—Prospecting or detecting by the use of ionising radiation, e.g. of natural or induced radioactivity specially adapted for well-logging using primary nuclear radiation sources or X-rays using neutron sources and detecting the secondary Y-rays produced in the surrounding layers of the bore hole the neutron source being of the pulsed type

Landscapes

  • Physics & Mathematics (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics (AREA)
  • Geophysics And Detection Of Objects (AREA)

Abstract

1499427 Neutron well-logging TEXACO DEVELOPMENT CORP 23 May 1975 [17 July 1974(3)] 22758/75 Heading G1A The disclosure and claims are broadly similar to those of Specification 1476676 (Div G1), with the modifications that a single thermal-neutron or gamma-ray detector is used, and that the substantially uninterrupted fast neutron flux irradiating the borehole and earth formations is harmonically and phase-coherently modulated with at least three modulation frequencies. In the embodiment a neutron source is modulated in a repetitive sequence of equal timeintervals at 400 Hz, 2000 Hz and 4000 Hz respectively. The tangents of the phase lags of the detected thermal-neutron population are computed, the three tangents being used in a set of simultaneous equations to extract the thermal-neutron decay constant of the earth formations surrounding the borehole.
GB2275875A 1974-07-17 1975-05-23 Three frequency modulated thermal neutron well logging Expired GB1499427A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US489335A US3930152A (en) 1974-07-17 1974-07-17 System for measuring earth formation thermal neutron lifetime utilizing a harmonically intensity modulated fast neutron source
US05/489,330 US3940613A (en) 1974-07-17 1974-07-17 Three frequency modulated thermal neutron lifetime log
US05/489,329 US3940611A (en) 1974-07-17 1974-07-17 Method for determining thermal neutron decay times of earth formations

Publications (1)

Publication Number Publication Date
GB1499427A true GB1499427A (en) 1978-02-01

Family

ID=27413842

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2275875A Expired GB1499427A (en) 1974-07-17 1975-05-23 Three frequency modulated thermal neutron well logging

Country Status (2)

Country Link
FR (1) FR2279119A1 (en)
GB (1) GB1499427A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3973131A (en) * 1974-12-26 1976-08-03 Texaco Inc. Pulsed neutron logging: multipurpose logging sonde for changing types of logs in the borehole without bringing the sonde to the surface

Also Published As

Publication number Publication date
FR2279119A1 (en) 1976-02-13
AU8272175A (en) 1977-01-06
FR2279119B1 (en) 1979-08-03

Similar Documents

Publication Publication Date Title
GB2108553B (en) Consolidation of geological formations of rock, earth, and coal
CA1010580A (en) Natural gamma radiation borehole logging system
CA997675A (en) Method of fracturing and repressuring subsurface geological formations employing liquified gas
ES455762A1 (en) Clay content determination by natural gamma ray spectrometry
AU511109B2 (en) Exploring geological formations
IE39859B1 (en) Method and apparatus for determining the potassium uranium and thorium contents of a geological formation
CA1004662A (en) Method for laser drilling subterranean earth formations
AU643983B2 (en) Method and apparatus for epithermal neutron porosity well logging
IE40854L (en) Well logging
CA2006638A1 (en) Pulsed neutron porosity logging
AU5859386A (en) Compensating for borehole effects in logging earth formations
GB2005395B (en) Cryostat for borehole sonde employing semiconductor detector
GB1499427A (en) Three frequency modulated thermal neutron well logging
DE3471764D1 (en) Epithermal neutron porosity measurement
Rasmussen Geology and mammalian paleontology of the Oligocene-Miocene Cabbage Patch formation, central-western Montana.
GB1366357A (en) Neutron measuring technique for investigating earth formations
MY7900003A (en) Method of consolidaating loose or incompetent subterranean formations
MY100409A (en) Method of using a borehole televiewer dipmeter for determining true dip azimuth.
AU8337475A (en) Process for the consilidation of geological formations and loosened rock and earth masses
ZA755691B (en) Water-insensitive system, in particular for sealing and consolidating waterbearing geological formations
GB1500350A (en) Three frequency modulated combination thermal neutron lifetime log and porosity log
AU511185B2 (en) Drilling deep boreholes in bedrock
CA1030276A (en) Method for determining thermal neutron decay times of earth formations
Price et al. Catalog of aquifer names and geologic unit codes used by the Water Resources Division
FR2251014A1 (en) Radioactive well logging - with comparison of neutron capture and aluminium isotope decay radiations

Legal Events

Date Code Title Description
PS Patent sealed