Determination of the content and distribution of fixed ammonium in illite-smectite by X-ray diffraction; application to North Sea illite-smectite

A new XRD method for the determination of the amount and distribution of fixed NH + 4 in illite-smectite is described. The sample is saturated with K+ and heated at 150°C, and the 002 and 005 reflections recorded using a peak-profile-fitting procedure. For Upper Jurassic illite-smectite from North S...

Full description

Saved in:
Bibliographic Details
Published in:The American mineralogist 1997-02, Vol.82 (1-2), p.79-87
Main Authors: Drits, Victor A, Lindgreen, Holger, Salyn, Alfred L
Format: Article
Language:English
Subjects:
Ammonium
ammonium ion
Atlantic Ocean
clastic rocks
clay minerals
Illite
ion exchange
Jurassic
Mesozoic
Mineralogy
Minerals
North Atlantic
North Sea
sedimentary rocks
shale
sheet silicates
silicates
smectite
Upper Jurassic
X-ray diffraction
X-ray diffraction data
X-rays
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A new XRD method for the determination of the amount and distribution of fixed NH + 4 in illite-smectite is described. The sample is saturated with K+ and heated at 150°C, and the 002 and 005 reflections recorded using a peak-profile-fitting procedure. For Upper Jurassic illite-smectite from North Sea oil source rocks, the NH + 4 in illite interlayers was determined by comparing the experimental values for d005 (full-width at half-height) with the values calculated for the selected illite structures. Results show that these illite-smectite samples have K end-member illite and NH4 end-member illite (tobelite) layers and that the illite layers formed during diagenesis and oil generation are actually tobelite.
ISSN:0003-004X
1945-3027
DOI:10.2138/am-1997-1-210