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

Other| February 01, 1997 Determination of the content and distribution of fixed ammonium in illite-smectite by X-ray diffraction: Application to North Sea illite-smectite Victor A. Drits; Victor A. Drits Russian Academy of Sciences, Institute of Geology, Moscow, Russian Federation Search for other works by this author on: GSW Google Scholar Holger Lindgreen; Holger Lindgreen Search for other works by this author on: GSW Google Scholar Alfred L. Salyn Alfred L. Salyn Search for other works by this author on: GSW Google Scholar American Mineralogist (1997) 82 (1-2): 79–87. https://doi.org/10.2138/am-1997-1-210 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Victor A. Drits, Holger Lindgreen, Alfred L. Salyn; Determination of the content and distribution of fixed ammonium in illite-smectite by X-ray diffraction: Application to North Sea illite-smectite. American Mineralogist 1997;; 82 (1-2): 79–87. doi: https://doi.org/10.2138/am-1997-1-210 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyAmerican Mineralogist Search Advanced Search Abstract A new X-ray diffraction method for the determination of the amount and distribution of fixed NH4+ in illite-smectite has been developed. Illite-smectite was saturated with K+ and heated at 150 °C. The 002 and 005 reflections were recorded with steps of 0.01° 2θ, and the experimental d values and the values for full-width at half-height (FWHH) were determined using a peak-profile–fitting procedure. Peak profiles were calculated with the NEWMOD program for illite structures having different amounts of NH4+ and different patterns for the distribution of NH4+ in interlayers. For Upper Jurassic illite-smectite from North Sea oil source rocks, the amount and the distribution of NH4+ in illite interlayers were determined by comparing the experimental values for d005 and FWHH with the values calculated for the selected illite structures. The amounts of NH4+ determined in this manner correlate well with the amounts determined by an isotopic dilution method. The results demonstrate 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 actually are tobelite layers. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.