Hostname: page-component-848d4c4894-2pzkn Total loading time: 0 Render date: 2024-05-17T16:18:22.469Z Has data issue: false hasContentIssue false

Natural Ammonium Illites from Black Shales Hosting a Stratiform Base Metal Deposit, Delong Mountains, Northern Alaska

Published online by Cambridge University Press:  02 April 2024

Edward J. Sterne*
Affiliation:
Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755
Robert C. Reynolds Jr.
Affiliation:
Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755
Half Zantop
Affiliation:
Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755
*
1Present address: Amoco Production Company (USA), Amoco Building, 1670 Broadway, Denver, Colorado 80202.

Abstract

Naturally occurring ammonium illites have been discovered in black shales surrounding a stratiform base metal deposit in the DeLong Mountains, northern Alaska. Infrared spectra of the samples exhibit pronounced absorption at 1430 cm−1, the resonant-banding frequency for NH4+ coordinated in the illite interlayer. X-ray powder diffraction characteristics of the ammonium illites include an expanded d(001) spacing, with values as large as 10.16 Å, and ratios for I001/I003 and I002/I005 of about 2. Infrared analyses of physical mixtures of NH4Cl with a standard illite, and comparisons with synthetic ammonium micas indicate significant substitution (>50%) of NH4+ for K+ in the illite interlayer position. Nitrogen determinations on two ammonium illites after removal of carbonaceous matter gave values of 1.48 wt. % NH4+ and 1.44 wt. % NH4+. A survey of more than 150 different shale horizons indicates that the NH4+ content of the illites increases in proximity to the stratiform base metal mineralization.

Резюме

Резюме

Натурально выступающие аммониевые иллиты были открыты в черных сланцеватых глинах, окружающих основной металлический осадок в горах ДеЛонга в северной Аласке. Инфракрасные спектры образцов указывают на значительную абсорбцию при 1430 см−1, частоте резонансной полосы NH4+, координированного в иллитовой прослойке. Характеристики рентгеновской порошковой дифракции аммониевых иллитов включают увеличенное расстояние d(001), co значениями, достигающими 10,16 Å а также отношениями I001/I003 и I002/I005 порядка 2. Инфракрасные анализы физических смесей NH4Cl со стандартным иллитом и сравнения с синтетическими аммониевыми слюдами указывают на значительную подстановку (>50%) иона NH4+ вместо иона K+ в межслойной области иллита. Определение количества азота в двух аммониевых иллитах после удаления углистой среды привело к величинам 1,48% веса NH4+ и 1,44% веса NH4+. Исследование более, чем 150 различных ярусов сланцевых глин показывает, что количество NH4+ в иллитах увеличивается в поблизости основной металлической минерализации. [E.C.]

Resümee

Resümee

Natürlich auftretende Ammonium-Illite wurden in den Schwarzschiefern gefunden, die eine schichtförmige Erzlagerstätte in den Delong Mountains, Nord Alaska, umgeben. Die Infrarotspektren der Proben zeigen eine deutliche Absorption bei 1430 cm−1, d.h. die Resonanzfrequenz von NH4+, das in die Illitzwischenschicht eingebaut ist. Die Röntgenpulverdiffraktometerdiagramme der Ammonium-Illite zeigen einen aufgeweiteten d(001) Abstand, mit Werten um 10,16 Å und I001/I003 bzw. I002/I005 Verhältnissen von etwa 2. Infrarotuntersuchungen an mechanischen Gemengen aus NH4Cl und einem Standard Illit und Vergleiche mit synthetischen Ammonium-Glimmern deuten auf eine beträchtliche Substitution (>50%) von NH4+ für K+ auf den Zwischenschichtplätzen des Illit hin. Stickstoffbestimmungen an zwei Ammonium-Illiten nach der Entfernung von kohlenstoffhaltigen Substanzen ergaben Werte von 1,48 Gew.-% NH4+ bzw. 1,44 Gew.-% NH4+. Untersuchungen von mehr als 150 verschiedenen Schieferhorizonten deuten darauf hin, daß der NH4+-Gehalt der Illite mit zunehmender Nähe an die Metall-Mineralisation ansteigt. [U.W.]

Résumé

Résumé

Des illites ammonium de provenance naturelle ont été découvertes dans des argilites noires entourant un dépôt stratiforme d'un métal de base dans les montagnes DeLong en Alaska du nord. Des spectres infrarouges des échantillons exhibent une adsorption prononcée à 1430 cm−1, la fréquence des liaisons resonantes pour NH4+ coordonné dans l'intercouche de l'illite. Les caractéristiques de diffraction poudrée aux rayons-X des illites ammonium comprennent un espacement d(001) élargi, avec des valeurs atteignant 10,16 Å, et des proportions pour I001/I003 et I002/I005 d’à peu près 2. Des analyses infrarouges de mélanges physiques de NH4Cl avec une illite standard, et des comparaisons avec des micas ammonium synthétiques indiquent une substitution significative (>50%) de NH4+ pour K+ dans la position intercouche illite. Des déterminations nitrogène sur deux illites ammonium après l'enlèvement de matière carbonacée ont donné des valeurs de 1,48 wt. % NH4+ et 1,44 wt. % NH4+. Un relevé de plus de 150 horizons argilite différents a indiqué que le contenu en NH4+ des illites accroit à proximité de la minéralisation stratiforme du métal de base.

Type
Research Article
Copyright
Copyright © 1982, The Clay Minerals Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Anderson, J. U., 1963 An improved pretreatment for min-eralogical analysis of samples containing organic matter Clays & Clay Minerals 10 380388.Google Scholar
Barker, D. S., 1964 Ammonium in alkali feldspars Amer. Mineral. 48 851858.Google Scholar
Barrer, R. M. and Denny, P. J., 1961 Hydrothermal chemistry of the silicates. Part IX. Nitrogenous aluminosilicates J. Chem. Soc. Part 1 9711000.CrossRefGoogle Scholar
Churkin, M. Jr., Nokleberg, W. J. and Huie, C., 1979 Collision-deformed Paleozoic continental margin, western Brooks Range, Alaska Geology 7 379383.2.0.CO;2>CrossRefGoogle Scholar
Erd, R. C., White, D. E., Fahey, J. J. and Lee, D. E., 1964 Buddingtonite, an ammonium feldspar with zeolitic water Amer. Mineral. 49 831850.Google Scholar
Eugster, H. P. and Munoz, J., 1966 Ammonium micas: possible sources of atmospheric ammonia and nitrogen Science 151 683686.CrossRefGoogle ScholarPubMed
Farmer, V. C. and Farmer, V. C., 1974 The Layer Silicates The Infrared Spectra of Minerals ed. London Mineralogical Society 331363.CrossRefGoogle Scholar
Gruner, J. W., 1939 Ammonium mica synthesized from ver-miculite Amer. Mineral. 24 428433.Google Scholar
Higashi, S., 1978 Dioctahedral mica minerals with ammonium ions Mineral. J. 9 1627.CrossRefGoogle Scholar
Hower, J. and Mowatt, T. C., 1966 The mineralogy of illites and mixed-layer illite/montmorillonites Amer. Mineral. 51 825854.Google Scholar
Karyakin, A. V., Volynets, V. F. and Kriventsova, G. A., 1973 Investigation of nitrogen compounds in micas by infrared spectroscopy Geochem. Int. 10 326329.Google Scholar
Muller, P. J., 1977 C/N ratios in Pacific deep-sea sediments: Effect of inorganic ammonium and organic nitrogen compounds sorbed by clays Geochim. Cosmochim. Acta 41 765776.CrossRefGoogle Scholar
Nokleberg, W. J. and Winkler, G. R., 1978 Geologic setting of the lead and zinc deposits, Drench water Creek area, Howard Pass Quadrangle, western Brooks Range, Alaska U.S. Geol Surv. Open-File Rept. .CrossRefGoogle Scholar
Plahuta, J. T. and Robinson, J. D., 1979 Zinc-lead-barite mineralization in upper Paleozoic marine sedimentary rocks at the Red Dog deposit, DeLong Mountains, Alaska Proc. 84th Annual Congress, Northwest Mining Assoc. .Google Scholar
Reynolds, R. C. Jr., Brindley, G. W. and Brown, G., 1980 Interstratified clay minerals Crystal Structures of Clay Minerals and Their X-Ray Identification eds. London Mineralog-ical Society 249303.CrossRefGoogle Scholar
Sterne, E. J., 1981 Clay mineralogy and carbon-nitrogen geochemistry of the Lik and Competition Creek stratiform Zn-Pb-Ag base metal deposits, DeLong Mountains, northern Alaska .Google Scholar
Van der Marel, H. W., 1966 Quantitative analysis of clay minerals and their admixtures Contrib. Miner. Petrol. 12 7382.Google Scholar
Vedder, W., 1965 Ammonium in muscovite Geochim. Cosmochim. Acta 29 221228.CrossRefGoogle Scholar
Wlotzka, F. and Wedepohl, K. H., 1972 Nitrogen: Abundance in rock-forming minerals Handbook of Geochemistry ed. Berlin, Heidelberg, New York Springer-Verlag 7D17L3.Google Scholar
Yamamoto, T. and Nakahira, M., 1966 Ammonium ions in sericites Amer. Mineral. 51 17751778.Google Scholar