Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-23T12:01:44.967Z Has data issue: false hasContentIssue false

Tem Observations of Coherent Stacking Relations in Smectite, I/S and Illite of Shales: Evidence for MacEwan Crystallites and Dominance of 2M1 Polytypism

Published online by Cambridge University Press:  28 February 2024

Hailiang Dong
Affiliation:
Department of Geological Sciences, The University of Michigan, Ann Arbor, Michigan 48109-1063
Donald R. Peacor
Affiliation:
Department of Geological Sciences, The University of Michigan, Ann Arbor, Michigan 48109-1063
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

TEM characterization of stacking relations in I/S of expanded shale samples from the Gulf Coast and Michigan Basin was carried out to address the issues of the degree of coherency and the nature of layer stacking sequences in smectite, I/S and illite. The two-dimensional lattice fringe images obtained from this study show that cross fringes are commonly observed to be continuous over at least 3–4 layers for smectite, 6–7 layers for ordered I/S and 9–10 layers for illite-rich I/S. This demonstrates that such sequences are coherent, or at least semi-coherent (in smectite) units (MacEwan crystallites). The observations demonstrate that so-called fundamental particles are fragments of MacEwan crystallites formed primarily as a result of disaggregation along weakly-bonded smectite interlayers. However, both 0k1 and h01 reflections may coexist in selected area electron diffraction (SAED) patterns. The frequency of occurrence of the coexistence in SAED patterns decreases in the order smectite, I/S and illite for Gulf Coast samples. This is consistent with the presence of turbostratically-related interfaces in packets of all of these materials. Therefore, any given layer sequence in smectite, ordered I/S and illite may have both turbostratic and coherent interfaces. The proportion of coherently-related layers increases with increasing proportion of illite-like layers. The concept of fundamental or elementary particles is not related to layer sequences in non-disaggregated, original rocks. Indeed, it implies relations that are not valid.

The lattice fringe images, SAED and optical diffraction patterns demonstrate that where layers are coherently-related, 2M1 is the dominant polytypic sequence in all samples. However, this periodic 2M1 stacking is so frequently interrupted by stacking faults in smectite that it gives rise to apparent lMd polytypism. The degree to which the periodic 2M1 sequences are interrupted by stacking faults decreases with increasing proportion of illite-like layers. The SAED patterns of I/S and illite unmodified since its formation are diffuse parallel to c* and have poorly-defined, non-periodic reflections for indices k ≠ 3N as a measure of local ordering superimposed on poorly-ordered coherent sequences with a turbostratic component. X-ray diffraction (XRD) patterns, as integrated over domains with a range of heterogeneous stacking relations, do not represent simple mixtures of discrete IM and 2M1 polytypes.

The observations of this study imply that dissolution-crystallization is a dominant mechanism for the smectite-to-illite transition. The semi-coherent stacking of smectite-like layers in smectite-rich samples implies that either a dissolution-crystallization process took place subsequent to deposition of detrital smectite or that Gulf Coast smectite is an in-situ alteration product of volcanic ash.

Type
Research Article
Copyright
Copyright © 1996, The Clay Minerals Society

References

Ahn, J.H. and Buseck, P.R.. 1990. Layer-stacking sequences and structural disorder in mixed-layer illite/smectite: Image simulation and HRTEM imaging. Am Mineral 75: 267275.Google Scholar
Ahn, J.H. and Peacor, D.R.. 1986. Transmission and analytical electron microscopy of the smectite-to-illite transition. Clays & Clay Miner 34: 165179.Google Scholar
Ahn, J.H. and Peacor, D.R.. 1989. Illite/smectite from Gulf Coast shales: A reappraisal of transmission microscope images. Clays & Clay Miner 37: 542546.Google Scholar
Bailey, S.W.. 1988. X-ray diffraction identification of the polytypes of mica, serpentine, and chlorite. Clays & Clay Miner 36: 193213.CrossRefGoogle Scholar
Banfield, J.F., Jones, B.F. and Veblen, D.R.. 1991. An AEM-TEM study of weathering and diagenesis, Albert Lake, Oregon: II. Diagenetic modification of the sedimentary assemblage. Geochim Cosmochim Acta 55: 27952810.CrossRefGoogle Scholar
Baronnet, A., Nitsche, S. and Kang, Z.C.. 1993. Layer stacking microstructures in a biotite single crystal, a combined HRTEM-AEM study. Phase Transitions 43: 107128.CrossRefGoogle Scholar
Bayliss, P., Erd, D.C., Mrose, M.E., Sabina, A.P. and Smith, D.K.. 1986. Mineral Powder Diffraction File, Data book. p. 1396.Google Scholar
Buatier, M., Honnorez, J. and Ehret, G.. 1989. Fe-smectite-glauconite transition in hydrothermal green clays from the Galapagos spreading center. Clays & Clay Miner 37: 532541.CrossRefGoogle Scholar
Clauer, N., O'Neil, J.R., Bonnot-Courtois, C. and Holtzapffel, T.. 1990. Morphological, chemical, and isotopic evidence for an early diagenetic evolution of detrital smectite in marine sediments: Clays & Clay Miner 38: 3346.Google Scholar
Freed, R.L.. 1980. Shale mineralogy and burial diagnosis in four geopressured wells, Hidalgo and Brazoria Counties, Texas. In: Loucks, R.G., Richmann, D.L., Milliken, K.L., editors. Factors controlling reservoir quality in Tertiary sandstones and their significance to geopressured geothermal production. Division of Geothermal Energy, U.S. Department of Energy, Contract No. DOE/ET/27111-1, Appendix A: p. 111172.Google Scholar
Freed, R.L.. 1982. Clay mineralogy and depositional history of Frio Formation in two geopressured wells, Brazoria County, Texas. Gulf Coast Association of Geological Societies Transactions 32: 459463.Google Scholar
Freed, R.L. and Peacor, D.R.. 1989a. Geopressured shale and sealing effect of smectite to illite transition. Am Assoc Petro Geol Bull 73: 12231232.Google Scholar
Freed, R.L. and Peacor, D.R.. 1989b. TEM lattice fringe images with R1 ordering of illite/smectite in Gulf Coast pelitic rocks (abstract). G S A Abs with Prog 21: A16.Google Scholar
Freed, R.L. and Peacor, D.R.. 1992. Diagenesis and the formation of authigenic illite-rich I/S crystals in Gulf Coast shales: TEM study of clay separates. J Sed Pett 62: No. 2, 220234.Google Scholar
Grubb, S.M.B., Peacor, D.R. and Jiang, W.-T.. 1991. Transmission electron microscope observations of illite polytypism. Clays & Clay Miner 39: 540550.CrossRefGoogle Scholar
Guthrie, G.D. Jr. 1995. Personal communication. Geology and Geochemistry Group. EE S-1. Los Alamos National Laboratory. Los Alamos. NM87545.Google Scholar
Guthrie, G.D. Jr. and Veblen, D.R.. 1989a. High-resolution transmission electron microscopy of mixed-layer illite/smectite: Computer simulations. Clays & Clay Miner 37: 111.CrossRefGoogle Scholar
Guthrie, G.D. Jr. and Veblen, D.R.. 1989b. High-resolution transmission electron microscopy applied to clay minerals. In: Coyne, L.M., McKeever, S.W.S., Blake, D.F., editors. Spectroscopic characterization of minerals and their surfaces. Sym. Ser. 415. Washington, D.C. Am Chem Soc. p. 7593.Google Scholar
Guthrie, G.D. Jr. and Veblen, D.R.. 1990. Interpreting one-dimensional high-resolution transmission electron micrographs of sheet silicates by computer simulation. Amer. Mineral 75: 276288.Google Scholar
Hoffmann, J. and Hower, J.. 1979. Clay mineral assemblages as low grade metamorphic geothermometers: Application to the thrust faulted Disturbed Belt of Montana, U.S.A. Society of Economic Paleontologists and Mineralogists Special Publications 26: 5579.Google Scholar
Hover, C.H., Peacor, D.R. and Walter, L.M.. Personal Communication. 1995. Department of Geological Sciences. The University of Michigan. Ann Arbor, MI 48109–1063.Google Scholar
Hower, J., Eslinger, E.V., Hower, M.E. and Perry, E.A.. 1976. Mechanism of burial metamorphism of argillaceous sediments: Mineralogical and chemical evidence. G.S.A. Bull. 87: 725737.Google Scholar
Jiang, W.-T., Peacor, D.R., Merriman, R.J. and Roberts, B.. 1990. Transmission and analytical electron microscopic study of mixed-layer illite-smectite formed as an apparent replacement product of diagenetic illite. Clays & Clay Miner 38: 449468.CrossRefGoogle Scholar
Jiang, W.-T. and Peacor, D.R.. 1991. Transmission electron microscopic study of the kaolinitization of muscovite. Clays & Clay Miner 39: 113.CrossRefGoogle Scholar
Kim, J.W., Peacor, D.R., Tessier, D. and Elsass, F.. 1995. A technique for permanent expansion of smectite interlayers for TEM observation: The magic bullet that retains texture. Clays & Clay Miner 43: 5157.CrossRefGoogle Scholar
Lee, J.H.K., Peacor, D.R., Lewis, D.D. and Wintsch, R.P.. 1985. Chlorite-illite/muscovite interlayered and interstratified crystals: A TEM/STEM study. Contrib Mineral Petrol 88: 372385.CrossRefGoogle Scholar
Lindgreen, H. and Hansen, P.L.. 1991. Ordering of illite-smectite in upper Jurassic claystones from the North Sea. Clay Miner 26: 105125.CrossRefGoogle Scholar
Maxwell, D.T. and Hower, J.. 1967. High grade diagenesis and low-grade metamorphism of illite in the Precambrian Belt series. Am Mineral 52: 843857.Google Scholar
Nadeau, P.H.. 1985. The physical dimensions of fundamental clay particles: Clay Miner 20: 499514.Google Scholar
Nadeau, P.H., Tait, J.M., McHardy, W.J. and Wilson, M.J.. 1984a. Interstratified XRD characteristics of physical mixtures of elementary clay particles. Clay Miner 19: 6776.CrossRefGoogle Scholar
Nadeau, P.H., Wilson, M.J., McHardy, W.J. and Tait, J.M.. 1984b. Interstratified clays as fundamental particles. Science 225: 923925.CrossRefGoogle ScholarPubMed
Nadeau, P.H., Wilson, M.J., McHardy, W.J. and Tait, J.M.. 1984c. Interparticle diffraction: A new concept for interstratified clays. Clay Miner 19: 757769.CrossRefGoogle Scholar
Nadeau, P.H., Wilson, M.J., McHardy, W.J. and Tait, J.M.. 1985. The conversion of smectite to illite during diagenesis: Evidence from some illitic clays from bentonites and sandstones. Mineral Mag 49: 393400.CrossRefGoogle Scholar
Peacor, D.R.. 1992. Diagenesis and low-grade metamorphism of shales and slates. In: Buseck, P., Ribbe, P.H., editors. Reviews in Mineralogy, v. 27, Minerals and Reactions in Atomic Scale: Transmission Electron Microscopy. Chelsea Mineralogical Society of America. p. 335380.Google Scholar
Reynolds, R.C. Jr. 1992. X-ray diffraction studies of illite/smectite from rocks, <lμm randomly oriented powders, and <1μm oriented powder aggregates: The absence of laboratory-induced artifacts. Clays & Clay Miner 40: 387396.CrossRefGoogle Scholar
Reynolds, R.C. Jr. 1995. Personal communication. Department of Earth Sciences. Dartmouth College. Hanover, NH 03755.Google Scholar
Smith, J.V. and Yoder, H.S.. 1956. Experimental and theoretical study of the mica polymorphs. Mineral Mag 31: 209231.Google Scholar
Srodon, J., Andreoli, C., Elsass, F. and Robert, M.. 1990. Direct high-resolution transmission electron microscopic measurement of expandability of mixed-layer illite/smectite in bentonite rock. Clays & Clay Miner 38: 373379.CrossRefGoogle Scholar
Tessier, D.. 1984. Etude expérimental de l'organisation des matériaux argileux [Dr. Science thesis]. Univ. Paris VII, INRA publ. 361p.Google Scholar
Vali, H., Hesse, R. and Martin, R.F.. 1994. A TEM-based definition of 2: 1 layer silicates and their interstratified constitutes. Am Mineralog, 79: 644653.Google Scholar
Veblen, D.R., Guthrie, G.D. Jr., Livi, K.J.T. and Reynolds, R.C. Jr. 1990. High-resolution transmission electron microscopy and electron diffraction of mixed-layer illite/smectite: Experimental results. Clays & Clay Miner 38: 113.CrossRefGoogle Scholar
Velde, B. and Hower, J.. 1963. Petrological significance of illite polytypism in Paleocene sedimentary rocks. Am Mineral 48: 12391254.Google Scholar
Yau, Y.-C., Peacor, D.R. and McDowell, S.D.. 1987. Smectite-to-illite reaction in Salton Sea shales: A transmission and analytical electron microscopy study. J Sed Pet 57: 335342.Google Scholar
Yoder, H.S. and Eugster, H.P.. 1955. Synthetic and natural muscovites. Geochim Cosmochim Acta 6: 157185.CrossRefGoogle Scholar