Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-26T01:59:29.921Z Has data issue: false hasContentIssue false
  • English
  • Français

The effect of fluid/rock ratio on feldspar dissolution and illite formation under reservoir conditions

Published online by Cambridge University Press:  09 July 2018

W. L. Huang ,
A. M. Bishop  and
R. W. Brown
W. L. Huang
Affiliation:
Exxon Production Research Company, PO Box 2189, Houston, TX 77001, USA
A. M. Bishop
Affiliation:
Exxon Production Research Company, PO Box 2189, Houston, TX 77001, USA
R. W. Brown
Affiliation:
Exxon Production Research Company, PO Box 2189, Houston, TX 77001, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Experiments on the conversion of feldspar to illite reveal that variation of the fluid/rock ratio (flow rate) has a significant effect on the kinetics of feldspar dissolution and illite formation. Dissolution of albite in near-neutral KCl solution at 200°C and 500 bar shows that the Si and Na release rate per unit surface area of albite is faster with higher fluid/rock ratio. These results have application to the interpretation of secondary porosity formation. The experiments also reveal a special set of conditions under which rapid illite formation can occur. In contrast to the slow process of illite formation in neutral solution, there can be mass nucleation and growth of illite platelets on albite surfaces in an initially acidic solution with low fluid/rock ratio. In similar experiments with higher fluid/rock ratio, kaolinite forms instead of illite because there is insufficient solid to titrate the large volume of solution. This study suggests that illitization of feldspar or kaolinite may be triggered by a decreased rate of acidic fluid-influx during burial diagenesis.

Type
Research Article
Information
Clay Minerals , Volume 21 , Issue 4 , October 1986 , pp. 585 - 601
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1986

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

Aagard, P. & Helgeson, H.C. (1982) Thermodynamic and kinetic constraints on reaction rates among mineral and aqueous solutions. I. Theoretical considerations. Am. J. Sci. 282, 237–285.Google Scholar
Berner, R.A. & Holdren, G.R. (1979) Mechanism of feldspar weathering-—II. Observations of feldspar from soils. Geochim. Cosmochim. Acta 43, 1173–1186.CrossRefGoogle Scholar
Chou, L. & Wollast, R. (1984) Study of the weathering of albite at room temperature and pressure with a fluidized bed reactor. Geochim. Cosmochim Acta 48, 2205–2217.CrossRefGoogle Scholar
Fung, P.C., & Sanipelli, G.G. (1982) Surface studies of feldspar dissolution using surface replication combined with electron microscopic and spectroscopic techniques. Geochim Cosmochim. Acta 46, 503–512.Google Scholar
Garrels, R.M. & Howard, P. (1959) Reactions of feldspar and mica with water at low temperature and pressure. Clays Clay Miner. 6, 68–88.Google Scholar
Güven, N., Lafon, G.M. & Lee, L.J. (1982) Experimental alteration of albite to clays. Preliminary results. Proe. 7th Int. Clay Conf. Bologna and Pavia, 495–511.Google Scholar
Heald, M.T. & Larese, R.E. (1973) The significance of the solution of feldspar in porosity development. J. Sed. Petrology 43, 458–460.Google Scholar
Helgeson, H.C., Murphy, W.M. & Aagaard, P. (1984) Thermodynamic and kinetic constraints on reaction rates among minerals and aqueous solutions. II. Rate constants, effective surface area, and the hydrolysis of feldspar. Geochim Cosmochim Acta 8, 2405–2432.Google Scholar
Hemley, J.J. (1959) Some mineralogical equilibria in the system K2O-Al2O3-SiO2-H2O. Am. J. Sci. 257, 241–270.CrossRefGoogle Scholar
Holdren, G.R. & Adams, J.E. (1982) Parabolic dissolution kinetics of silicate minerals: an artifact of nonequilibrium precipitation processes?. Geology 10, 186–190.2.0.CO;2>CrossRefGoogle Scholar
Lagache, M. (1965) Contribution to the study of transformation of feldspar in water, between 100 and 200°C, under various CO2 pressures, and application to the synthesis of clay minerals. Soc. Franç Mineral. CristalL Bull. 88, 223–253.Google Scholar
Lindahl, P.C., Voight, K.C., Bishop, A.M., Lafon, G.M. & Huang, W.L. (1984) Determination of aluminium in hydrothermal reaction fluids by graphite furnace atomic absorption spectrophotometry. Atomic Spectroscopy. 5, 137–141.Google Scholar
Lundstrom, I. (1970) Etch pattern and albite twinning in two plagioclases. Arkiv Mineralogi och Geologi. 5, 63–91.Google Scholar
Petrovic, R., Berner, R.A. & Goldhaber, M.B. (1976) Rate control in dissolution of alkali feldspars. I. Study of residual feldspar grains in X-ray photoelectron spectroscopy. Geochim. Cosmochim. Acta. 40, 537–548.Google Scholar
Rossel, N.C. (1982) Clay mineral diagenesis in Rotliegend aeolian sandstones of the southern North Sea. Clay Miner. 17, 69–77.Google Scholar
Schmidt, V. & McDonald, D.A. (1979) The rate of secondary porosity in the course of sandstone diagenesis. Soc. Econ. Paleontologists and Mineralogists Spec. Publ. 26, 175–208.Google Scholar
Seemann, U. (1982) Depositional facies, diagenetic clay minerals and reservoir quality of Rotliegend sediments in the Southern Permian Basin (North Sea): Clay Miner. 17, 55–68.CrossRefGoogle Scholar
Surdam, R.C., Boese, S.W. & Crossey, L.J. (1984) The chemistry of secondary porosity. Pp. 127–149 in: Clastic Diagenesis (McDonald, D. A. and Surdam, R. C., editors), AAPG Memoir 37.Google Scholar
Stalder, P.J. (1973) Influence of crystallographic habit and aggregate structure of authigenic clay minerals on sandstone permeability. Geologie en Mijnbouw 5-214, 217–220.Google Scholar
Wellman, T.R. (1970) The stability of sodaiite in a synthetic syenite plus aqueous chloride fluid system: J. Petrology 11, 49–71.Google Scholar
Wolery, T.J. (1979) Calculation of chemical equilibrium between aqueous solution and minerals: the EQ3/6 software package. Lawrence Livermore Laboratory publication UCRL-52658.Google Scholar