Authigenic Clay Minerals in the Rustler Formation, WIPP Site Area, New Mexico

Abstract

Transuranic waste is planned for disposal in the Late Permian evaporites of the Delaware Basin, southeastern New Mexico, at the WIPP Site. The disposal horizon is located in the bedded halite of the Salado Formation, which is overlain by the impure halite-anhydrite (gypsum)-siltstone-mudstone of the Rustler Formation. The Rustler Formation also contains two dolomite members, the Magenta and Culebra, which transmit water. The Culebra Member is suspected to have actively interacted with waters at time(s) from the Late Permian to the present, and it is important to assess the reactivity of these waters in conjunction with WIPP stability.

We have investigated the Rb-Sr systematics of clay minerals from the Culebra Member and elsewhere in the Rustler Formation. By separating the less than 0.125 µm size material we are able to deal with presumed true authigenic clay minerals. The authigenic fraction is especially sensitive to chemical and isotopic exchange with waters, and an episodic exposure to a large amount of water will re-set the clay minerals to such a time. Our data yield 259 ± 22 Ma Rb-Sr isochron, which is consistent with the Late Permian age of the Rustler Formation. This age demonstrates that age-determining cations in these clay minerals have preserved their isotopic and chemical integrity since the Late Permian.

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References

  1. 1.

    D.W. Powers, S.J. Lambert, S.E. Shaffer, L.R. Hill, and W.D. Weart, Eds. SAND 78–1596, 1979.

  2. 2.

    U.S. Dept. Energy, Final Environmental Impact Statement, Waste Isolation Pilot Plant, 1980.

  3. 3.

    D.G. Brookins and S.J. Lambert, Sci. Basis Nuc. Waste Mnt. X, J.K. Bates and W.B. Seefeldt, Eds., (Elsevier Sci. Pub. Co. 1987), p. 502.

  4. 4.

    D.G. Brookins and S.J. Lambert, Sci. Basis Nuc. Waste Mnt. XI, M.J. Apted and R.E. Westerman, Eds., (Elsevier Sci. Pub. Co. 1988), p. 255.

  5. 5.

    J.K. Register, Unpub. M.S. Thesis, Univ. New Mexico (1979).

  6. 6.

    M.E. Ostrom, J. Sed. Pet., 31 (1961) 123.

    CAS  Google Scholar 

  7. 7.

    P.L. Hauff, USGS OFR 82–934.

  8. 8.

    D.G. Brookins, U.S. Dept. Energy Rpt. 76-029E, GJO (1979).

  9. 9.

    D. York, Earth Plan. Sci. Lttrs., 5 (1969) 320.

  10. 10.

    D.G. Brookins, N.M. Bur. Mns. Min. Res. Spec. Pub. 10 (1981), 147.

  11. 11.

    J.P. Morton, Unpub. Ph.D. Dissertation, Univ. Texas, Austin (1983).

  12. 12.

    J.K. Register, D.G. Brookins, M.E. Register, and S.J. Lambert, in Sci. Basis Nuc. Waste Mnt. II, ed., C.J. Northrop (Plenum Press, NY 1980), 445.

  13. 13.

    D.G. Brookins, J.K. Register, M.E. Register, and S.J. Lambert, in Sci. Basis Nuc. Waste Mnt. II, ed., C.J. Northrop (Plenum Press, NY, 1980), 479.

  14. 14.

    S.J. Lambert and D.M. Harvey, SAND87-0138, 1987.

  15. 15.

    Faure, G., Principles of Isotope Geology, 2d Ed (Wiley-Interscience, NY, 1987), 589.

  16. 16.

    Brookins, D.G., Chem. Geol. 69, (1988), 209.

    CAS  Article  Google Scholar 

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Brookins, D.G., Lambert, S.J. & Ward, D.B. Authigenic Clay Minerals in the Rustler Formation, WIPP Site Area, New Mexico. MRS Online Proceedings Library 176, 665 (1989). https://doi.org/10.1557/PROC-176-665

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