Results 171 to 180 of about 688 (199)

Secondary Porosity in Laumontite-Bearing Sandstones: ABSTRACT

AAPG Bulletin, 1982
Some sedimentary rocks, particularly those containing volcanogenic material, develop laumontite cements during burial with increasing temperature. The development of laumontite cements in sandstones is highly destructive to reservoir potential. As a result, in the search for hydrocarbons, laumontite-bearing sedimentary rocks commonly are considered ...
Ronald B. Frost, Ronald C. Surdam, Laura J. Crossey*   +2 more
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Study relating to temperature stability of the Natural Laumontite Zeolite

Crystal Research and Technology, 1984
AbstractOn the basis of the DTA measurements, the natural laumontite zeolite has been subjected to thermal decomposition at temperatures of 20, 250, 420, 580, 750, and 1000°C. The decomposition products were identified by the X‐ray powder method (CuKα‐) and IR spectroscopy (Nujol).
D. Rykl, F. Pechar
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Partial dehydration of laumontite: thermodynamic constraints and petrogenetic implications

Mineralogical Magazine, 2001
AbstractLaumontite is a common zeolite mineral indicative of low-grade metamorphism of lavas and volcaniclastic sediments. Stoichiometric laumontite (CaAl2Si4O12·4.5H2O) dehydrates in air at 298.15 K, 1 bar to leonhardite (CaAl2Si4O12·3.5H2O) via loss of water from the W1 crystallographic site.
P. S. Neuhoff, D. K. Bird
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Retention of uranium(VI) by laumontite, a fracture-filling material of granite

Journal of Radioanalytical and Nuclear Chemistry, 2009
Retention of U(VI) by laumontite, a fracture-filling material of granite was investigated by conducting dynamic and batch sorption experiments in a glove-box using a granite core with a natural fracture. The hydrodynamic properties of the granite core were obtained from the elution curve of a non-sorbing tracer, Br−. The elution curve of U(VI) showed a
M. H. Baik, S. Y. Lee, W. J. Shon
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LAUMONTITE DI MARCIANA (ISOLA D'ELBA)

, 1966
M. DE FINO, MENCHETTI, SILVIO
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Guest-guest interaction and phase transitions in the natural zeolite laumontite

Journal of Inclusion Phenomena and Molecular Recognition in Chemistry, 1995
The zeolite water arrangement in laumontite Ca3.85Na0.23K0.06Al7.96Si16.03O48·nH2O (n=16–18) and leonhardite (n=12–14.4) has been studied from1H and27Al-NMR data at temperatures of 200–390 K. Close agreement is found between NMR data obtained for samplesn=12 andn=18 and previous X-ray and neutron diffraction data.
S. P. Gabuda, S. G. Kozlova
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Die R�ntgenkristallographie von Laumontit von Stainz (Steiermark)

Tschermaks Mineralogische und Petrographische Mitteilungen, 1956
Die rontgenographisch bestimmten Daten an einem bergfrischen Laumontit mit etwas mehr als drei Molekulen H2O pro Formeleinheit sind a0=14·67±0·15 A, b0=13·12±0·07 A, c0=7·52±0·10 A, β=111°36′. Das Diffraktionssymbol ist 1 2/m 1 C ... mit den moglichen Raumgruppen C 2-C23 Cm-Cs3 und C 2/m-C2h3.
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Burial Thermal Histories, Vitrinite Reflectance, and Laumontite Isograd: ABSTRACT

AAPG Bulletin, 1985
The optical reflectance of vitrinite has become the standard basis for quantitative judgments of integrated temperature-time (burial) histories. Inferences about the crystallization temperature of the calcium zeolite laumontite also have been used repeatedly for such purposes.
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Pressure‐Induced Hydration Effects in the Zeolite Laumontite

Angewandte Chemie International Edition, 2004
Catherine L I M, White, A Rabdel, Ruiz-Salvador, Dewi W, Lewis   +2 more
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laumontite, n.

2023
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