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J.R. Lindsay

Publications and source records attributed to J.R. Lindsay.

6 recordsLinked to original sources

MAGMIX: a basic program to calculate viscosities of interacting magmas of differing composition, temperature, and water content

MAGMIX is a BASIC program designed to predict viscosities at thermal equilibrium of interacting magmas of differing compositions, initial temperatures, crystallinities, crystal sizes, and water content for any mixing proportion between end members. From the viscosities of the end members at thermal equilibrium, it is possible to predict the styles of magma interaction expected for different initial conditions. The program is designed for modeling the type of magma interaction between hypersthenenormative magmas at upper crustal conditions. Utilization of the program to model magma interaction at pressures higher than 200 MPa would require modification of the program to account for the effects of pressure on heat of fusion and magma density. ?? 1988.

Computers & Geosciences↗

Semimicro chemical and x-ray fluorescence analysis of lunar samples

Major and selected minor elements were determined in seven whole rock fragments, five portions of pulverized lunar rock, and the lunar soil. Three different rock types were represented: vesicular, fine-grained basaltic rocks; medium- to coarse-grained, vuggy gabbroic rocks; and breccia. The ranges (in percent) for the major constituents of the lunar samples are: SiO 2 , 38 to 42; Al 2 O 3 , 8 to 14; total iron as FeO, 15 to 20; MgO, 6 to 8; CaO, 10 to 12; Na 2 O, 0.5 to 1; K 2 O, 0.05 to 0.4; TiO 2 , 8 to 13; MnO, 0.2 to 0.3; and Cr 2 O 3 , 0.2 to 0.4. The high reducing capacity of the samples strongly suggests the presence of Ti(III).

Science↗