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L.H. Adami

Publications and source records attributed to L.H. Adami.

4 recordsLinked to original sources
USGS1988

Experimental oxygen isotope fractionation between siderite-water and phosphoric acid liberated CO2-siderite

The equilibrium fractionation of O isotopes between synthetic siderite and water has been measured at temperatures ranging from 33° to 197°C. The fractionation between siderite and water over this temperature range can be represented by the equation: 10 3 ln α = 3.13 × 10 6 T −2 − 3.50. Comparison between the experimental and theoretical fractionations is favorable only at approximately 200°C; at lower temperatures, they generally differ by up to 2 permil. Siderite was prepared by the slow addition of ferrous chloride solutions to sodium bicarbonate solutions at the experimental temperatures. It was also used to determine the O isotope fractionation factors between phosphoric acid liberated CO 2 and siderite. The fractionation factors for this pair at 25° and 50°C are 1.01175 and 1.01075, respectively. Preliminary results of the measured C isotope fractionation between siderite and Co 2 also indicate C isotopic equilibrium during precipitation of siderite. The measured distribution of 13 C between siderite and CO 2 coincides with the theoretical values only at about 120°C. Experimental and theoretical C fractionations differ up to 3 permil at higher and lower temperatures.

Geochimica et Cosmochimica Acta↗
USGS1970

Water, hydrogen, deuterium, carbon, carbon-13, and oxygen-18 content of selected lunar material

The water content of the breccia is 150 to 455 ppm, with a δD from—580 to —870 per mil. Hydrogen gas content is 40 to 53 ppm with a δD of —830 to —970 per mil. The CO 2 is 290 to 418 ppm with δ 13 C = + 2.3 to + 5.1 per mil and δ 18 O = 14.2 to 19.1 per mil. Non-CO 2 carbon is 22 to 100 ppm, δ 13 C = —6.4 to —23.2 per mil. Lunar dust is 810 ppm H 2 O (D = 80 ppm) and 188 ppm total carbon(δ 13 C = —17.6 per mil). The 18 O analyses of whole rocks range from 5.8 to 6.2 per mil. The temperature of crystallization of type B rocks is 1100° to 1300°C, based on the oxygen isotope fractionation between coexisting plagioclase and ilmenite.

Science↗