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G.A. Sellers

Publications and source records attributed to G.A. Sellers.

2 recordsLinked to original sources

Application of laser microprobe (LAMMA 1000) to "fingerprinting" of coal constituents in bituminous coal

A laser microprobe (LAMMA-1000) microchemical analysis of vitrinites of different morphologies but similar reflectances within the same bituminous coal bed indicates distinct “fingerprint” spectra. The banded form of vitrinite contains Li, Ti, Ba, Sr, F, and Cl which were not detected in the nonbanded vitrinite. These differences may indicate a different plant source or the introduction of these elements from fluids mobilized during diagenesis. The nonbanded vitrinite (called corpocollinite), which was contained in a pyrite coal-ball seed fern permineralization of Myeloxylon , may have been protected from influx of these elements due to entrapment by pyrite during an early peat stage. An ion at M/Z 65, which is characteristic of the banded vitrinite, may indicate C 5 H 5 + and, perhaps a difference in the chemical structure of the two vitrinites. These results demonstrate that “fingerprint” spectra can be obtained from vitrinite macerals by LAMMA and that these “fingerprints” have genetic implications.

International Journal of Coal Geology

Lunar soil: Size distribution and mineralogical constituents

The lunar soil collected by Apollo 11 consists primarily of submillimeter material and is finer in grain size than soil previously recorded photographically by Surveyor experiments. The main constituents are fine-grained to glassy rocks of basaltic affinity and coherent breccia of undetermined origin. Dark glass, containing abundant nickel-iron spheres, coats many rocks, mineral, and breccia fragments. Several types of homogeneous glass occur as fragments and spheres. Colorless spheres, probably an exotic component, are abundant in the fraction finer than 20 microns.

Science