Geochemical Variation of Inorganic Constitutents in a North Dakota Lignite

摘要

This paper summarizes information on the distribution of major and trace elements in a stratigraphic sequence of sedimentary materials in a major lignite-producing portion of the Fort Union region of the Northern Great Plains. Major patterns of elemental variations in lignite are related to factors affecting accumulation of both organic and inorganic components during deposition and aqueous precipitation, dissolution, and ion-exchange processes after deposition. Variations in overburden and underclay are dependent upon specific clay mineral variation and relative abundances of quartz- and feldspar-rich silt fractions versus clay mineral-rich fractions of the sediment, as well as upon local variation in carbonates and other elements. 8 figures, 5 tables. (ERA citation 08:040022)