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Chemistry Of Maceral And Groundmass Density Fractions Of Torbanite And Cannel Coal, Zhiwen Han, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Microscopically, torbanite and cannel coal are composed of coarser macerals set in a fine-grained to amorphous groundmass. It is often assumed that the amorphous groundmass is genetically related to the distinct macerals. The separation of macerals and groundmass from 14 late Paleozoic torbanite, cannel, and humic coals permits the analysis of individual constituents using elemental analysis and flash pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster and principal component analyses of the Py-GC/MS data further reveal the chemical similarities and differences between the various constituents. Pyrolyzates of Botryococcus-related alginites are characterized by an abundance of normal alkadienes, alkenes, and alkanes. Even their …

Geochemical Characterization Of Maceral Concentrates From Herrin No. 6 Coal (Illinois Basin) And Lower Toarcian Shale Kerogen (Paris Basin), B Artur Stankiewicz, Michael A. Kruge, John C. Crelling

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Density gradient centrifugation (DGC) is a physical method for the separation of sedimentary organic matter into its constituents. Using DGC, it is possible to prepare maceral concentrates from a single sample, which are amenable to microanalysis. DGC fractions from a coal sample from the Illinois Basin (Herrin No. 6, Upper Carboniferous) and from the kerogen of a marine shale sample from the Paris Basin (Lower Toarcian) were analyzed by flash pyrolysis-gas chromatography-mass spectrometry, after extraction by CH₂Cl₂.

Chemical differences between the coal DGC fractions are the easiest to recognize, indicating very distinctive biological precursors. For example, …

Organic Geochemical And Petrographic Analysis Of Pure Macerals From The Ohio Shale, Michael A. Kruge, Susan M. Rimmer, John C. Crelling

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Recent advances now permit the separation of coal into constituent macerals of high purity using density gradient centrifugation (DGC). With the availability of pure macerals, the chemical structure of each can be investigated separately, without the interactive interference of the other macerals or mineral matter. The present study is a preliminary effort applying these methods to the study of oil shale kerogen.

We have used a sample from the Huron Member of the Upper Devonian Ohio Shale from Logan County, Ohio. Whole rock petrographic examination revealed intact Tasmanites, telalginite of unknown derivation and a weakly fluorescing matrix. Pyrite is abundant, …