Inorganic geochemistry of Illinois Basin coals

Conference · Thu Sep 01 04:00:00 EDT 1983 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:6576609

Chou, C L

Chemical and mineralogical compositions of more than 100 samples of Illinois basin coals have been examined from an existing data base. Multivariate statistical analysis of the data shows that variation of many trace elements is related to mineral impurities in coal, including pyrite, clay minerals, calcite, sphalerite, and quartz. Organic sulfur, germanium, and boron are associated primarily with organic matter. The high sulfur content in most Illinois basin coal results from seawater permeation immediately following peat deposition. Low-sulfur coal (< 2.5% total sulfur) occurs in restricted areas where the coal is overlain by a thick fluvial gray shale (such as the Energy Shale Member that overlies the Herrin Coal Member). The gray shale, which predates marine transgression, acted as an impermeable barrier that effectively reduced infiltration of seawater into the peat. The interpretation is consistent with sulfur-isotopic data indicating that bacterially reduced sulfate is a principal source of sulfur enrichment. High-sulfur coal is significantly enriched in molybdenum, boron, mercury, uranium, iron, and thallium relative to low-sulfur coal. Seawater is a possible source of the high molybdenum, boron, mercury, and uranium contents in high-sulfur coal. Concentrations of iron and thallium in seawater are very low, suggesting that these two elements were probably derived from a terrigenous source and transported to the swamp by rivers. Positive correlation between sulfur and all these trace elements in Illinois basin coal indicates that their variations are also related to the postdepositional sedimentary environment.

• Research Organization: Illinois State Geologicl Survey, Champaign
• OSTI ID: 6576609
• Report Number(s): CONF-8310301-
• Conference Information: Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Journal Volume: 67:9
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
&amp; Peat-- Properties &amp; Composition
011000 -- Coal
Lignite
&amp; Peat-- Reserves
Geology
&amp; Exploration
CARBONACEOUS MATERIALS
CHEMICAL COMPOSITION
CHEMISTRY
COAL
ENERGY SOURCES
FOSSIL FUELS
FUELS
GEOCHEMISTRY
ILLINOIS BASIN
INORGANIC COMPOUNDS
MATERIALS
MINERALOGY
SEDIMENTATION
SULFUR CONTENT