The organic geochemistry of the Alum Shale, Sweden
Organic matter in the Alum Shale of Sweden has been affected post-depositionally by irradiation from U decay. Effects include: (1) lowering of kerogen H/C ratios; (2) decrease in amount of extractable bitumen; (3) increased aromaticity. Higher thermal maturity of Alum Shale bitumen than kerogen in Central Sweden suggest bitumen migration into the shale. The thermal immaturity of both Alum Shale bitumen and kerogen in Eastern Sweden (Gotland and Oland) indicate that Gotland's oil has either migrated from an area of higher thermal maturity or is the result of very localized heating, possibly from an igneous intrusion. Zn, Cu and Pb concentrations in asphaltenes from the Alum Shale show an inverse relationship with thermal maturity. Experimental hydrous pyrolysis of Alum Shale suggest that Zn, Cu and, to a lesser extent Pb, are mobile during petroleum generation in both bitumen and brine, whereas U is immobile. Nitrogen in naturally occurring gases from the Alum Shale of Ostergotland, Sweden is atmospheric in origin based on ratios of N{sub 2}/Ar. Helium is derived from the radioactive decay of U-based on He{sub 3} He{sub 4} ratios. {delta}{sup 34}S values of Alum Shale pyrite show a fractionation with coeval seawater of approximately 35 per mil, which along with high total S concentrations of over 15% in some samples, implies extensive metabolism of organic matter during early diagenesis by sulfate reducing bacteria. Pyrite {delta}{sup 34}S values are lighter than coexisting organic sulfur in the kerogen by an average of near 7 per mil. The difference is believed to be the result of rite formation earlier and at a relatively shallower sediment depth than organo-sulfur compounds due to the greater reactivity of iron with bacterially released hydrogen sulfide than organic matter.
- Research Organization:
- California Univ., Los Angeles, CA (USA)
- OSTI ID:
- 5801702
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BITUMENS
CHEMICAL COMPOSITION
KEROGEN
OIL SHALE DEPOSITS
GEOCHEMISTRY
ORGANIC MATTER
IRRADIATION
SWEDEN
ARGON
AROMATICS
ASPHALTENES
BRINES
COPPER
DECAY
DIAGENESIS
ENVIRONMENTAL TRANSPORT
GASES
HELIUM
HYDROGEN SULFIDES
ISOTOPE RATIO
LEAD
MATURATION
METHANE
NITROGEN
ORIGIN
PYRITE
PYROLYSIS
SULFATE-REDUCING BACTERIA
SULFUR 34
SULFUR CONTENT
URANIUM
ZINC
ACTINIDES
ALKANES
ASPHALTS
BACTERIA
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
ELEMENTS
EUROPE
EVEN-EVEN NUCLEI
FLUIDS
GEOLOGIC DEPOSITS
HYDROCARBONS
HYDROGEN COMPOUNDS
IRON COMPOUNDS
IRON SULFIDES
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LIGHT NUCLEI
MASS TRANSFER
MATERIALS
METALS
MICROORGANISMS
MINERAL RESOURCES
MINERALS
NONMETALS
NUCLEI
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
RARE GASES
RESOURCES
SCANDINAVIA
STABLE ISOTOPES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
SULFUR ISOTOPES
TAR
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
WESTERN EUROPE
040200* - Oil Shales & Tar Sands- Reserves
Geology
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040500 - Oil Shales & Tar Sands- Properties & Composition