Sulfur isotope evidence for regional recharge of saline water during continental glaciation, north-central United States

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Geology; (USA)

DOI:https://doi.org/10.1130/0091-7613(1990)018<1054:SIEFRR>2.3.CO;2· OSTI ID:5796857

Siegel, D I ^[1]

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1. Syracuse Univ., NY (USA)

Sulfate concentrations in ground water from the Cambrian-Ordovician aquifer of south-eastern Wisconsin and northern Illinois increase up to hundreds of times where the aquifer is confined beneath the Maquoketa Shale. There is no sulfate source in the aquifer or overlying rocks except for minor amounts of finely disseminated pyrite. Coinciding with increasing sulfate concentrations, {delta}{sup 34}S of the dissolved sulfate increases from less than {minus}5{per thousand} in the unconfined part of the aquifer to a nearly constant value of +20{per thousand} where the aquifer is confined and where sulfate reduction is minimal. The most likely source for this isotopically heavy sulfate is ground water associated with Silurian evaporites under Lake Michigan. It is uncertain if the sulfate-rich water was emplaced in pulses or mostly during the last glaciation.

• OSTI ID: 5796857
• Journal Information: Geology; (USA), Journal Name: Geology; (USA) Vol. 18:11; ISSN GLGYB; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AQUIFERS
CHEMISTRY
CONTAINMENT
ECOLOGICAL CONCENTRATION
EVAPORITES
EVEN-EVEN NUCLEI
FEDERAL REGION V
FLUID FLOW
GEOCHEMISTRY
GEOLOGIC AGES
GEOLOGIC HISTORY
GLACIERS
GREAT LAKES
GROUND WATER
HYDROGEN COMPOUNDS
HYDROLOGY
ILLINOIS
ISOTOPE RATIO
ISOTOPES
LAKE MICHIGAN
LAKES
LIGHT NUCLEI
LIQUID FLOW
NORTH AMERICA
NUCLEI
ORIGIN
OXYGEN COMPOUNDS
PALEOZOIC ERA
RECHARGE
ROCKS
SEDIMENTARY ROCKS
SHALES
SILURIAN PERIOD
SOURCE ROCKS
STABLE ISOTOPES
SULFATES
SULFUR 34
SULFUR COMPOUNDS
SULFUR ISOTOPES
SURFACE WATERS
USA
WATER
WISCONSIN