Isotopic evidence for paleohydrologic evolution of ground-water flow paths, southern great plains, United States

Journal Article · Sat Jul 01 00:00:00 EDT 1989 · Geology; (USA)

DOI:https://doi.org/10.1130/0091-7613(1989)017<0653:IEFPEO>2.3.CO;2· OSTI ID:7242937

Dutton, A; Simpkins, W W ^[1]

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1. Univ. of Texas, Austin (USA)

A confined aquifer in Triassic Dockum Group sandstone beneath the southern Great Plains was isolated from hypothesized paleorecharge areas in eastern New Mexico by Pleistocene erosion of the Pecos and Canadian river valleys and formation of hydrologic divides. Truncation of the flow system left meteoric water in the confined aquifer with mean {delta}D and {delta}{sup 18}O values that are 17{per thousand} and 2.0{per thousand}, respectively, lighter than those in the overlying High Plains aquifer. Thick upper Dockum mudstone retards downward flow from the High Plains aquifer, which has been recharged by isotopically heavy precipitation during the Holocene. Recharge to the confined aquifer occurred at altitudes of 1600 to 2200 m in proximal Dockum sandstone facies since eroded in eastern New Mexico, at a mean temperature 3 C cooler than present temperature across the southern High Plains. Effect of Pleistocene climatic change on isotopic composition of Dockum ground water could be superposed over geomorphologic effects.

• OSTI ID: 7242937
• Journal Information: Geology; (USA), Vol. 17:7; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
GREAT BASIN
GEOLOGIC HISTORY
HYDROLOGY
GROUND WATER
ISOTOPE RATIO
AQUIFERS
DEUTERIUM
GEOLOGIC MODELS
METEORIC WATER
OXYGEN 18
PALEOCLIMATOLOGY
PLEISTOCENE EPOCH
RECHARGE
SANDSTONES
SILTSTONES
CENOZOIC ERA
EVEN-EVEN NUCLEI
GEOLOGIC AGES
HYDROGEN COMPOUNDS
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
NORTH AMERICA
NUCLEI
ODD-ODD NUCLEI
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PALEONTOLOGY
QUATERNARY PERIOD
ROCKS
SEDIMENTARY ROCKS
STABLE ISOTOPES
USA
WATER
580000* - Geosciences