Age constraints on fluid inclusions in calcite at Yucca Mountain

Title: Age constraints on fluid inclusions in calcite at Yucca Mountain

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Abstract

The {sup 207}Pb/{sup 235}U ages for 14 subsamples of opal or chalcedony layers younger than calcite formed at elevated temperature range between 1.88 {+-} 0.05 and 9.7 {+-} 1.5 Ma with most values older than 6-8 Ma. These data indicate that fluids with elevated temperatures have not been present in the unsaturated zone at Yucca Mountain since about 1.9 Ma and most likely since 6-8 Ma. Discordant U-Pb isotope data for chalcedony subsamples representing the massive silica stage in the formation of the coatings are interpreted using a model of the diffusive loss of U decay products. The model gives an age estimate for the time of chalcedony formation around 10-11 Ma, which overlaps ages of clay minerals formed in tuffs below the water table at Yucca Mountain during the Timber Mountain thermal event.

Authors:: Neymark, Leonid A; Amelin, Yuri V; Paces, James B; Peterman, Zell E; Whelan, Joseph F

Publication Date:: 2001-04-29

Research Org.:: U.S. Geological Survey, Denver, CO (US)

Sponsoring Org.:: US Department of Energy (US)

OSTI Identifier:: 794113

DOE Contract Number:: AI08-97NV12033

Resource Type:: Conference

Resource Relation:: Conference: 2001 International High-Level Radioactive Waste Management Conference, Las Vegas, NV (US), 04/29/2001--05/03/2001; Other Information: PBD: 29 Apr 2001

Country of Publication:: United States

Language:: English

Subject:: 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; CALCITE; CLAYS; HIGH-LEVEL RADIOACTIVE WASTES; SILICA; WATER TABLES; YUCCA MOUNTAIN; INCLUSIONS; MINERALOGY; RADIOACTIVE WASTE FACILITIES; SITE CHARACTERIZATION; LEAD 207; URANIUM 235; ISOTOPE RATIO; ISOTOPE DATING; AGE-CONSTRAINTS; FLUID INCLUSIONS

Citation Formats


                    Neymark, Leonid A, Amelin, Yuri V, Paces, James B, Peterman, Zell E, and Whelan, Joseph F. Age constraints on fluid inclusions in calcite at Yucca Mountain.  United States: N. p., 2001. 
        Web.

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                    Neymark, Leonid A, Amelin, Yuri V, Paces, James B, Peterman, Zell E, & Whelan, Joseph F. Age constraints on fluid inclusions in calcite at Yucca Mountain.  United States.

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                    Neymark, Leonid A, Amelin, Yuri V, Paces, James B, Peterman, Zell E, and Whelan, Joseph F. Sun .  
        "Age constraints on fluid inclusions in calcite at Yucca Mountain".  United States.  https://www.osti.gov/servlets/purl/794113.

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@article{osti_794113,

  title        = {Age constraints on fluid inclusions in calcite at Yucca Mountain},

  author       = {Neymark, Leonid A and Amelin, Yuri V and Paces, James B and Peterman, Zell E and Whelan, Joseph F},

  abstractNote = {The {sup 207}Pb/{sup 235}U ages for 14 subsamples of opal or chalcedony layers younger than calcite formed at elevated temperature range between 1.88 {+-} 0.05 and 9.7 {+-} 1.5 Ma with most values older than 6-8 Ma. These data indicate that fluids with elevated temperatures have not been present in the unsaturated zone at Yucca Mountain since about 1.9 Ma and most likely since 6-8 Ma. Discordant U-Pb isotope data for chalcedony subsamples representing the massive silica stage in the formation of the coatings are interpreted using a model of the diffusive loss of U decay products. The model gives an age estimate for the time of chalcedony formation around 10-11 Ma, which overlaps ages of clay minerals formed in tuffs below the water table at Yucca Mountain during the Timber Mountain thermal event.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/794113},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2001},

  month        = {4}

}

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