skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Applications of isotope geochemistry to the reconstruction of Yucca Mountain, Nevada, paleohydrology -- Status of investigations: June 1996

Abstract

Tunneling of the Exploratory Studies Facility has offered the opportunity to sample and examine occurrences of secondary mineralization found in the unsaturated-zone tuffs of Yucca Mountain, nevada. Petrographic and paragenetic analyses, calcite and silica-phase stable isotopic analyses, and preliminary strontium tracer isotope and radiocarbon age analyses of these samples indicate that (1) an early stage of secondary mineralization consisting largely of chalcedony and quartz, but possibly with or slightly preceded by calcite, probably formed at warmer than ambient temperatures; (2) later secondary mineralization consisting of calcite and opal appears completely consistent with formation from percolation of surface infiltration whose solute load and carbon isotopic compositions reflect passage through the overlying soils; (3) based on textural studies, all unsaturated-zone secondary mineral occurrences exposed within the Exploratory Studies Facility tunnel, with the exception of the vapor-phase assemblages that formed at high temperatures during cooling of the tuffs, probably formed in unsaturated settings; and (4) calcite radiocarbon ages, based on preliminary results, have not been compromised by post-depositional exchange with carbon-bearing water and gases in the unsaturated zone.

Authors:
; ; ;
Publication Date:
Research Org.:
Geological Survey, Denver, CO (United States)
Sponsoring Org.:
USDOE Assistant Secretary for Human Resources and Administration, Washington, DC (United States)
OSTI Identifier:
677015
Report Number(s):
USGS/OFR-98-83
ON: DE99000505; TRN: 99:001040
DOE Contract Number:  
AI08-97NV12033
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 1998
Country of Publication:
United States
Language:
English
Subject:
05 NUCLEAR FUELS; YUCCA MOUNTAIN; RADIOACTIVE WASTE FACILITIES; SITE CHARACTERIZATION; GEOCHEMISTRY; ISOTOPE DATING; HYDROLOGY; GEOLOGIC HISTORY; MINERALIZATION; EXPERIMENTAL DATA

Citation Formats

Whelan, J F, Moscati, R J, Allerton, S B.M., and Marshall, B D. Applications of isotope geochemistry to the reconstruction of Yucca Mountain, Nevada, paleohydrology -- Status of investigations: June 1996. United States: N. p., 1998. Web. doi:10.2172/677015.
Whelan, J F, Moscati, R J, Allerton, S B.M., & Marshall, B D. Applications of isotope geochemistry to the reconstruction of Yucca Mountain, Nevada, paleohydrology -- Status of investigations: June 1996. United States. doi:10.2172/677015.
Whelan, J F, Moscati, R J, Allerton, S B.M., and Marshall, B D. Sun . "Applications of isotope geochemistry to the reconstruction of Yucca Mountain, Nevada, paleohydrology -- Status of investigations: June 1996". United States. doi:10.2172/677015. https://www.osti.gov/servlets/purl/677015.
@article{osti_677015,
title = {Applications of isotope geochemistry to the reconstruction of Yucca Mountain, Nevada, paleohydrology -- Status of investigations: June 1996},
author = {Whelan, J F and Moscati, R J and Allerton, S B.M. and Marshall, B D},
abstractNote = {Tunneling of the Exploratory Studies Facility has offered the opportunity to sample and examine occurrences of secondary mineralization found in the unsaturated-zone tuffs of Yucca Mountain, nevada. Petrographic and paragenetic analyses, calcite and silica-phase stable isotopic analyses, and preliminary strontium tracer isotope and radiocarbon age analyses of these samples indicate that (1) an early stage of secondary mineralization consisting largely of chalcedony and quartz, but possibly with or slightly preceded by calcite, probably formed at warmer than ambient temperatures; (2) later secondary mineralization consisting of calcite and opal appears completely consistent with formation from percolation of surface infiltration whose solute load and carbon isotopic compositions reflect passage through the overlying soils; (3) based on textural studies, all unsaturated-zone secondary mineral occurrences exposed within the Exploratory Studies Facility tunnel, with the exception of the vapor-phase assemblages that formed at high temperatures during cooling of the tuffs, probably formed in unsaturated settings; and (4) calcite radiocarbon ages, based on preliminary results, have not been compromised by post-depositional exchange with carbon-bearing water and gases in the unsaturated zone.},
doi = {10.2172/677015},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1998},
month = {11}
}