Strontium isotope geochemistry of calcite fracture fillings in deep core, Yucca Mountain, Nevada; A progress report

Conference · Sun Nov 01 04:00:00 EST 1992

OSTI ID:140843

Peterman, Z E; Stuckless, J S; Marshall, B D; Mahan, S A; Futa, K ^[1]

---

1. US Geological Survey, Denver, CO (US)

This paper reports on the variation of {sup 87}SR/{sup 86}Sr in calcite fracture fillings as a function of depth which has been determined using samples from five boreholes at Yucca Mountain. The data group into three discrete populations. Within 400 m of the present-day land surface, the distribution of {sup 87}Sr/{sup 86}Sr for calcite fracture fillings is similar to that of calcretes and near-surface veins suggesting an origin by infiltrating meteoric water. Veins within a 100-m zone immediately about the modern water table have {sup 87}Sr/{sup 86}Sr values similar to those of ground water from the Cenozoic volcanic aquifer suggesting a past connection between the two through aqueous diffusion or a higher water level. {sup 87}Sr/{sup 86}Sr values for calcite fracture fillings below the water table are low (mean = 0.70909 {plus_minus} 0.00038) and similar to those of the host rocks. The surficial calcites and those in the vadose zone are clearly unrelated to the deep calcite fracture fillings.

• OSTI ID: 140843
• Report Number(s): CONF-920430--; ISBN 0-87262-891-4
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
BOREHOLES
CALCITE
DIFFUSION
ENVIRONMENTAL IMPACTS
EVALUATION
GEOCHEMISTRY
GEOLOGIC FRACTURES
HYDROLOGY
ISOTOPE RATIO
LEACHING
RADIOACTIVE WASTE FACILITIES
RADIONUCLIDE MIGRATION
SITE CHARACTERIZATION
STRONTIUM ISOTOPES
WATER
YUCCA MOUNTAIN
Yucca Mountain Project