1980
DOI: 10.1016/0012-821x(80)90008-4
|View full text |Cite
|
Sign up to set email alerts
|

U-Pb ages of uraniferous opals and implications for the history of beryllium, fluorine, and uranium mineralization at Spor Mountain, Utah

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
2
1
1
1

Citation Types

0
8
0

Year Published

1986
1986
2015
2015

Publication Types

Select...
6
1

Relationship

0
7

Authors

Journals

citations
Cited by 31 publications
(8 citation statements)
references
References 20 publications
0
8
0
Order By: Relevance
“…Some support for this model is provided by V-Pb ages of opal nodules in the beryllium tuff. One of these zoned nodules has ages that decrease outward from 20.8 ± 1.0 Ma to 8.2 Ma (Ludwig et al 1980). These results suggest that the mineralized nodules formed at the same time as the rhyolite erupted, but continued to grow (perhaps episodically) by the deposition of opal from ground water.…”
Section: ' 113°112°imentioning
confidence: 79%
“…Some support for this model is provided by V-Pb ages of opal nodules in the beryllium tuff. One of these zoned nodules has ages that decrease outward from 20.8 ± 1.0 Ma to 8.2 Ma (Ludwig et al 1980). These results suggest that the mineralized nodules formed at the same time as the rhyolite erupted, but continued to grow (perhaps episodically) by the deposition of opal from ground water.…”
Section: ' 113°112°imentioning
confidence: 79%
“…/j.gca.2008 terrestrial records. The U-Pb system in opal and chalcedony allows dating in the age range from $50 ka to millions of years and older (Ludwig et al, 1980;. Recently, the reliability of U-Pb dating of opal was questioned on the basis of idea that large Rn-produced excesses of 206 Pb and 207 Pb would result in both 206 Pb/ 238 U and 207 Pb/ 235 U ratios that grossly overestimate mineral deposition ages Dublyansky, 2002a,b, 2006;Dublyansky et al, 2003).…”
Section: Introductionmentioning
confidence: 98%
“…The most pertinent compositional data for the purposes of dating opal are concentrations of U relative to Th (for 230 Th/U dating) and U relative to Pb (for U-Pb dating). U concentrations in the 76 analyses from 13 localities reported by Gaillou et al (2008) range from 0.01 to 131 mg/g, although U concentrations from hundreds to thousands of mg/g have been reported from other localities (Ludwig et al 1980;Paces et al 2010, supplement). Like REE, tetravalent U and Th are largely insoluble in aqueous solutions; therefore, U/Th ratios in opal can remain similar to values found in host rocks (typically 0.1-0.5).…”
Section: Mineralogy and Geochemistry Of Opalmentioning
confidence: 91%
“…U-Pb isotopic compositions were also investigated to evaluate the possible use of uraniferous opal and chalcedony as geochronometers. Ludwig et al (1980) found that opal-CT with U concentrations of 84.5-3,940 mg/g at Spor Mountain, Utah, USA, had low common Pb contents and high retention of U-daughter products. Two distinct U AR values, Ludwig et al (1980) concluded that Spor Mountain opals approximated a closed system for U and its daughter products and that U-Pb dating of opal as young as~1 Ma was possible.…”
Section: Initial Investigations Of Opal As a Geochronometermentioning
confidence: 97%
See 1 more Smart Citation