| Abstract: | This study is an example of a new and powerful application of 40Ar/39Ar age spectrum dating of muscovite. It is now possible to establish time constraints necessary for solving some of the long-standing problems in economic geology. Beyond this, the unique geologic situation of Panasqueira has allowed us to quantify the thermal characteristics of muscovite. Published fluid inclusion data have been used to estimate a muscovite argon closure temperature of ~325??C during rapid cooling or short reheating and a temperature of ~270??C during slow cooling or extended reheating. Argon-loss patterns displayed by all dated muscovites resulted from reheating after original closure; the mechanism for this argon loss appears to have been argon transport by volume diffusion. Thus, 40Ar/39Ar age spectrum dating of muscovite can be used to evaluate thermal conditions controlling argon diffusion as well as age, duration, and number of episodes of mineralization. -from Authors |
| Genre: | Article |
| ProdID: | 70014466 |
| Citation Author: | Snee, L. W.; Sutter, J. F.; Kelly, W. C. |
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| Citation End Page: | 354 |
| Citation Issue: | 2 |
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| Citation Language: | English |
| Citation Larger Work Title: | Economic Geology |
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| Citation Number Of Pages: | 20 |
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| Citation Search Results Text: | Thermochronology of economic mineral deposits: dating the stages of mineralization at Panasqueira, Portugal, by high-precision 40Ar/ 39Ar age spectrum techniques on muscovite; 1988; Article; Journal; Economic Geology; Snee, L. W.; Sutter, J. F.; Kelly, W. C. |
| Citation Start Page: | 335 |
| Citation Volume: | 83 |
| Citation Year: | 1988 |
| Type: | citation/reference |
| Text: | Thermochronology of economic mineral deposits: dating the stages of mineralization at Panasqueira, Portugal, by high-precision 40Ar/ 39Ar age spectrum techniques on muscovite; 1988; Article; Journal; Economic Geology; Snee, L. W.; Sutter, J. F.; Kelly, W. C. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Fri, 1 Jan 1988 00:00 -0600 |
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