K-Ar and Ar-Ar Dating
نویسنده
چکیده
The aim of this chapter is to present the K-Ar and Ar-Ar dating techniques in the context of noble gas studies, since there are already several recent texts on K-Ar and ArAr dating (Dickin 1995; McDougall and Harrison 1999). The focus of this section will be aspects of argon transport and storage in the crust, which affect K-Ar and Ar-Ar dating including Ar-loss from minerals by diffusion and Ar-gain by minerals or “excess argon.”
منابع مشابه
Ar-Ar dating of authigenic K-feldspar: quantitative modelling of radiogenic argon-loss through subgrain boundary networks
Ar–Ar dating of authigenic K-feldspar: Quantitative modelling of radiogenic argon-loss through subgrain boundary networks Journal Article How to cite: Mark, D. F.; Kelley, S. P.; Lee, M. R.; Parnell, J.; Sherlock, S. C. and Brown, D. J. (2008). Ar–Ar dating of authigenic K-feldspar: Quantitative modelling of radiogenic argon-loss through subgrain boundary networks. Geochimica et Cosmochimica Ac...
متن کاملNew Age Constraints on the Metamorphic Evolution of the High-Pressure/Low-Temperature Belt in the Western Tianshan Mountains, NW China
The western Tianshan high-pressure/low-temperature orogenic belt in NW China contains eclogite-facies metavolcanic rocks and omphacite-bearing blueschists. Previous Sm-Nd (omphacite, garnet, glaucophane, whole rock) and Ar/Ar (crossite) dating of eclogite-facies rocks has suggested an age of ca. 345 Ma as the best approximation for the timing of peak metamorphic conditions. The samples describe...
متن کاملA double-spike method for K–Ar measurement: A technique for high precision in situ dating on Mars and other planetary surfaces
A new method for K–Ar dating using a double isotope dilution technique is proposed and demonstrated. The method is designed to eliminate known difficulties facing in situ dating on planetary surfaces, especially instrument complexity and power availability. It may also have applicability in some terrestrial dating applications. Key to the method is the use of a solid tracer spike enriched in bo...
متن کاملDating transitionally magnetized lavas of the late Matuyama Chron: Toward a new Ar/Ar timescale of reversals and events
The K-Ar based geomagnetic polarity timescale was constructed using data from lavas and tuffs that bracketed, but rarely dated, the transitions between polarity intervals. Subsequent Ar/Ar dating indicated that the ages of some polarity transitions had been underestimated by about 6%. Although the accepted ages of the polarity chron boundaries have increased, their precise temporal definition r...
متن کاملA Triassic/jurassic Boundary Age for the Rochechouart Impact Structure (france)
Introduction: The age of the ~23 km in diameter Rochechouart impact structure, France, hosted by Precambrian to Paleozoic (Variscan) crystalline rocks of the northwestern French Massif Central, has long time been a matter of debate. Previous studies, including K-Ar, Rb-Sr, apatite and glass fission track, as well as paleomagnetic dating (see [1] for summary of ages), resulted in a broad (Middle...
متن کامل