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Chapter 7: Studies of short-lived radionuclides in Santorini volcanics

T. H. Druitt·L. Edwards·R. M. Mellors·D. M. Pyle·R. S. J. Sparks·Marvin A. Lanphere·M. Davies·B. Barreirio
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Abstract

Disequilibria between the short-lived radioactive nuclides 226 Ra, 230 Th and 238 U in young volcanic rocks can be used both for dating the time of crystallisation of a rock, and as isotopic tracers of the sources of magmas and the chemical evolution of volcanic systems. The principles of these methods have been reviewed extensively elsewhere (Condomines et al . 1988; Gill et al . 1992; Gill & Condomines 1992; Macdougall 1995). In this chapter, we present new 238 U- 230 Th- 226 Ra disequilibria data for the Thera pyroclastics and for selected lavas. These data complement the radiogenic isotopic data presented in Chapter 6 on the compositional evolution through time of the pyroclastic ejecta. In particular, we find that the ( 230 Th/ 232 Th) isotopic ratio corrected to the time of eruption varies in a systematic way with time through the second cycle of the Thera pyroclastics and variations in this ratio are correlated with the variations of 87 Sr/ 86 Sr, 143 Nd/ 144 Nd and Pb isotopes.

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Geological Society, London, MemoirsArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 36.332103° to 36.482241° latitude; 25.353444° to 25.488055° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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T. H. Druitt, L. Edwards, R. M. Mellors, D. M. Pyle, R. S. J. Sparks, Marvin A. Lanphere, M. Davies, B. Barreirio. 1999-12-09. Chapter 7: Studies of short-lived radionuclides in Santorini volcanics. https://doi.org/10.1144/gsl.mem.1999.019.01.07

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