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| A REVIEW ON ADAKITE |
| SUN Hong-wei1, WANG Hai-po1, ZHANG Jiong-fei2 |
1. Bureau of Geological Exploration and Mineral Development, Inner Mongolia 162650, China;
2. Shenyang Institute of. Geology and Mineral Resources, Shenyang 110033, China |
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Abstract Adakite was proposed over a decade ago. It is a kind of acid-intermediate and calc-alkaline igneous rock, with the stickup characteristics of SiO2 ≥ 56%, Al2O3 ≥ 15%, relatively depletive HREE and Y(Y ≤ 18×10-6, Yb ≤ 1. 9×10-6), high Sr(> 400×10-6), La/Yb and Sr/Y, as well as positive Sr anomaly but absent or slightly negative Eu anomaly. There are two types of adakites with different petrogenesis:one is formed by the melting of subducting young(≤ 25-30 Ma) slab, and the other is formed by the partially melting of basaltic lower crust under the continental accretion setting. Adakites are important indicators of ore deposits.
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Received: 09 January 2003
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2003, Vol. 12 
