BASIC CHARACTERISTICS OF THE MESOZOIC INTRUSIONS ALONG THE YANGTZE RIVER, ANHUI
Xing Fengming (Anhui Institute of Geological Sciences,Hefei 230001)
The Mesozoic intrusions along the Yangtze area of Anhui are characterized by high alkaline, lower initial value of Sr (I_(Sr)≈0. 707), minimum Eu anomaly (δEu≈0. 9) and occurrences of copper, iron, sulphur and gold ore deposits, differing from others in China and abroad. They may be divided into four rock associations; (1) iron (or sulphur) ore deposit-related intermediate-basic intrusions represented by those in Ningwu area; (2) copper, sulphur and gold ore deposits-related intermediate-acid intru- sions represented by those in Tongling area; (3) uranium, copper and iron ore deposits-related,subalka- line rocks such as in Luzong area ; (4) granites. A clear zoning of intrusions occurs from along the Yangtze area,southward to the Jiangnan Old Land, with appearances of transitional zones.