A middle-Trlassic sequence of strata composed .of gypsumstlt beds has been reeognized in the middle-lower Yangtze Valley. The mineralization in the gypsum-salt beds is closely related to Yenshanian magmatism, During t...A middle-Trlassic sequence of strata composed .of gypsumstlt beds has been reeognized in the middle-lower Yangtze Valley. The mineralization in the gypsum-salt beds is closely related to Yenshanian magmatism, During the Yenshanian, magmatic intrusion activities were very active across evaporite beds, occupying great space in gypsum-salt beds. The magmatie rocks and the alterated country rocks are characterized by alkali-eurichment and halogen-enrichment. Copper and iron ores mainly occur in the evaporite beds or overlying levels. The genesis of endogenic copper and iron ores is commonly considered to be the consequence of interaction of magma with the gypsumsalt beds, i.e. there exists a close genetic connection between evaporites, magmatism and copper-iron ores. These observed features are of great significance both in practice and theory.展开更多
文摘A middle-Trlassic sequence of strata composed .of gypsumstlt beds has been reeognized in the middle-lower Yangtze Valley. The mineralization in the gypsum-salt beds is closely related to Yenshanian magmatism, During the Yenshanian, magmatic intrusion activities were very active across evaporite beds, occupying great space in gypsum-salt beds. The magmatie rocks and the alterated country rocks are characterized by alkali-eurichment and halogen-enrichment. Copper and iron ores mainly occur in the evaporite beds or overlying levels. The genesis of endogenic copper and iron ores is commonly considered to be the consequence of interaction of magma with the gypsumsalt beds, i.e. there exists a close genetic connection between evaporites, magmatism and copper-iron ores. These observed features are of great significance both in practice and theory.