玲珑花岗岩的成因演化及其与鲁东金矿的关系

PETROGENETIC EVOLUTION OF LINGLONG GRANITES AND THEIR RELATIONSHIP TO GOLD DEPOSITS IN EAST SHANDONG PROVINCE

Based on the major characteristics of the Linglong granites, the present paper deals with the petrogenetic evolution and their relationship to the gold deposits in East Shandong Province in aspects of protolith, environment of formation and hydrothermal alteration. The fundamental conclusions are: Linglong granites were formed under Proterozoic continent-continent collision environment, and are synorogenic granitic complex formed from the regional metamorphic Jiaodong Group by metasomatism-anatexis. The gold de-posits in East Shandong Province are medium-low temperature hydrothermal deposits genetically related to the anatexitic magma. The bimodal tholeiitic basalt series of the Late Archean Jiaodong Group acts not only as the protolith of the Linglong granites but also as the metallogenetic source bed of gold mineralization in East Shandong; the forming process of granite is a process of gold migration and reactivation from its metallogenetic source bed. The tectonic uplift, the brittle deformation and hydrothermal alteration after the formation of granite are the mechanisms for the migration and the final deposition of gold in the anatexitic magmatic hydrothermal solution along the tectonic belts.