黑龙江秋皮沟铜矿床年代学与地球化学特征及成因

秋皮沟矿床位于小兴安岭-张广才岭成矿带延寿矿集区。在野外地质调查的基础上开展了锆石 LA--ICP--MS U--Pb 法测年、主量与微量元素测试。测试结果显示，主量元素中Ca、Ti、Al、Si 等在花岗岩、矽卡岩和大理岩间发生了迁入和迁出，含量呈线性变化关系。成矿岩体花岗岩属过铝质钙碱性系列花岗岩( A/CNK = 1. 26，Na2O/K2O = 0. 93，σ = 1. 27) ; 富集Rb、Th、U、Nd 等元素，亏损Sr、 P、Ti，具有与俯冲带岩浆岩地球化学相似的特征。各样品稀土配分模式轻稀土( LREE) 富集，重稀土( HREE) 亏损，具轻微的Eu 负异常，其相似的REE 配分模式表明它们在成因上具内在联系。花岗岩锆石U--Pb 谐和年龄184. 1 ± 2. 2 Ma，属于早侏罗世。秋皮沟矿床的形成晚于184. 1 ± 2. 2 Ma，可能与太平洋板块俯冲有关。

Chronology, geochemical characteristics and genesis of Qiupigou copper deposit in Heilongjiang

Qiupigou deposit is located in the Lesser Xing'an range--Zhangguangcai range metallogenic belt． The systemic field geological survey，zircon LA--ICP--MS U--Pb dating，test of major and trace element results show that the major elements ( Ca，Ti，Al，Si，etc) are transferring among marble，skarn and limestone rocks， and the content of the elements among these rocks exhibits a linear change． The mineralization granites belong to ultraluminum and calc-alkaline rocks ( A/CNK = 1. 26，Na2O/K2O = 0. 93，σ = 1. 27) ． The granites is enriched in Rb，Th，U，Nd，Yb，and depletion in Sr，P，Ti，which is compatible with the geo-chemical characteristics of subduction magma． The distributing pattern of rare elements are rich in LREE and deficient in HREE with negative Eu abnormalities． The same REE distributing patterns show that the granites have some relation in petrogenesis． The zircon U--Pb ages of 184. 1 ± 2. 2 Ma show the granites formed in Early Jurassic． The Qiupigou deposit was formed later than 184. 1 ± 2. 2 Ma and probably related to subduction of the Paleo-Pacific．