中文摘要:内蒙古羊蹄子山-磨石山是本项目组近几年来发现和勘查研究的一个以锐钛矿为主的沉积变质型钛矿床，是钛矿床的一个新的成因类型。矿体产于中元古代二道凹群变质岩〔（1 751±8） Ma〕中，其围岩为石英绢云片岩、绢云石英片岩、变质（粉）砂岩和斜长角闪岩等。矿石实际上是富含锐钛矿等钛矿物和直闪石、黑云母的变质石英（粉）砂岩和片岩。斜长角闪岩是矿体的重要围岩之一，多呈似层状、透镜状产出，与矿体在时、空、成因上有密切关系。按矿物组合特征，斜长角闪岩可分为角闪岩、斜长角闪岩和斜长岩等3类。恢复其原岩，大致相当于苦橄玄武岩、玄武岩、玄武安山岩和粗面质安山岩。岩石化学和微量元素地球化学特征表明，它们主要属于活动大陆边缘岛弧和洋脊过渡带的拉班玄武岩类，而且岩石分异演化较彻底。矿体和斜长角闪岩都是海底基性火山活动的产物，后又遭受了区域变质作用。
Abstract:The Yangtizishan-Moshishan sedimentary metamorphosed titanium ore deposit, discovered and explored by the authors in recent years, is of an anatase-dominated new genetic type. Ore bodies occur in metamorphic rocks of Middle Proterozoic Erdaowa Group (1 751±8 Ma), consisting of sericite-quartz schist, metamorphic quartz sandstone (siltstone), and amphibolite. The ores are actually anatase-bearing metamorphosed sandstone (siltstone) or schist.According to their mineral associations, three types of amphibolites may be recognized, i.e., amphibolite, plagioclase-amphibolite, and plagioclasite. Recovery of the amphibolites reveals that the initial rocks are picrite-basalt, basalt, basaltic andesite, and trachyte andesite.Petrochemical and trace element geochemical data suggest that the tectonic setting of these rocks belongs to the island arc or the transitional belt betweenisland arc and oceanic ridge. There exists rather thorough differentiation of the rocks. Anatase ore and amphibolites were all produced by oceanic volcanism, but later subjected to regional metamorphism of the intermediate degree.
keywords:geochemistry, petrology, amphibolites, anatase ore deposit, Yangtizishan-Moshishan, Inner Mongolia
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基金项目:国家自然科学基金(40773038)；内蒙古自治区地质勘查项目（05-1-TK01）
引用文本：
李大新，赵一鸣，王佩华，丰成友.2008.内蒙古羊蹄子山-磨石山锐钛矿矿床斜长角闪岩类的岩石学和地球化学特征[J].矿床地质,27(4):474~482Li DaXing, Zhao YiMing, Wang PeiHua and Feng ChengYou.2008.Petrology and geochemical characteristics of amphibolites in Yangtizishan-Moshishan anatase ore deposit, Inner Mongolia[J].Mineral Deposits27(4):474~482
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