(1. 国家海洋局 第一海洋研究所 海洋沉积与环境地质国家海洋局重点实验室，青岛 266061；
2. 青岛海洋地质研究所 海洋地质实验测试中心，青岛 266071)
摘 要: 为了进一步了解富钴结壳中Ti的元素地球化学特征，对中太平洋M海山一块富钴结壳C5进行元素化学和矿物学分析。结果表明：样品C5具有新老两个生长世代壳层，相对于新壳层，老壳层除含水羟锰矿、非自形FeOOH∙xH2O、石英、长石和方解石等矿物外，还含碳氟磷灰石、钡镁锰矿和针铁矿；老壳层中Ti的平均质量分数为0.75%，富集于铁矿物相和碎屑矿物相中，来源于海水和碎屑；新壳层中Ti的平均质量分数为1.92%，主要来自海水中，通过晶格替代过程富集于锰矿物相；另外，Ti的富集也可能受动力过程控制，但Ti的富集通量在生长过程中非恒定，这可能源于其物源多样性；富钴结壳是潜在的海底钛矿资源。
关键字: 富钴结壳；钛；富集机理
（1. Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography,
State Oceanic Administration, Qingdao 266061, China;
2. The Experiment and Testing Center for Marine Geology, Qingdao Institute of Marine Geology,
Qingdao 266071, China）
Abstract: One cobalt-rich crust C5 from M seamount in Central Pacific Ocean was analyzed mineralogically and chemically to understand the geochemical characters of Ti in cobalt-rich crust. The results show that the cobalt-rich crust C5 shows two growth generations, the lower older section and the upper younger section. The older section contains the carbonate-fluorapatite todorokite and goethite, besides vernadite, amorphous FeOOH∙xH2O, quartz, feldspar and calcite, which occur in the younger section. The Ti in the older section has an average mass fraction of 0.75%, which enriches in iron mineral phase and detrital mineral phase and origins from seawater and clastic minerals. In the younger section, the content of Ti is 1.92%, which enriches in manganese mineral phase through lattice-substituting and origins from seawater. Furthermore, dynamic process controls partly the enrichment of Ti in crust. However, the enrichment fluxes of Ti change during the cobalt-rich curst growing, which could be induced by the multiple material sources. The cobalt-rich crust is a potential Ti resource on the seafloor.
Key words: cobalt-rich crust; titanium; enrichment mechanism
