中国主要含镍岩体特征及其成因

Geplogical Setting and Genesis of Major Nickel-bearing Rock Bodies in China

中国目前已发现7条岩带中18个岩体赋存有工业铜镍矿床。这些含镍岩体的岩石组合有三大类,其中以超基性岩中矿床居多,苏长岩与科马提岩中较少。中国含镍岩浆系列属于科马提岩系列而非拉斑玄武岩系列,含矿岩浆来自上地幔的部分熔融,源区具有U、Th值高而Cr低的特点,深大断裂发育的大陆边缘是镍矿床发育最理想的场所。

Oopper--nickel deposits of industrial value have so far been found in eigh--teen rock bodies along seven rock belts of China. According to their rock as--semblages, these nickel--bearing rock bodies might be divided into three types:ultrabasic rocks, norite and komatiite, with most ore deposits occurring in thefirst type. Metallization shows the character that small rock bodies formedlarge nickel deposits. The nickel--bearing magma is of komatiite series insteadof belonging to tholeiitic series. The ore--forming magma was formed throughpartial melting of the upper mantle, with the source area characterized by en--richment of U and Th and depletion of Cr. The continental margin with welldeveloped deep faults is the most favorable place for the development of ni--ckel deposits.