华南地区是我国重要的金属矿产资源产地,除了发育大量的钨锡钼铋和稀土等金属矿产外,还有铜金矿床分布。本文通过对华南地区29个典型Cu-Mo-W-Sn矿床的时空分布及其与之有关的花岗质岩体的侵位年龄分析,探讨了与不同成矿类型有关的花岗质岩石的地球化学特征。本文认为华南地区10个典型的与Cu有关的矿床主要发生在180~170Ma、160~150Ma以及105~90Ma三个时期,而10个钨矿床主要集中于170~130Ma;4个W-Sn矿床集中于170~130Ma和120~110Ma;而5个Sn矿床则发育于170~150Ma、130~110Ma以及100~90Ma三个时期。Cu矿床主要与同熔型花岗岩有关,而Mo、W-Sn既与同熔型花岗岩有关,又与改造型花岗岩有关。在岩石地球化学上,与Cu-(Mo)-W-Sn成矿作用有关的花岗质岩石也表现出不同的地球化学特点,如,从Cu-(Mo)矿床到W-Sn矿床SiO2含量有逐渐增大、氧化性逐渐降低、还原性逐渐增加以及分异演化程度有逐渐增高的趋势。与Cu-(Mo)-Au矿床有关的花岗质岩石具有较低的SiO2(60.3%~68.1%),氧化性较高(Fe2O3/FeO=0.31~1.81),分异演化程度较低(Rb/Sr=0.05~3.3)的特点;与Cu-(Pb)-(Zn)矿床有关的花岗质岩石具有相对较高的SiO2(73.3%~75.2%),氧化性稍高(Fe2O3/FeO=0.68~1.74),分异程度稍低(Rb/Sr=10.8~57.8)的特点;而与Mo矿床有关的花岗质岩石具有较宽的SiO2(67.3%~76.2%)变化范围,氧化性稍低(Fe2O3/FeO=0.68~1.74),分异演化程度稍低(Rb/Sr=0.6~9.29);与W矿有关的花岗质岩石的SiO2含量为69.9%~80.1%,还原性稍低(Fe2O3/FeO=0.19~0.76),分异演化程度稍高(Rb/Sr=21.9~61.7);与W-Sn矿床有关的SiO2为74.8%~78.7%,还原性较低(Fe2O3/FeO=0.08~0.59),分异程度较高(Rb/Sr=10.8~139);与Sn矿床有关的花岗质岩石的SiO2为64.8%~76.9%,还原性高(Fe2O3/FeO=0.01~0.58),分异演化程度高(Rb/Sr=1~530)。在结合华南地区
The paper mainly focuses on the temporal and spatial distributions of 29 typical Cu-Mo-W-Sn deposits in South China, and the ages of related intrusive granitic rocks, and discusses the geochemical features of granitic rocks associated with various metallogenic types, such as SiO2 content, Fe2O3/FeO ratios, and Rb/Sr ratios. This study shows that 10 typical copper deposits in South China occurred mainly at 180~170Ma, 160-150Ma and 105~90Ma. , and are associated with syntexis granites (I type), whereas W-Sn are associated with both syntexis (I type) and transformed granite rocks(S type). Copper mineralization occurred at three episodes, namely, 180~170Ma, 160~ 150Ma and 150~90Ma. Tungsten was mineralized dominantly at 170 ~ 130Ma, W-Sn deposit at 170~ 130Ma and 120 ~ 110Ma, and tin deposits at 170 150Ma, 130~110Ma and 100~90Ma, respectively. The granites related to Cu-Mo-W-Sn mineralization show different geochemical characteristics. For example, SiO2 contents increase, oxidation state decrease, redox state increase gradually and higher fractionation occurs from Cu (Mo) deposits to Sn-W deposits. The granites related to Cu-(Mo)(Au) deposits contain less SiO2 (60. 3% ~68. 1%), high oxidization (Fe2O3/FeO=0.31~1.81), less fractionated (Rb/Sr=0.05~3.3) intrusions. In contrast, Cu-(Pb)(Zn) deposits have a high content of SiO2 (73.3 % ~ 75.2 %) and fractionated (Rb/Sr= 10.8 ~ 57.8) with similar oxidation (Fe2O3/FeO= 0.68~ 1.74) intrusions. Mo-bearing deposits have a wide range of SiO2 (67.3 ~ 76.2%), lowest fractionated (Rb/Sr = 0. 6 ~ 9. 29), and low oxidation (Fe2O3/FeO= 0. 29 ~ 0. 92)intrusions. The granites related to W deposits are associated with fractionated intrusion (Rb/Sr=21.9~ 61.7) of intermediate oxidation state (Fe2O3/FeO = 0. 19 ~ 0. 76) and higher SiO2 (69. 9% ~ 80. 1%). However, the W-Sn deposits is related to the intrusion, highly fractionated (Rb/Sr=10.8~139) and low reduce