## 4 Results
### Major Element Contents  
Major elemental analyses (Table 1) indicate that the Dahongliutan pluton is silica-rich (SiO\({}_{2}\) =53.91-73.95 wt.%; average = 68.33 wt.%). The Al\({}_{2}\)O\({}_{3}\) content is 12.81-17.41 wt.% (average = 15.08 wt.%), and the aluminum saturation index (A/CNK) ranges from 1.01 to 1.43, indicating peraluminous rocks (Figure 3a). The Na\({}_{2}\)O content is 2.06-3.39 wt.% (average = 2.72). The K\({}_{2}\)O content is 1.76-6.60 wt.% (average = 3.98 wt.%) and the K\({}_{2}\)O/Na\({}_{2}\)O ratio is 0.53-2.73 (average = 1.49). The total alkali content (K\({}_{2}\)O + Na\({}_{2}\)O) ranges from 4.24 wt.% to 9.02 wt.% (average = 6.7). The alkali aluminum index (AI) is 0.24-0.63 (average = 0.45) and the Rittman Portfolio Index (\(\sigma\)) ranges from 0.96 to 3.18, with all values \(<\) 3.3 (average = 1.82), thereby exhibiting typical calc-alkaline characteristics. On an SiO\({}_{2}\)-K\({}_{2}\)O diagram (Figure 3b), the samples fall in the high-potassium calc-alkaline series region. The CaO and TiO\({}_{2}\) contents are low (0.82-6.47 wt.% and 0.13-0.87 wt.%, respectively). The MgO content is 0.21-3.75 wt.% (average = 1.22 wt.%). The total iron (TFeO) content is 1.28-9.49 wt.% (average = 4.07 wt.%), and the TFeO/MgO ratio ranges from 2.53 to 8.19 (average = 4.12), indicating the pluton is Fe-rich and Mg-poor. According to the calculated CIPW norms, corundum (0.16-4.58 wt.%) is present, indicating peraluminous characteristics. The differentiation index (DI) ranges from 40.3 to 90.51 (average = 75.69), indicating a high degree of magmatic differentiation. The consolidation index (SI) ranges from 1.97 to18.21 (average = 7.96), indicating that the magma underwent a high degree of fractional crystallization and was highly acidic. On a total alkali vs. silica (TAS) diagram (Figure 4), 17 samples plot in the granite region. In summary, the Dahongliutan pluton is therefore characterized by high silica, alkali, and potassium contents, but low MgO, TiO\({}_{2}\), MnO, and P\({}_{2}\)O\({}_{5}\) contents. These characteristics indicate that the pluton underwent strong fractional crystallization and is a peraluminous granite of the potassium-rich calc-alkaline series.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline
**Sample** & \begin{tabular}{c} **P19-** \\ **OXT01** \\ \end{tabular} & \begin{tabular}{c} **P20-** \\ **25 XT01** \\ \end{tabular} & \begin{tabular}{c} **P6-** \\ **25 XT01** \\ \end{tabular} & \begin{tabular}{c} **P22-55** \\ **25 XT01** \\ \end{tabular} & \begin{tabular}{c} **P22-55** \\ **66 XT01** \\ \end{tabular} & \begin{tabular}{c} **P22-** \\ **GS** \\ \end{tabular} & \begin{tabular}{c} **P26-88** \\ **GS** \\ \end{tabular} & \begin{tabular}{c} **P20-19** \\ **30 XT01** \\ \end{tabular} & \
\begin{tabular}{c} **P20-03** \\ **GS** \\ \end{tabular} &
\begin{tabular}{c} **P11-** \\ **GS** \\ \end{tabular} \\ \hline Component & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 & 11 & 12 \\ SiO\({}_{2}\) & 73.22 & 64.68 & 73.4 & 73.05 & 70.74 & 72.39 & 72.47 & 72.16 & 71.92 & 73.82 & 57.01 & 73.95 \\ TiO\({}_{2  
Figure 3: (a) A/NK vs. A/CNK (according to [PERSON], et al. [14]) and (b) K\({}_{2}\)O wt.% vs. SiO\({}_{2}\) wt.% plots for the Dahongliutan pluton (according to [PERSON], et al. [15]).