为了考察石英表面特征对金沉淀的影响，于20―200℃使不同切向的石英晶体光片与含金氯化物溶液相互作用。反应前后石英光片表面的SEM/EDAX、XPS和反光显微镜研究表明，所有实验中均发现金在石英表面沉淀。结合显露石英位错的浸蚀实验，发现沉淀的金晶体在石英表面的分不死守石英晶体中存在的线性缺陷控制。本文分析了本实验研究结果与前人工作的差异，讨论了金的沉淀机理和含金石英脉中金的不均匀分布。

The solubility of the buffer assemblage magnetite+hematite in 0.10, 1.00 and 3.00 mol/kg NaCl solutions with various pH values was determined by use of a Dickson gold cell hydrotherma1 apparatus at 300℃ and 500 bars. Activities of H+ and Cl-in the NaCl hydrothermal solution for each determination were approximated. The experimental results show that the solubility is strongly dependent on the pH of the solutions and appears to have no explicit relation to NaCl molality in acidic solutions. The correlation of the measured solubility with pH at 300℃ suggests a change in Fe speciation in solution at pH≈5.3-5.4. Treatment of the experimental data by a ridge regressions program and an iterative procedure indicates that the dominant species in solution under the run condition are FeOH+, Fe(OH)3Cl-, Fe(OH)03 and Fe(OH)-4. Gibbs free energy of formation for these species at 300℃ and 500 bars were derived: 0ΔGf,FeOH+=-250.4 kJ/mol; ΔG0f,Fe(OH)3Cl−=-644.7 kJ/mol; ΔG0f,FeOH03=-552.6 kJ/mol; and ΔG0f,FeOH-4=-652.7 kJ/mol. The Present study demonstrates that the change in acidity of hydrothermal ore-forming solutions exerts an important influence on the transport and deposition of Fe in nature.

本文于300℃，500bar时，用金袋式热液设备测定了MH（磁铁矿+赤铁矿）缓冲组合在HCl水溶液中的溶解度。计算了热水溶液中离子的活度，并用岭回归和叠代的方法处理实验数据，与多种可能的Fe存在形式模型拟合。结果表明，实验溶液中的Fe主要成FeOH+存在。求得MH组合溶解反应的平衡常数K=57.161。计算了0f,FeOH+ΔG＝260.3kJ/mol。300℃时，在地质上可能的pH和氯化物浓度条件下，热液中的Fe主要成羟络合物存在。

In order to verify the presence of residual organic matter in some S-type granites, a method used conventionally in petroleum geochemistry for isolation of kerogen was employed to separate carbonaceous material (CM) from the Xihuashan granite, Jiangxi Prov., China. Optical, XRD and SEM/EDAX analyses identified the acid-insoluble residue as mainly composed of various mineral debris, with a minor carbonaceous fraction found in the residue. LMR and micro-FTIR studies showed that the residue contained a small amount of CM, which is heterogeneous in composition and structural state. The occurrence of CM in the granite implies that this granitic magma originated from sediments and crystallized at relatively lower temperatures and high pressures. This deduction is consistent with geological and geochemical studies of the Xihuashan granite. A tentative model was suggested which connects CM in S-type granite with organic matter in sedimentary rocks. The conditions under which CM can be preserved in S-type granite are discussed. The occurrence of some heavy hydrocarbons is expected in the Xihuashan granite.