Sanjiang orogen is a NS-trending collisional orogenic belt between Indian plate and Yangtze block of the South China plate, and also an important metallogenetic belt in southwestern China. The collision process between Eurasia plate and Indian plate started from Mesozoic times, which resulted in strong and frequent magmatic activities then after. After Cenozoic, the stronger and more frequent tectono-magmatism and volcanic eruptions provided fracture spaces and plenty of heat sources for epithermal activity in this area. As an active geothermal field, the Rehai geothermal field situates in the southern part of the Sanjiang orogen, and is composed of two sub-scale geothermal fields-the Huanggua-qing-Liuhuang-tang in northeast and Reshui-tang in southwest. Rocks that outcrop in this geothermal field are mainly late Cretaceous granitoids with minor late Tertiary and Quaternary volcanics, sandstone and conglomerate. Strong volcanisms in Pliocene to Pleistocene were recognized and early Pleistocene dacite and andicitic terrestrial volcanics distribute in the Huanggua-qing-Liuhuangtang geothermal field (i.e. Rehai geothermal field in narrow sense). 62 hot spring groups occur along a NS-striking main fault in the Rehai geothermal field. Hydrochemical types of the spring water are mainly Na-Cl-HCO₃ and Na-HCO₃-Cl types, secondly Na-SO₄ type, Na-Cl type, Ca-Na-HCO₃-SO₄ type and Mg-Ca-HCO₃ type.Temperature of spring water on the surface is 24～102°C, and pH value is 2～9.8. Geothermometers of SiO₂, Na/K, Na-K-Ca, and Na-K-Ca-Mg, of the hot spring waters in the Rehai geothermal field, were used to evaluate the reservoir temperature, which yielded results of >270～100℃ from below 600 m to the surface. The hydrothermal alteration and gold mineralization process are still going on in that area, and the Lianghe gold deposit was formed between the Zao-tang River and the Xiao-shui River in Liuhuang-tang-Huanggua-qing geothermal area in the northeast sector of the geothermal field. This deposit is about 6 km² in area, with several kinds of spring sinter, hydrothermal alteration and breccia, and is one of the most recently formed hot spring-type gold deposits in China.Au content in hot spring water, surface sinter, bottom sinter, acid leaching zone, and stockwork quartz veins, is 0.01～0.16 ppb, 0.001～0.63 ppm, 0.004～0.17 ppm, 0.001～0.73 ppm, and 0.003～4.65 ppm, respectively. Ag content in silica cap reaches 0.001～54.5 ppm. Based on the average of Au and Ag content, Au/Ag ratio is always less that 0.1 (1 : 10～1 : 19）. δ¹⁸O_H2O，δD_H2O, and δ¹³C_CO2, values of hot spring waters in the Tengchong Lianghe area are -12.3‰～-5.1‰,　-68.9‰～-55.7‰，and -5.2‰～-1.6‰，respectively.　δ³⁴S　values of hot spring water, native sulfur, and sulfides such as pyrite, are mainly -2‰～＋2‰. Liquid composition of fluid inclusions in quartz from breccia of Liuhuang tang area is H₂O 72%, H₂S 28%; vapor composition is CO₂ 67.1%, H₂S 12.6%, and H₂ 20.3%. The δ¹⁸O values for quartz from quartz veins in the Lianghe gold deposit are between 5.0‰ and 8.8‰ (averaged 7.3‰ for 10 samples), and 2.3‰～12.4‰　(averaged 7.6‰ for 6 samples) for silicified Pliocene sandstone (whole rock). Soil and rock geochemical investigation results suggest a tendency of high concentration or anomalies of Bi, Li, Rb, As, Sb, Hg, and Sn in or near hot spring areas, and Mn, Ni, Co, Pb, and Zn around or out of hot spring areas.

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本論の目的は、私自身が調査地の映像実践に巻き込まれながら、徳宏タイ族の人びとから学んだ現地の映像ナラティブと、そのプロセスで私自身が得た感覚的経験を考察し、いかにして人類学的映像ナラティブを実現したのかを明らかにすることである。近年、映像制作機器の小型化と低廉化によって、映像制作は身近なものとなり、人類学者が赴く調査地でも様々な映像実践が見られるようになった。本稿の調査地のように、これまで被写体であった人びとが、自分たちの文化的実践を映像に記録し、自主制作した記念映像をローカル市場において流通させ、鑑賞するようになった社会もある。本論では、私が現地の映像実践に参与して得た感覚的経験について民族誌的記述をおこなう。それとともに人類学者が現地の映像文化を身をもって学び、そのなかで培われる感覚や獲得される気づきを人類学研究に還元する、という相互の感覚や映像の表現方法を交渉させていくプロセスを、映像人類学の一つの方法論として提示し、今後の民族誌的調査と研究における映像の活用に寄与したい。

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