11:00 AM - 11:15 AM
[MGI31-07] Evaluation of the artificial slopes based on the red relief map in the Yu-no-oku gold mining ruin
Keywords:Yu-no-oku gold mining ruin, Red relief map
The Yu-no-oku Gold Mining Ruin is a general term referring to the Nakayama, Kayagoya, and Uchiyama gold mining ruins. These ruin reached their peak in operation from the Sengoku period to the Edo period. This area is located on Mt. Kenashi in the southern part of Yamanashi Prefecture. Geologically, it belongs to the Nishiyatsushiro Group, which extends around the Misaka Mountains. The geology of this area is part of the Southern Fossa Magna and is deeply involved in the formation of the Japanese archipelago.
In this study, we created a high-precision Red Relief Map of this area and analyzed its artificial topography. The accuracy of the Red Relief Map in this study is 25 cm and 50 cm mesh. In the Red Relief Map, the slope around the Nakayama gold mining ruins on Mt. Kenashi appears relatively smooth, even though this mountain is composed of tuff, which weathers easily. We found many flat terraces, traces of excavation, and artificially created lines on the slope, which are parallel to the contour lines. These artificially created lines seem to be scraped traces on the slopes of the mountain.
When the slope was artificially modified, it was shaped before the construction of terraces and structures at the Nakayama gold mining ruins, serving as their foundation. At Nakayama Gold Mine, pottery shards remaining on-site date back to the late 15th century, and it is believed that outcrop mining began in the early 16th century. If this is the case, the creation of this slope must have preceded the excavation of the tunnels, suggesting that the slope in the Nakayama Gold Mine area was formed in the early 16th century or earlier.
The current area designated as the Nakayama Gold Mining Ruins is approximately 16 hectares. However, the Red Relief Map reveals that artificial topographical modifications are not limited to the terraces but extend across the entire slope of Mt. Kenashi. The actual mining area is likely much larger, covering approximately 150 hectares, spanning about 3 km from east to west, 1.5 km from north to south, and ranging in elevation from 900 m to 1,850 m.
This research was carried out by the Science and Technology Public Relations Foundation, with support from the Watanabe Memorial Foundation for the Promotion of New Technology and a research grant for the first half of 2020.
In this study, we created a high-precision Red Relief Map of this area and analyzed its artificial topography. The accuracy of the Red Relief Map in this study is 25 cm and 50 cm mesh. In the Red Relief Map, the slope around the Nakayama gold mining ruins on Mt. Kenashi appears relatively smooth, even though this mountain is composed of tuff, which weathers easily. We found many flat terraces, traces of excavation, and artificially created lines on the slope, which are parallel to the contour lines. These artificially created lines seem to be scraped traces on the slopes of the mountain.
When the slope was artificially modified, it was shaped before the construction of terraces and structures at the Nakayama gold mining ruins, serving as their foundation. At Nakayama Gold Mine, pottery shards remaining on-site date back to the late 15th century, and it is believed that outcrop mining began in the early 16th century. If this is the case, the creation of this slope must have preceded the excavation of the tunnels, suggesting that the slope in the Nakayama Gold Mine area was formed in the early 16th century or earlier.
The current area designated as the Nakayama Gold Mining Ruins is approximately 16 hectares. However, the Red Relief Map reveals that artificial topographical modifications are not limited to the terraces but extend across the entire slope of Mt. Kenashi. The actual mining area is likely much larger, covering approximately 150 hectares, spanning about 3 km from east to west, 1.5 km from north to south, and ranging in elevation from 900 m to 1,850 m.
This research was carried out by the Science and Technology Public Relations Foundation, with support from the Watanabe Memorial Foundation for the Promotion of New Technology and a research grant for the first half of 2020.