Search

The tidal notch and the sea caves which cut into the Namigata Limestone is stiuated in 240m above sea level, Ibara City. The notch assocciates the Namigata Terrace 200m to 240m high. These geomorphological features indicate an event of high sea level. However the age of the event has not been known.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who used the cave sites were influenced by the sea level changes or other enviroumental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planed the excavation of the cave sites, and carried out the research at Sarugahana Todai cave site, Mihonoseki town, Shimane prefecture, in 1995, 1996 and 1997 (Takehiro and Watanabe et al., 1996 ; Takehiro and Ege et al., 1997 ; Takehiro and Watanabe et al., 1998). In 1998, we carried out the 2nd excavation of Sarugahana Todai cave site and the trial excavation of Location rock shelter, 15 m west of the cave site. In the 2nd excavation of this cave site, we excavated about 2.5 m^2 range in the front of the cave site, and reached about 0.9 m above the sea level. As one of the result of this excavation, we could find occupied surface around 1.2-1 m above the sea level, which is thought to belong to the later part of the early stage of the Jomon period or the former part of the middle stage of it, ca. 5,500 - 4,500 uncal. y. B .P.. And these date of occupation at this cave site are one of the oldest example of occupation in the cave sites at Shimane Peninsula at present. We could get the important data to research the problem about the date of the Jomon marine transgression, and so on. In the trial excavation of Location rock shelter, we excavated about 2 m^2 range at the inner part of rock shelter. We found the occupied surface at 1 m depth below the present surface. And we found the archaeological remains of the Jomon and Yayoi periods.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planned the excavation of the cave sites, and carried out the excavation at Sarugahana Todai cave site, Mihonoseki Town, Shimane Prefecture, in 1995 and 1996 (Takehiro and Watanabe et al., 1996 ; Takehiro and Ege et al., 1997). In 1997, we researched the Location rock shelter, 10 m west of Sarugahana Todai cave site. In this location we found some archaeological remains, Jomon potsherd, obsidian flakes and so on, in 1996's research. This location was probably thought to be the archaeological site, and we carried out a preliminary survey at this location. Judging by the present data, the rock shelter at this location is thought to be formed by the ancient marine erosion, and to be used for the dwelling or other purposes. And this rock shelter is thought to have suffered the marine erosion or other influences continuously after the emergence of the initial shape, so there is also the possibility that the initial shape of this rock shelter was the different form, for example, sea cave and so on. To study f'urther the significance of this location, we need to do more future researches.

There are many caves along Shimane Peninsula coast, and they are considered sea caves. Some of them were used by the ancient people for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient people who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we planed the excavation of the cave sites, and carried out the trial excavation at Sarugahana Todai cave site, Mihonoseki town, Yatuka gun, Shimane Prefecture, in 1995. In 1996, we carried out the first excavation at Sarugahana Todai cave site. This cave site is located facing the coastal line between Lake Nakaumi and Sakai Channel. The cave is opened about 4 m above the sea level at present, but the initial bottom of the cave is still unknown, because it is covered with the sediments which have been formed after the emergence of the initial cave. In this 1996s' excavation, we excavated about 10m^2 range of the cave site, and reached about 65cm above the sea level at the deepest excavated point, and we did not reach the initial bottom of the cave yet. As one of the result of this excavation, we could find the surface which is thought to be occupied at a certain time of the Jomon period(possibly the late stage of it), and its level is around 2.4m above the sea level at the south end of the trench. And we think there are more occupied surfaces under this surface. To study further this site and the other cave sites at Shimane Peninsula, we have to carry out more researches.

There are many caves along Shimane Peninsula coast, and they are considered the sea caves. Some of them were used by the ancient People for dwellings or other purposes, and remain as the archaeological sites. These cave sites are located facing the coastal line, so it is considered that the ancient People who would use or used the cave sites were influenced by the sea level changes or other environmental changes. And for these reasons, researches of the cave sites contribute to not only archaeological studies but also palaeo-environmental studies and so on. With these aims, we carried out a trial excavation at Sarugahana Todai cave site, Mihonoseki town, Yatuka gun, Shimane prefecture, and found archaeological materials of the Jomon period.