広島県北部における弥生墳丘墓の成立と展開 : 佐田谷・佐田峠墳墓群の発掘調査を通して <考古学研究室の調査研究: 論文>

This paper discusses aspects of the emergence and development of Yayoi-period burial mounds, found in the San’in region, western Honshu, and the Chugoku mountain range area.

In 2008, the Archaeology Laboratory of the Hiroshima University Graduate School of Letters’ began a six-year excavation project at the Satadani-Satadao burial mound group near Shobara City in Hiroshima prefecture. One important result of this research was the discovery of variations in Yayoi burial mound construction techniques. Satadao burial mound No. 3, constructed at the end of the Middle Yayoi period, was built according to a technique, that may be termed “concurrent progressive,” wherein the mound was built by repeated iterations of grave digging, burials, and addition of soil. In contrast, Satadani burial mound No. 1, dating to the beginning of the Late Yayoi period, may be considered to use a style termed here “mound first,” wherein soil was first piled to form a mound, prior to excavation of the grave and burial.

Our research showed that from the San’in region to the Chugoku mountain range, a type of burial, termed here, the “mound last” type, is found, wherein an earth mound was constructed only after digging the grave and completing the burial. The “concurrent progressive” types referred to previously, were common in the Middle Yayoi phase.

The “mound-first” type noted at Satadani burial mound No. 1 appeared in the Late Yayoi period with attributes suggesting that it was the source for the remarkably large burial mounds of the final phase of the Late Yayoi period, such as those in the San’in region, southern Okayama prefecture, and the Tango peninsula. Thus, we identify the Satadani-Satadao burial mound group as an extremely important archaeological site for studying the development, in terms of appearance and increase in size, of the Yayoi-period burial mounds.