2013.05.12 The third excavation of the Hiroppara site group 2013 in Nagawa Town, Nagano Prefecture, Japan

The third excavation of the Hiroppara site group 2013 in Nagawa Town, Nagano Prefecture, Japan

The Center for Obsidian and Lithic Studies, Meiji University has conducted the third excavation at the Hiroppara site group from 27 April to 12 March, 2013.
The third excavation was done at the Hiroppara II site, and also geological boring survey at the Hiroppara I and II sites.
　Principal cultural layers at the Hiroppra II site is as follows;
1. Layers 2a and 2b: the Jomon industry represented by the Incipient Jomon pottery.
2. Layer 3: a lithic industry in the late part of the Late Upper Palaeolithic represented by blades with multifaceted striking platform and side scrapers.
3. Layer 4a: a lithic industry in the early part of the Late Upper Palaeolithic represented by various knife-shaped tools, trapezoids, notched scrapers and thick blades with single-faceted striking platform in association with the obsidian concentration 1 (and 3). The Aira-Tn volcanic glass were detected in the lower part of the layer 4a.
4. Layer 4b: an edge-ground stone axe, thin blades with single-faceted striking platform represent an early part of the Early Upper Palaeolithic, and these were associated with the obsidian concentration 2. The layers below the layer 5 are sterile layers.
Of particular interest is an edge-ground axe that has indicated a diagnostic tool of the early part of the Early Upper Palaeolithic (ca. 40,000-35,000 cal BP). This is the first discovery of the edge-ground axe in the obsidian source area in central highlands at altitude of 14,000 m.