8.3.1. Lithic raw material use in the vicinity of the Chivay source

Within the larger survey area, the radial attenuation pattern of obsidian artifacts around the Chivay obsidian source is a common characteristic of single-point raw material sources. This attenuation resembles a distance-decay pattern, but on a local scale. Obsidian artifacts dominate the assemblages in Survey Blocks 1, 4, and 5; the ones that are adjacent to Chivay source, while locally available chert and quartzite are well-represented in assemblages in Block 3, the upper Colca river valley. The impetus for quarrying in the Maymeja area appears to have been driven by a demand for larger obsidian nodules, and for obsidian material with few heterogeneities. Complete artifacts with > 30% cortex, including tools, flakes, and cores, were considerably larger in Block 1 than in other blocks. In surface assemblages in Block 2, which lies the same distance from the Chivay source as Block 3, obsidian dominates the lithic artifacts and andesite and other fine-grained volcanics are also present. On the surface of Blocks 1, 4, and 5, close to the Chivay source, obsidian cores and cortical flakes are more common, and in Blocks 1 and 5 bifacial thinning flakes (BTF) were relatively common with the highest fraction of BTF being located at the site of A03-910 in Block 5.