Analytical potential of 3D data in the ballistic analyses of lithic projectiles

Abstract

The total entry area of a projectile to the impacted object is a key ballistic parameter of lithic projectiles. Together with the assumed or experimentally testified penetration depth, it forms the first reception of the wounding capability of an individual projectile point, i.e., of the permanent wounding cavity volume. Mathematical operations are used to calculate the entry area, for which the manually measured dimensions of the projectile form input data. Nevertheless, these methods reconstruct only the cross-sectional area at only one point of the longitudinal axis of the object. Here, we propose a method of using high-resolution 3D data for precise measurements of the real entry area of a projectile, even in the case of barbed projectiles whose barbs exceed the width of the projectile body, as well as in cases of projectiles with an asymmetric cross-section. The proposed method of using 3D models to read the numerically expressed values of ballistic parameters was used to analyse almost 400 lithic archery projectiles found in the eastern part of Central Europe, dating from the Late Eneolithic and Early Bronze Age, a culminating period for lithic archery projectiles in the archaeological record.