This work aims discussing the contribution of environmental and technological factors in rock art painting preservation, based on a 3-year experimental program and two archaeological cases from Patagonia (South America). Concerning technological factors, microscopic information of experimental and archaeological contexts indicate that fine-grained pigments have a better preservation potential than coarse-grained ones, likely related to the high binder adsorption capacity of silty and clay size particles, resulting in a strong pigment agglutination and substrate adherence. Mechanical entrapment/translocation of such small particles into the substrate further contributes to preservation. The experiment also evidences that blood-bearing paints present preservation advantages over fat/water-based ones, probably due to clotting and drying processes which agglutinate pigments and seal rock voids, avoiding binder migration. In contrast, experimental gypsum- and, to a lesser extent, charcoal-based paints show a rapid and significant deterioration, particularly in the temperate and humid context. The low archaeological expectancy derived from these results is supported by the scarce and/or ambiguous regional representation of these black pigments in ancient Patagonian paintings. Among natural factors, water-related processes (i.e., rainfall, snow, freezing and water infiltration) play a decisive role in the physicochemical paint degradation, also favoring bioactivity. Raman spectroscopy of neoformed white crystals in experimental paints may evidence, in a short term, a first stage of the profuse biomineralizations archaeologically observed, associated with lichens, fungus, and endolithic organisms. Finally, sheep rubbing and wind abrasion are proposed as the main agents affecting vertical frequencies and integrity of archaeological motifs at the cave and open-air contexts, respectively, whereas differences related to cardinal insolation likely impact in frequencies, motif color and weathering stages at the open-air site too.

本作品旨在基于为期三年的实验计划和巴塔哥尼亚（南美洲）的两个考古案例，讨论环境和技术因素对岩画保存的贡献。从技术因素来看，实验和考古的微观信息表明，细粒颜料比粗粒颜料具有更好的保存潜力，这可能与粉质和粘土尺寸颗粒的粘结剂吸附能力强，导致颜料强烈凝集和沉积有关。基材附着力。将此类小颗粒机械截留/移位到基材中进一步有助于保存。该实验还证明，与脂肪/水基涂料相比，含血涂料具有保存优势，这可能是由于凝结和干燥过程使颜料凝集并密封岩石空隙，避免粘合剂迁移。相比之下，实验石膏基涂料和木炭基涂料（在较小程度上）显示出快速且显着的劣化，特别是在温带和潮湿的环境中。这些结果得出的考古预期较低，这一点得到了古代巴塔哥尼亚绘画中这些黑色颜料稀缺和/或模糊的区域代表性的支持。在自然因素中，与水相关的过程（即降雨、降雪、冰冻和水渗透）在油漆的物理化学降解中起着决定性作用，也有利于生物活性。实验涂料中新形成的白色晶体的拉曼光谱可能在短期内证明考古学观察到的与地衣、真菌和内石生物相关的大量生物矿化的第一阶段。最后，羊摩擦和风磨损被认为是分别影响洞穴和露天环境中考古图案的垂直频率和完整性的主要因素，而与基本日照相关的差异可能会影响洞穴中的频率、图案颜色和风化阶段。露天场地也是如此。