Abstract:Objectives: Honeycombs are great interests of scientific community and the public alike owing to their delicate morphology and controversial formation processes. The honeycombs in the Danxiashan Global Geopark of South China occur along the cliff faces of the aeolian sandstones, which belong to the Second (Jinshiyan) Member of the Late Cretaceous Danxia Formation. In this study, two sites were chosen to discuss the influences of salt weathering on formation mechanisms of these honeycombs.Methods: Field investigation, size measurement, sandstone sampling and observation under a microscope were performed to obtain lithology, grain composition and fabric, and honeycomb sizes. Moreover, the Voronoi polygons were completed by using ArcGIS 10.2 software to compare with honeycomb openings.Results: The results show that the development locations of the honeycombs are largely selective. The two studied sites are facing downwards the Jinjiang River, which is beneficial for moisture availability and maintenance in them because of the curvature of the rock faces. The bedrock is aeolian sandstones with largescale crossbeddings and well permeability. In addition, the openings of honeycombs are basically in accordance with the Voronoi diagrams.Conclusions: The relatively homogeneous thickbedded aeolian sandstones are the crucial bedrock lithology, and the Jinjiang River supplies essential moisture for the development of the honeycombs in the study area. It can be deduced that small pits in the cliffs might generate from a number of points suitable for salt weathering during the initial development stage, and then gradually expands laterally along the same intervals. Owing to the ongoing salt weathering, the inside back walls are possibly being weathered at higher rates than the side walls of the honeycombs. Then the honeycomb cells cross through laminations, resulting in enlargement and deepening of them. As a result, the honeycomb openings are in agreement with Voronoi polygons at least in part during the mature stage. Eventually, as the honeycomb cells deepen, the side walls become thin and unstable and might suffer sudden collapse owing to the influence of the gravity and wind.