Effect of temperature on mudstone disintegration process revealed with image analysis

Abstract

Quantifying rock weathering processes, especially in ways of nondisturbance and on-site investigation, is one of the most critical tasks in predicting rocks erosion rates and understanding the sediment transportation. We proposed a more reproducible approach to test how image analysis can quantify the changes in the size and shape of fragments during the weathering process. Four artificial models were designed to select suitable metrics among over 20 parameters. To validate the efficiency of image analysis, we analyzed rocks from badlands in Nanxiong Basin, Southeast China, under three different ranges of temperature differences (TD) during cyclic wetting and drying (WD). Our results show that TDs can accelerate the disintegration rate, and even if there is only a 20°C difference in the range of TDs, an apparent difference in fragment size was observed. Moreover, the shape of fragments became more round as the increasing number of cyclic treatments, and for samples that went through the same number of treatments, the larger the temperature difference, the more round the shape became. All that serves as another evidence for landscape evolution response to climatic warming.