High-resolution annotated dataset of Girvanella boundstone microfacies from the Xiannüdong Formation, China

This dataset contains high-resolution image tiles and annotations derived from thin-section slabs of calcimicrobial crust–cement boundstones from the Xiannüdong Formation (Cambrian Series 2), South China.The dataset consists of two main components:(1) PNG image tiles (114 × 114 pixels) extracted from thin-section slab images, organized into training, validation, and test subsets.(2) A CSV file providing class labels and metadata for each image tile, including relative file paths and dataset splits.The data were generated using a point-counting-based automated annotation workflow and are intended for use in deep learning and machine learning applications focused on carbonate microfacies classification. The dataset is designed to support reproducible research and adheres to FAIR data principles.