Photomicrograph dataset of rocks for petrology teaching in Nanjing University

Thin sections have always played an irreplaceable role in the nearly 100-year history of petrology teaching and research in the School of Earth Sciences and Engineering, Nanjing University. Though these thin sections for teaching have gone through the process of depletion, loss, adding, and renewal, they include 28 different kinds of sedimentary rocks, 40 kinds of igneous rocks, and 42 kinds of metamorphic rocks. These thin sections in Nanjing University cover over 90% of the common types of rocks, including more than 95% of the common minerals and rock textures required by the syllabus of geology major. This dataset electronically informatizes the thin sections currently used by Nanjing University for petrology teaching here. A total of 2658 polarized-light micrographs from 330 thin sections of 110 different kinds of rocks have been completed. In order to better share the teaching materials of petrology, the photomicrographs and information tables of these thin sections are shared with peers. Teachers can use them for teaching, or students can do some professional training and self-study through the dataset. In addition, these high-quality image data with uniform standards can be used for cross-researches such as machine learning and automatic identification of rocks. These photomicrographs can also be used as materials for advertising and pattern design in production practice.