1∶50 000 Geological Map Database of Beiliutumiao Map-sheet, Inner Mongolia

According to the ‘Technical Requirement for Regional Geological Survey (1∶50 000)’ (DD 2019–01) and other uniform standards and requirements, and making full use of the data for 1∶200 000 regional geological and 1∶50 000 mineral survey, the 1∶50 000 Geological Map of Beiliutumiao Map-sheet (K49E011021), Inner Mongolia was compiled by adopting the Digital Geological Survey System (DGSS) in combination with Spot, ETM, Aster and other remote sensing images to continuously verify and modify tectonic and lithologic boundaries. As an achievement with important value of reference in the Wenduermiao-Bainaimiao area of Inner Mongolia, the map provides detailed information on the rock composition and tectonic association of the Bainaimiao island-arc belt. We re-divide sedimentary formation into different types, i.e., Silurian, Permian, Cretaceous, and classify intrusive rocks in the region into four phases, establishing a relatively complete tectonic evolutionary series. The map database includes three informal mapping units, 10 formal stratigraphic units, four periods of magmatic events and two tectonic deformations, as well as the whole rock analysis of 176 samples, and zircon U–Pb ages of 10 samples, with a data size of 28.9 MB. The map details the tectonic and magmatic evolution process of the Bainaimiao subduction belt formed in the southward subduction of the Wenduermiao tectonic belt in the north. Reflecting the latest results of the 1∶50 000 regional geological survey, the database holds important scientific value regarding the Paleozoic tectonic evolution of the Wenduermiao orogenic belt. It may also serve as an important reference for subsequent geological surveys in the region. As the first pilot map of China Geological Survey to apply comprehensive regional geological survey mapping, the present project represents the first time to realize whole-process field investigation in China’s regional geological surveys.