1∶500 000 Geological Map Spatial Database of the Xiwuqi and Bainaimiao Areas in the Erlian– Dongwuqi Metallogenic Belt

The 1∶500 000 Geological Map Spatial Database of the Xiwuqi and Bainaimiao Areas in the Erlian-Dongwuqi Metallogenic Belt is developed as part of China Geological Survey’s project ‘Geological and Mineral Survey of the Xiwuqi and Bainaimiao Areas in the Erlian-Dongwuqi Metallogenic Belt’ during 2016 to 2018. The stratum of the Paleozoic, Mesozoic, Paleogene and Neogene are divided into different formations, while the intrusive rocks are expressed in the form of ‘lithology + era’ based on 777 LA-ICPMS and SHRIMP zircon U–Pb ages. The geological map spatial database is rich in geological information with a data size of 210 MB, including 4682 stratigraphic and 1938 intrusive rock surface entities, all of which are associated with their corresponding attributes. The following achievements have been made during the mapping process: the Paleozoic stratigraphic division has been revised considering biota and key tectonic boundaries, with newly established and re-defined important stratigraphic units and an improved Paleozoic stratigraphic framework; the temporal-spatial distribution and properties of Paleozoic intrusive rocks have been clarified, with the Early and Late Paleozoic two-stage magmatism being responses to corresponding subduction-accretion orogeny; newly identified ophiolitic mélanges, such as Early Paleozoic Sayin Aobao, Changtu and Late Paleozoic Erdaojing-Diyanmiao and Wulangou, have been expressed on the map, which shows the structure of the accretionary orogeny formed by the Early Paleozoic North and South bi-direction subduction. The final closure of the Paleo Asian ocean at the end of the Late Paleozoic was constrained and the tectonic units were re-divided. These achievements and data may shed light on scientific issues with diverging views regarding the Xing’an–Mongolian orogeny, such as the division of the Paleozoic tectonic units and late Paleozoic tectonic setting. As the latest and most complete 1∶500 000 geological map database in the middle part of the Xing’an –Mongolian orogeny so far, this spatial database reflects the latest achievements of geological surveys and research in this area

二连-东乌旗成矿带西乌旗（Xiwuqi）与白乃庙（Bainaimiao）地区1∶50万地质图空间数据库，是中国地质调查局2016—2018年实施的“二连-东乌旗成矿带西乌旗、白乃庙地区地质矿产调查”项目的成果之一。本次数据库涉及古生界、中生界、古近系及新近系，均按不同组级地层单元划分；侵入岩则以“岩性+时代”的形式进行表征，其厘定依据共计777件LA-ICPMS与SHRIMP锆石U-Pb定年数据。该地质图空间数据库数据量达210 MB，蕴含丰富地质信息，共包含4682个地层实体与1938个侵入岩地表实体，所有实体均配套有对应的属性信息。本次编图取得如下成果：结合生物化石组合与关键构造边界，对古生界地层划分方案进行了修订，新建并重新厘定了重要地层单元，完善了古生界地层格架；明确了古生代侵入岩的时空分布规律与岩石成因属性，指出早古生代与晚古生代两期岩浆作用分别对应相应的俯冲-增生造山过程；新识别出的蛇绿混杂岩（ophiolitic mélanges）包括早古生代赛音敖包（Sayin Aobao）、长图（Changtu）以及晚古生代二道井-地彦庙（Erdaojing-Diyanmiao）、五狼沟（Wulangou），已全部编绘入图，这些岩体直观展现了早古生代南北双向俯冲作用形成的增生造山带构造结构；限定了古亚洲洋于晚古生代末期最终闭合的时限，并重新划分了区域构造单元。本次成果与数据集可为兴安-蒙古造山带（Xing’an–Mongolian orogeny）中长期存在争议的科学问题提供新的研究思路，例如古生代构造单元划分以及晚古生代构造环境等议题。作为目前兴安-蒙古造山带中段现势性最强、资料最完整的1∶50万地质图空间数据库，该数据集完整呈现了该区域最新的地质调查与研究成果。