Acta Geologica Sinica (English Edition), 2019, 93(supp.l): 76-79 Deep-time Paleogeographic Reconstruction Based on Database: Taking the South China T. approximatus Biozone (Early Ordovician) as an Example ZHANG Linna1, ., FAN Junxuarr' and CHEN Qing' (I GSC 1 State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy ofSciences, Nanjing 210008, China 2 School ofEarth Sciences and Engineering, Nanjing University, Nanjing 210023, China 3 CAS Key Laboratory ofEconomic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy ofSciences, Nanjing 210008, China Citation: Zhang et al, 2019. Deep-time Paleogeographic Reconstruction Based on Database: Taking South China of the T. approximatus Biozone (Early Ordovician) as an Example. Acta Geologica Sinica (English Edition), 93(supp. 1): 76-79 Paleogeography is a discipline that studies spatial distribution and evolutionary characteristics of geographic objects in earth history (Feng, 2003; Feng et al., 2012). It focuses on the sediments, organisms and environmental proxies, most of which are preserved in the rocks. However, a large amount of this geological and biological information was no longer preserved after the geological process of burial, preservation and transformation. This loss caused great difficulties in producing paleogeographic reconstructions of high temporal precision and spatial resolution. With as much geological data as possible, and by using quantitative methods, the influence of incompleteness in geological records can be reduced. Here, we discuss the concepts and methods of paleogeographic reconstruction in the context of rapid developments in geochronology, geological big data and geographic information systems (GIS). We illustrate these procedures on data from the Early Ordovician Tetragraptusapproximatus Biozone of South China, creating the paleogeographic maps and analyzing their geological significance. 1 Concepts and methods in deep-time paleogeography High temporalprecision Precise time frameworks provide the basis to understand the details of regional and global paleogeographic evolution. Through the rapid development of the various subdisciplines of stratigraphy and geochronology (e.g., biostratigraphy and biochronology, cyclostratigraphy, astrochronology, magnetic stratigraphy, geomagnetic polarity studies, isotope stratigraphy, geochronology, statistical and quantitative stratigraphy, geochronology; Gradstein et al., 2012), the assessment of geological time can be improved, with 'deep time' becoming one of the most important concepts in geology (Sun and Wang, 2009; Wu, 2011). At present, 72 GSSPs, nearly 69.9% of the total GSSPs, have been designated (Fan et al., 2018). Thus, most geological stages have been established. In addition, precise refinements of the geologic timescale (to biozone level) was published for regions, such as South China, North America, Australia and Europe. * Corresponding author. E-mail: Inzhang@nigpas.ac.cn High spatial resolution Higher spatial resolutions and larger-scale paleogeographic maps can be used to pinpoint paleogeographic locations, boundaries, units and even evolutionary patterns of facies more accurately, which enhances the power of paleogeography. However, with the rapid accumulation of geological data, issues such as integration, management, sorting, verification and use of such huge amounts of geological information becomes a significant and inevitable problem. Digital databases represent an important way to resolve this problem (e.g., PBDB and GBDB; Fan et al., 2013, 2016). Through the assembly of digital databases with appropriate data structures (Table 1), users can store, organize, and use geological data more efficiently. Meanwhile, if all data are digitized and stored based on uniform standards, data entry, retrieval and update can be accomplished in an accurate and convenient manner. Ideally, all geological data need to be FAIR, i.e., Findable, Accessible, Interoperable, and Reusable. From qualitative to quantitative The pathway from qualitative to quantitative is an important indicator of the state of a discipline's development. In terms of paleogeography, quantification brings at least two important advantages. First, quantitative paleogeography can make use of use numerical or digitized maps to express the distribution pattern of paleogeographic units more accurately. Second, since the data for paleogeographic research come mostly from rocks and fossils, it is difficult to avoid the influence of incompleteness of rock and fossil records. Quantitative paleogeography can help eliminate this kind of influence through mathematical data analysis and statistics, so as to reveal the actual state of observations as well as assisting with inferences and interpretations. For example, paleobiogeography usually represents the geographic distribution of a species by enclosing the set of localities where the fossils are found within a boundary. Inevitably this represents an underestimate of the true geographic range because of the incompleteness of fossil records. However, by using the known fossil occurrences and environmental data, a quantitative paleogeographic methods and can be used to construct a mathematical species distribution models (SDMs), that can then be applied to an entire study area © 2019 Geological Society of China http://www.geojournals.cn/dzxbcn/ch/index.aspx https://onlinelibrary.wiley.com/journal/17556724