DI Peng-fei1,3, WANG Jin-rong1, ZHANG Qi2, YANG Jing1, CHEN Wan-feng1, PAN Zhen-jie1, Du Xue-liang1, JIAO Shou-tao2,4
1. School of Earth Sciences, Lanzhou University;Key Laboratory of Mineral Resources in Western China, Lanzhou 730000, China;
2. Institute of Geology and Geophysics, Chinese Academy of Sciences, State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China;
3. Gansu Assessment Center of Mineral Resources Reserves, Lanzhou 730000, China;
4. Beijing Institute of Geology and Mineral Resources, Beijing 100012, China
Abstract：Basalt is a kind of basic rocks widely occurring in oceans the continents. Its genetic theory is mainly based on researches of large igneous provinces, however tectonic environment discrimination is mainly on the plate tectonics theory. With the development of plate tectonic theory, tectonic discrimination of basalts should be reconsidered. In this study, we investigate the reliability of current discrimination diagrams with GEOROC and PetDB database of global mid-ocean ridge basalt (MORB), ocean island basalt (OIB)and island arc basalt (IAB). Some discrimination diagrams were based on typical cases without including most of new published data so that they can not distinguish the types of basalts well. Although earlier discrimination diagrams have been widely applied, diagrams in terms of all data of basalts would be more reliable for discrimination. Thus, we improved these diagrams with all data. On the new diagrams, we found that IAB can be distinguished well from MORB and OIB. MORB and OIB are still mostly overlapped, indicating that MORB and OIB source components are possible to share a certain similarity. So, new diagrams based on big data can significantly promote the research of basalt tectonic environment discrimination.
Key words：big data basalt tectonic discrimination diagrams MORB OIB IAB
Bulletin of Mineralogy, Petrology and Geochemistry Vol.36, No.6, 2017, page 891-896