Organomineralization in Mesoproterozoic giant ooids》.pdf

Journal of Asian Earth Sciences 107 (2015) 195–211 Contents lists available at ScienceDirect Journal of Asian Earth Sciences journal homepage: www.else /locate/jseaes Organomineralization in Mesoproterozoic giant ooids Dongjie Tang a,b, Xiaoying Shi a,c,⇑, Qing Shi b, Jinjian Wu c, Gaoyuan Song c, Ganqing Jiang d a State Key Laboratory of Biological and Environmental Geology, China University of Geosciences, Beijing 100083, China b Institute of Earth Sciences, China University of Geosciences, Beijing 100083, China c School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China d Department of Geoscience, University of Nevada, Las Vegas, NV 89154-4010, USA a r t i c l e i n f o a b s t r a c t Article history: Ooids are common carbonate particles that are traditionally considered as abiogenically formed by phys- Received 8 January 2015 ical and chemical processes in highly agitated environments. Recent studies point to the importance of Received in revised form 11 March 2015 microbial activities in ooid formation, but more case studies are required to confirm and clarify the roles Accepted 20 April 2015 of microbes and their organomineralization processes. Here we report an integrated petrographic, ele- Available online 6 May 2015 ment geochemical, and isotopic study of Mesoproterozoic giant ooids from the Wumishan Formation (ca. 1.50–1.45 Ga) of North China. The Wumishan giant ooids (2.0