Geochemical Characteristics of the Bahuang Uranium Deposit in the Eastern Guizhou and Their Constraints on the Sedimentary Environment of the Phosphorite
HUANG Kai-ping, ZHENG Mao-rong, SUN Ping-ming, CHEN Fang
The 7th Team of the Non-ferrous Metals and Nuclear Industry Geological Exploration Bureau of Guizhou, Guiyang 550005, China
Abstract：In order to reveal the genesis of the phosphorite-type uranium deposit, a geochemical study on the phosphorite hosted in the bottom part of the Jiumenchong Formation in the Bahuang uranium deposit in Eastern Guizhou has been conducted in this paper. The results show that the phosphorite is characterized with the enrichment of U, V, REE, Sr and Sb. The chondrite-normalized REE patterns of the phosphorite are featured with LREE enrichment right-inclined patterns with medium to weak negative Ce anomalies (δCe=0.30~0.81) and medium negative Eu anomalies (δEu=0.61~0.71).The low Th/U ratios (0~0.04) and highδU values (1.97~2.00) of the phosphorite indicate that it was formed in the anoxic reduction environment. The ratios of Fe/Ti, (Fe+Mn)/Ti and Al/(Al+Fe+Mn) of the phosphorite, varying from 54.24 to 121.5, from 55.35 to 123.7, and from 0.34 to 0.47, respectively, show both characteristics of the normal marine sedimentation and the submarine hydrothermal deposition. The high U/Th ratios (25.42~374.50) indicate that the source of U was probably associated with the submarine Sedex type hydrothermal activity. Therefore, It can be considered that the genesis of the Bahuang uranium deposit in Eastern Guizhou was related to the intermittent submarine Sedex type hydrothermal activity.
黄凯平, 郑懋荣, 孙平明, 陈芳. 黔东坝黄铀矿床地球化学特征及其对磷块岩沉积环境的制约[J]. 矿物岩石地球化学通报, 2018, 37(2): 334-343.
HUANG Kai-ping, ZHENG Mao-rong, SUN Ping-ming, CHEN Fang. Geochemical Characteristics of the Bahuang Uranium Deposit in the Eastern Guizhou and Their Constraints on the Sedimentary Environment of the Phosphorite. Acta Metallurgica Sinica, 2018, 37(2): 334-343.
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