The Element XR was used to analyze the geochemical characteristics of elements in the anthraxolite. The results show that the element abundance of anthraxolite is apparently different from that in shale and surrounding rock. Furthermore, V(1039.40 μg/g), Ni(345.90 μg/g), Sr(227.67 μg/g) and Mo(64.70 μg/g) have significant enrichment. Analysis of the occurrence and enrichment pattern of the four elements shows that the enrichment of V and Ni in anthraxolite is the comprehensive effect of three aspects, including the trace element characteristics in crude oil, strong chelation and evolution of crude oil. With the absolute content of the element not reduced or even incremental, the loss of other elements and organic matter extrudes the relative enrichment of V and Ni to some extent. Mo shares the similar occurrence and enrichment mechanisms with V and Ni. The concentration of Sr may be related to the dissolution of Sr in the stratum during the migration process of crude oil, and the organic complexation in the heat evolution process of oil in the reservoir, but it may also be related to the unclear geochemical behavior of the element Sr.

Xiangxi  /  anthraxolite  /  trace elements