Organic-mineral interfacial chemistry drives heterogeneous nucleation of Sr-rich (Ba x , Sr1-x )SO4 from undersaturated solution.

ABSTRACT: Sr-bearing marine barite [(Ba x , Sr1-x )SO4] cycling has been widely used to reconstruct geochemical evolutions of paleoenvironments. However, an understanding of barite precipitation in the ocean, which is globally undersaturated with respect to barite, is missing. Moreover, the reason for the occurrence of higher Sr content in marine barites than expected for classical crystal growth processes remains unknown. Field data analyses suggested that organic molecules may regulate the formation and composition of marine barites; however, the specific organic-mineral interactions are unclear. Using in situ grazing incidence small-angle X-ray scattering (GISAXS), size and total volume evolutions of barite precipitates on organic films were characterized. The results show that barite forms on or

SUBMITTER: Deng N 

PROVIDER: S-EPMC6612914 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature