US EPA

2675441 

Journal Article 

Migration mechanisms of gold nanoparticles explored in geogas of the Hetai ore district, southern China 

Cao, J 

2011 

No 

Geochemical Journal
ISSN: 0016-7002
EISSN: 1880-5973 

45 

6 

E9-E13 

WOS:000299191100014 

Several studies have shown that gas flows (namely "geogas") ascending from the Earth's interior can, while passing through conceleal orebodies, assimilate ore nanoparticles and carry them to the surface. The orebodies might be detected by measuring nanoparticle contents in soil gas or in the atmosphere. However, the mechanism by which geogas carries gold nanoparticles from orebodies to the surface is not well understood. To investigate these migration mechanisms, suspended particles from deep gas in the Hetai gold ore district in southern China were collected, gold nanoparticles artificially added, and the distribution of the gold nanoparticles studied using a transmission electron microscope. This study showed that gold nanoparticles migrate by 1) adsorption onto other particles suspended in the geogas, including needle, spherical and flower-like shaped iron-bearing particles, spherical aluminous particles, and calcite; and 2) in aggregated form. 

geogas; gold; concelead ores; gas migration; nanoparticles