Earth Science Frontiers ›› 2012, Vol. 19 ›› Issue (3): 101-112.

• Article • Previous Articles     Next Articles

Nanogeochemistry: Deeppenetrating geochemical exploration through cover.

  

  1. Institute of Geophysical and Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China
  • Received:2012-02-20 Revised:2012-04-30 Online:2012-05-25 Published:2012-05-25

Abstract:

Deeppenetrating geochemistry have revealed that anomalies do exist at surface overlying mineral deposits covered by transported overburden. We do not yet fully understand the dispersion processes though many researchers recently have given different migration models. Nanoparticles of metals were observed in gases, soils and ore rocks at the coppernickel and gold deposits using a transmission electron microscope (TEM) equipped with an energy dispersive spectroscope. Particle diameters range from 10 to 200 nm. Most of them are generally tens of nanometers in diameters with ordered crystal structure observed by the TEM. The particles tend to assemblage shaped like a grape cluster. The particles are composed of native copper, compound metals of CuFe, CuFeMn, CuAg, CuCr, CuNi, and compound metals with Si, Al, Ca, O, P from the coppernickel deposit and Au, CuAu, CuFe, CuTi from the gold deposit. The facts show that nanoscale particles both in gases and soils are from the same source and the nanoscale particles with ordered crystal structures further indicate that they originated from the concealed CuNi deposit. The migration model can be interpreted as that nanoscale particles of metals from the ore body are adsorbed onto surface of gas bubbles and migrated with an ascending flow of gases upward to the surface, arriving at the surface, part of particles are persisting in the soil gases and the other part of particles are trapped by soil geochemical barriers. The findings of nanoscale particles of mineralization metals provide direct observation evidence for migration mechanism of deeppenetrating geochemistry and a new method for separation of nanoscale particles from soils to search for concealed deposits.

Key words: transported cover, concealed deposit, nanoscale metal particles, penetrating geochemistry, migration mechanism

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