Microelements in petroleums of West Kazakhstan

Fe, Ni, Co, Zn, Sc, Sb, Hf and Hg content in petroleums and gas-condensates of 22 beds of West Kazakhstan is determined by neutron-activation. The average concentration of these microelements is minimum in petroleums obtained from layers adjacent to salt-bearing deposits of Upper Permian age and increases in persalt petroleums with a reduction and in subsalt petroleums - with increasing depth of occurrence and age of the holding reservoirs. Fe, Ni, Co, Sc and Sb content in petroleums subjected to catagenic transformations from subsalt deposits increases in proportion to the extent of their metamorphic change. Gas-condensates contain on average the same metal microimpurities, which indicates a fairly high volatility of organometallic complexes under conditions of retrograde evaporation of mineral resources. 5 references, 1 figure, 3 tables