| Popis: |
Sixteen trace elements (Al, As, Br, Cl, Co, Cr, Eu, Fe, La, Mn, Mo, Ni, Sb, Sc, V and W) were determined in 36 crude oils and condensates from New Zealand sedimentary basins, mostly from the Taranaki Basin. Concentrations of Al correlated strongly with “clay mineral” elements such as Cr, Fe, La, Mn, Mo and Sc. This indicated that most of the trace elements were bound in entrapped clay fractions. Although a Ni vs. V plot did not allow for effective discrimination of different oils and condensates because the number of Ni values (6) was so small, the abundances of both elements were extremely low and in the same range of values as Chinese non-marine oils. Principal components analysis of the data showed that two components (involving 15 elements) accounted for 66.9% of the variance of the system. A mutual plot of these two components indicated that the Maui-1 offshore oil and the Waiotapu and Kotuku seepage oils were separate from the main group of crudes from the Taranaki Basin. |
