Changes

==Example of loss of C₁₅₊ fraction==

==Example of loss of C₁₅₊ fraction==

[[file:oiloil-and-oilsource-rock-correlations_fig8-15.png|left|thumb|{{figure number|11}}. Copyright: Unocal.]]

[[file:oiloil-and-oilsource-rock-correlations_fig8-15.png|left|thumb|{{figure number|11}}gas chromatogram of saturated hydrocarbons in a source rock extract from which the extracting solvent was evaporated too vigorously, leading to loss of some of the C₁₅₊ fraction. Copyright: Unocal.]]

[[:file:oiloil-and-oilsource-rock-correlations_fig8-15.png|Figure 11]] shows a gas chromatogram of saturated hydrocarbons in a source rock extract from which the extracting solvent was evaporated too vigorously, leading to loss of some of the C₁₅₊ fraction. This problem can be recognized by looking at the ''n''-C₁₇ and ''n''-C₁₈ peaks. Normally they are almost the same size, but in this case the ''n''-C₁₇ peak is much smaller. Pristane has also been depleted relative to phytane, leading to an erroneous pristane–phytane ratio unless some correction is made.

[[:file:oiloil-and-oilsource-rock-correlations_fig8-15.png|Figure 11]] shows a gas chromatogram of saturated hydrocarbons in a source rock extract from which the extracting solvent was evaporated too vigorously, leading to loss of some of the C₁₅₊ fraction. This problem can be recognized by looking at the ''n''-C₁₇ and ''n''-C₁₈ peaks. Normally they are almost the same size, but in this case the ''n''-C₁₇ peak is much smaller. Pristane has also been depleted relative to phytane, leading to an erroneous pristane–phytane ratio unless some correction is made.