The invention consist of a process and method of geochemical trace and ultra-trace elementsfingerprinting of crude oils (unmixed or commingled) and then allocating or unmixing of commingle crude oils derived from two or more sources that can be commingled from 2-7 producing zones in a subsurface well, from commingled oils from 2-7 wells in an oil field pipeline or commingled crude oils from several pipeline streams where pipelines merge. The methods involve geochemical allocation using trace and ultra-trace elemental abundance data and differs from organic molecular techniques or PMT well logging techniques that tend to be more costly. The geochemical fingerprinting technique can also be used to monitor wells for decline and downhole blockage or other problems during production operations. The fingerprinting also allows oil-oil and oil-source rock correlations that can be used to determine the country origin, oil field origin, or source rock origin of the crude oils for exploration, production, or national security reasons.