Correlation of oils to each other and to their source rocks is an essential component in defining a basin's petroleum system. Oil–oil correlations seek to determine whether oils were generated and expelled from the same source facies. Oil–source rock correlations attempt to determine the specific source facies that gave rise to an oil. Correlation studies endeavor to establish the original genetic relationship of geologic samples rather than a mere matching of bulk properties or chemical compositions. Because the original composition of an oil can be changed by secondary processes (e.g. thermal maturation, migration, and reservoir alteration such as biodegradation, thermochemical sulfate reducation and phase separation), petroleums with very different bulk, molecular, and isotopic compositions still may be genetically related.

The final outcome of all mentioned by Dr. El Nady is definition of petroleum system or systems. Eventually, these very important biomarker and isotopic investigations will increase the effectiveness of exploration process and minimize the risk of dry wells.

oil-oil and oil-source correlation is a method used to trace oils to their source. Oil composition is specific to various oils due to the presence of components known as fingerprints. No two oil can have similar fingerprints and hence its usage in correlation studies.

okay thank you for this additions. furthermore additions the oil-oil and oil-source correlation are being interested if made by the using of   the biological marker parameters and carbon isotope compositions  of the crude oils and source rocks

This article may be of help

https://www.researchgate.net/publication/5931596_Gas_chromatographic_fingerprinting_of_crude_oil_from_Idu-Ekpeye_oil_spillage_site_in_Niger-delta_Nigeria

Article Gas chromatographic fingerprinting of crude oil from Idu-Ekp...

thank you all authors for these answers

would you Tell me 5 or 6 outcomes of oil-oil correlation via biomarkers????

They are important Chronostratigraphic markers.