The Study Of Marine Source Rock Hydrocarbon-generating Kinetics

West Africa Passive margin basins is currently a hot area for exploration in the world due to the abundance of petroleum.Organic petrology was used in combination with hydrocarbon generation kinetics to unravel the correlation between organic facies and kinetic characteristics of source rocks in the Niger Delta and the Lower-Congo Basin.Different types of marine source rocks were investigated with Rock-Eval and hydrous closed system pyrolysis to reveal the hydrocarbon generation mechanism.The organic facies distribution characteristics have plenty of practical applications in the petroleum exploration field.Organic facies of passive margin basins West Africa were classified based on the characteristics of organic geochemistry,sedimentary environments and macerals composition.In our study,the Madingo and Paloukou Formations in the Lower Congo Basin belong in Restricted Sea High Sapropelinite Organic Face.And the Akata and Agbada Formations in the Niger Delta sedimented in Prodelta/ Shallow Sea Exintie-Sapropelinite Organic Face,Delta Front/ Shallow Sea Vitrinite-Exintie Organic Face and Inshore Swamp Vitrinite-Exintie Organic Face.Samples from two typical basins were conducted by Rock-Eval and hydrous confined system Pyrolysis.With Rock-Eval analysis,kinetic parameters were calculated,and it suggested that the source rocks in both areas contain low activation energy.The distribution of activation energy is homogenous and the hydrocarbon generation is fast which do favor of oil and gas accumulation.This study explored the main control factors of the West Africa passive margin basins development.A marine source rocks general formation model was established,based on the study of organic matter preservation,paleosedimentary environment and primary productivity.