Petroleum geochemistry at the dawn of the 21st century

Following a short review of the evolution of petroleum organic geochemistry in recent decades, this paper depicts the present status of research in the field and describes the guidelines dictated by the needs of the operators. Today, the industrial players are interested in increasingly deep prospects (high pressure, high temperature), in the exploration of the deep offshore, the search for gas and in the production of the planet's enormous heavy oil reserves. In this context, the challenge is to contribute effectively to the quantitative prediction of the oil and gas reserves at the scale of a basin (volume, composition, uncertainties) and to predict the quality of the fluids present in a reservoir, through a closer knowledge of the geochemical events affecting their preservation and their alteration.