The optical studies of fossil organic matter in reflected light have made great progress in recent decades with the development of coal petrology, completed around the end of the 1970s by fluorescence examination. As they are complementary to the studies in transmitted light (palynology) and organic geochemistry developed for petroleum exploration purposes, they have become a much used tool in the recognition of sedimentary thermal transformations. For more than fifteen years within the Elf-Aquitaine Group, these studies have been applied in their various aspects to furnish a better geological understanding of basins during exploration. They have enabled us to define liquid and gas hydrocarbon domains which they differentiate and have also enabled a better characterization of sedimentary environments. Perhaps the most unexpected result of these studies has been to reconstruct the thermal history of the basins. Unforeseen but promising, when deduced from the thermicity of the sedimentary cover, the crust thermicity forms a determining link-element between the deep tectonics and the basin formation. Over the last ten years, the significance of this theme of research has been reinforced thanks to the impressive development of geodynamic studies following the general change in ideas brought about by plate tectonics. The present-day geothermal studies, conducted simultaneously in the oceanic and continental domains, have provided it with an argumentation and richer references.

Inhalt
One The Thermal Diagenesis of Organic Matter and the Methods of Paleogeothermal Analysis.- 1. The Thermal Diagenesis of Organic Matter.- 2. Methods and Means of Paleothermal Analysis.- 3. The Shallow Transmission of Deep Thermal Flows Examples of very conductive or non-conductive series.- Two The Study of Organic Matter in Reflected Light and Fluorescence.- 4. The Optical Analysis of Sedimentary Organic Matter in Reflected Light and Fluorescence.- 5. Attempts at Classification of Organic Matter.- 6. The Main Groups of Organic Matter.- 7. The Rank Evaluation of Dispersed Organic Matter.- 8. The Alterations of Coal.- 9. Organic Matter Transformation: Hydrocarbon Generation.- Three A Paleogeothermal Survey of a Sequence of Sedimentary Basins Through the Study of Organic Metamorphism in Boreholes.- 10. The Rhine Valley, Continental Tertiary Trough.- 11. The Congo Basin, Lower Cretaceous Trough, Forerunner of The South Atlantic Oceanic Opening.- 12. The Red Sea, Active Oceanic Rift.- 13. The Japanese Archipelago, Island Arc or Oceanic Convergent Zone.- 14 Upper Bavaria, Foreland of the Alpine Collision.- 15. The Rhenish Paleozoic Massifs, The Ardenne and the Rhenish Schistose Massif: Complex Orogens.- 16. The Mesozoic Aulacogen or Bramsche Massif.- 17. The Lacq Region, Thermal Cretaceous Dome in Front of the Pyrenean Range.- Four Mineral Diagenesis: Comparison with Organic Diagenesis.- 18. Rock Metamorphism: The Role of Temperature and the 'Basement Effect' Concept.- 19. Mineral Diagenesis or 'Premetamorphism'. Evolution of Clay Minerals.- 20. Case Histories of Basin Diagenetic Surveys Using Clay Minerals In Comparison With Organic Evolution.- General Outlines.- 21. Main Results.- Conclusion.- References.- Abstracts.- General Index.- Geographical Index.- Index ofAuthors.- Glossary of Specialized Terms.