Stratigraphic correlations of European platform in the frame of Peri-Thetys Programme (General Introduction)

It is now possible to synthesize the available data from the basins and their associated petroleum systems which border (or are included in) the Tethyan chains because: 1. Numerous geologists have recently undertaken doctoral thesis in regions around Tethys and numerous synthetic works have been realized by different teams. Often, only the concepts have been published and the data on which these conclusions are based are not easily available. 2. Many data derived from industry are legally available in general ten years after their acquisition. Some of these data have been published in a Mémoire du Muséum national d'Histoire naturelle (Peri-Tethys Memoir n° 2, tome 170, 1996). 3.The countries which previously had planned économies have begun to be more opened to market forces and those data are becoming more accessible and can now be synthesized with those of other countries. This situation allows the synthesis of basins in terms of their petroleum systems. This necessitates: 1. The creation of teams which have at their fingertips the data which were not available formerly. 2. To determine a chronological scale and a common vocabulary between the different cultures. At the present time, the problem of stratigraphical correlations is the critical aspect for all attempts which try to synthesize the three types of data mentioned above. The work purpose is to examine the behaviour of Peri-Tethyan sedimentary basins in the light of the framework provided by the end of the Variscan Orogeny, the opening of the Tethys and finally its closure between Eurasia and the Arabian-African plates. The region covered by the Peri-Tethys Programme has been limited in the north, in Europe, to the region between the Atlantic Ocean and the Urals and in the south, in Africa Arabia-Middle East as far as Indian Ocean. The present work is dealing only with the basins to the north of the Tethys. The final results will be presented in an atlas of twenty-two palaeogeographical maps with their legend. These maps will include palaeoenvironmental interpretations. Synchronism of objects will be examined as far as possible. The initiative for this Programme derives from Western Europe: the Tethys Programne (1989-1993) led to a synthesis of the Tethyan Ocean from the margins of Central America via the Alpine chains and the Himalayas to the Philippines during 250 million years (end Permian to Tortonian). During the Programme several European geologists have been added to the initial core which was dominated by the French. The Peri-Tethys Programme has added many teams working in such countries as Italy, the Netherlands, Germany, Switzerland, Belgium... This group has contacted geologists in other countries where there were relevant studies. Now that scientific exchange is easier between Eastern and Western workers the solutions to many stratigraphic problems may be found through joint projects and enable researchers to compile a more complete fossil record and allow interested workers to develop models that will facilitate more accurate interpretations of geological basins. The goal is to make biostratigraphical basin analyses a more useful tool both for industry and for academics. Taxonomic and stratigraphic syntheses are published from Tethyan regions but often no correlation is possible with geographical areas which were under Boreal influence. This gap in our knowledge results from different palaeogeographic domains (Boreal vs. Tethyan) and the fact that much of the Boreal data was acquired in eastern countries where methods and technical means were different