Integrating 60 years of paleontological research: A new geologic map of the Madygen Geopark, Kyrgyzstan

The southwestern margin of the Central Asian Fergana Basin is a tectonically complex region with a 500 million year record of sedimentation. Cambrian to Middle Carboniferous passive margin and carbonatic shelf sediments were intensively deformed by the closure of the Turkestan Ocean in the Late Carboniferous. After a period of uplift and erosion, a sucession of small Triassic-Jurassic nonmarine basins with a highly diverse and globally significant fossil record formed. Following repeated marine incursions in the Upper Cretaceous, the Fergana Gulf connected the eastern Peri-Tethys, Tethys, and Siberian epicontinental sea during major phases of global climate change in the Paleogene. Repeated convergence and uplift in the Neogene and Quaternary formed todays’ topography. Soviet 1:200,000 scale mapping in the 1950's was predicated on geosynclinal theory and failed to recognize the nappe architecture of the South Fergana Zone, leading to inaccurate ideas on basin configuration and paleoenvironmental reconstructions. Building on a field mapping campaign in 2007-2009, the core area of the Madygen Geopark is being remapped at a 1:25,000 scale by a combination of field work, remote sensing and geomorphological analysis. Together with newly logged profiles of the most important fossiliferous sucessions, the paleogeographic and paleoenvironmental history of the Madygen geopark is being reassessed.

The results will enable the reinterpretation of the voluminous fossil collections of the past six decades of paleontological research in terms of paleoecology, depositional environment and possible migratory pathways. Finally, the new geologic map will facillitate further research, educational and geotouristic activities at the Madygen Geopark.