Salt deposits of the Ufimian Formation in the Solikamsk depression

Abstract

The paleogeographic and tectonic conditions of the accumulation of Ufimian deposits (Lower Permian) were reconstructed on the basis of study more than 2000 wells within the Solikamsk depression. The most complete cross-section of the salt-marl formation (9 large layers of rock salt and gypsum rock) was studied. On this basis, the modified scheme of stratification of the salt-marl layer was proposed. The stratum was dismembered, both with complete and partial preservation of the salt layers. The stratum is divided into 3 large cyclothemes in this scheme, the cyclothemes - into series of cyclites. Each cyclite has a complete cycle of the evaporate sedimentation. The maps were constructed for each salt layer. The maps show the configuration of the salt lagoon and the migration of its depocenter within the Solikamsk depression (Ufimian age). The study of the cross-section shows the vertical change of the composition. The salt-bearing rocks are replaced by carbonate rocks - it corresponds to a general transgression in the region. For upper layers of salt-marl strata the facial replacement of the salt by gypsum rocks has been revealed. The analysis of the configuration of the reconstructed lagoon at the geological time demonstrates its connection with the regional tectonic events and salt tectonics in the Kungur sediments.

Keywords

• предуральский прогиб
• соликамская впадина
• галогенез
• уфимские отложения
• соляно-мергельная толща
• стратификация
• цикличность
• каменная соль
• гипс
• the uralian foredeep
• the solikamsk basin
• halogenesis
• ufimian deposits
• salt-marl layer
• stratification
• cyclicity
• rock salt
• gypsum