Baiguzina Almira Zyabirovna RussiaSaratovSaratov State University, 83, Astrakhanskaya Str., Saratov, 410012, Russiapost-graduate studentGoncharenkoOP@mail.ru Author's articles Peculiarities of Compositions and Formation Environments of Potassium and Potassium-Magnesium Rocks From the Pogozhskaya Rhythmic Member in The Northwestern and the Northeastern Parts of the Caspian Slope Zone